Biochemistry, Genetics and Molecular Biology › Biophysics

Spectroscopy Techniques in Biomedical and Chemical Research

Works Count: 63584

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Description

This cluster of papers focuses on the application of Raman spectroscopy, infrared spectroscopy, and related techniques in biomedical research. The papers cover a wide range of topics including protein analysis, tissue diagnosis, glucose monitoring, cancer detection, and chemical imaging for biomedical purposes.

Keywords

Raman Spectroscopy; Infrared Spectroscopy; Biomedical Imaging; Protein Analysis; Chemical Imaging; Tissue Diagnosis; Coherent Anti-Stokes Raman Scattering Microscopy; Glucose Monitoring; Cancer Detection; Vibrational Spectroscopy

Raman spectroscopy of proteins: a review

2013-07-13

Anna Ryguła , Katarzyna Majzner , Katarzyna M. Marzec +3 more

In this work, 26 proteins of different structure, function and properties are investigated by Raman spectroscopy with 488, 532 and 1064 nm laser lines. The excitation lines were chosen in … In this work, 26 proteins of different structure, function and properties are investigated by Raman spectroscopy with 488, 532 and 1064 nm laser lines. The excitation lines were chosen in NIR and Vis range as the most common and to show the difference due to normal and resonance effect, sometimes accompanied by the fluorescence. The selected proteins were divided, according to the Structural Classification of Proteins, into four classes according to their secondary structure, i.e. α‐helical (α), β‐sheet (β), mixed structures (α/β, α + β, s) and others. For all compounds, FT‐Raman and two Vis spectra are presented along with the detailed band assignment. To the best of our knowledge, this is the first review showing the potential of Raman spectroscopy for the measurement and analysis of such a large collection of individual proteins. This work can serve as a comprehensive vibrational spectra library, based on our and previous Raman measurements. Copyright © 2013 John Wiley & Sons, Ltd.

Infrared spectroscopy of biomolecules

1996-07-01

John L. Howland

A MICROSPECTROPHOTOMETRIC METHOD FOR THE DETERMINATION OF CYTOCHROME OXIDASE

1951-04-01

S.J. Cooperstein , Arnold Lazarow

Near infrared spectroscopy

1999-03-01

Huw Owen-Reece , Martin Smith , Clare E. Elwell +1 more

A RAPID PHOTOELECTRIC METHOD FOR THE DETERMINATION OF GLUCOSE IN BLOOD AND URINE

1937-08-01

William S. Hoffman

Reference database of Raman spectra of biological molecules

2007-04-11

Joke De Gelder , Kris De Gussem , Peter Vandenabeele +1 more

Abstract Raman spectra of biological materials are very complex, because they consist of signals from all molecules present in cells. In order to obtain chemical information from these spectra, it … Abstract Raman spectra of biological materials are very complex, because they consist of signals from all molecules present in cells. In order to obtain chemical information from these spectra, it is necessary to know the Raman patterns of the possible components of a cell. In this paper, we present a collection of Raman spectra of biomolecules that can serve as references for the interpretation of Raman spectra of biological materials. We included the most important components present in a cell: (1) DNA and RNA bases (adenine, cytosine, guanine, thymine and uracil), (2) amino acids (glycine, L ‐alanine, L ‐valine, L ‐serine, L ‐glutamic acid, L ‐arginine, L ‐phenylalanine, L ‐tyrosine, L ‐tryptophan, L ‐histidine, L ‐proline), (3) fatty acids and fats (lauric acid, myristic acid, palmitic acid, stearic acid, 12‐methyltetradecanoic acid, 13‐methylmyristic acid, 14‐methylpentadecanoic acid, 14‐methylhexadecanoic acid, 15‐methylpalmitic acid, oleic acid, vaccenic acid, glycerol, triolein, trilinolein, trilinolenin), (4) saccharides (β‐ D ‐glucose, lactose, cellulose, D ‐(+)‐dextrose, D ‐(+)‐trehalose, amylose, amylopectine, D ‐(+)‐mannose, D ‐(+)‐fucose, D ‐(−)‐arabinose, D ‐(+)‐xylose, D ‐(−)‐fructose, D ‐(+)‐galactosamine, N ‐acetyl‐ D ‐glucosamine, chitin), (5) primary metabolites (citric acid, succinic acid, fumarate, malic acid, pyruvate, phosphoenolpyruvate, coenzyme A, acetyl coenzyme A, acetoacetate, D ‐fructose‐6‐phosphate) and (6) others (β‐carotene, ascorbic acid, riboflavin, glutathione). Examples of Raman spectra of bacteria and fungal spores are shown, together with band assignments to the reference products. Copyright © 2007 John Wiley & Sons, Ltd.

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Evaluating Clinical Accuracy of Systems for Self-Monitoring of Blood Glucose

1987-09-01

William L. Clarke , Daniel J. Cox , Linda Gonder‐Frederick +2 more

Although the scientific literature contains numerous reports of the statistical accuracy of systems for self-monitoring of blood glucose (SMBG), most of these studies determine accuracy in ways that may not … Although the scientific literature contains numerous reports of the statistical accuracy of systems for self-monitoring of blood glucose (SMBG), most of these studies determine accuracy in ways that may not be clinically useful. We have developed an error grid analysis (EGA), which describes the clinical accuracy of SMBG systems over the entire range of blood glucose values, taking into account 1) the absolute value of the system-generated glucose value, 2) the absolute value of the reference blood glucose value, 3) the relative difference between these two values, and 4) the clinical significance of this difference. The EGA of accuracy of five different reflectance meters (Eyetone, Dextrometer, Glucometer I, Glucometer II, Memory Glucometer II), a visually interpretable glucose reagent strip (Glucostix), and filter-paper spot glucose determinations is presented. In addition, reanalyses of a laboratory comparison of three reflectance meters (Accucheck II, Glucometer II, Glucoscan 9000) and of two previously published studies comparing the accuracy of five different reflectance meters with EGA is described. EGA provides the practitioner and the researcher with a clinically meaningful method for evaluating the accuracy of blood glucose values generated with various monitoring systems and for analyzing the clinical implications of previously published data.

Microbiological characterizations by FT-IR spectroscopy

1991-05-02

Dieter Naumann , Dieter Helm , Harald Labischinski

Vibrational spectra in the CH stretching region and the structure of the polymethylene chain

1978-01-01

Robert G. Snyder , Shaw Ling Hsu , S. Krimm

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Fourier Transform Infrared (FTIR) Spectroscopy of Biological Tissues

2008-02-01

Zanyar Movasaghi , Shazza Rehman , Ihtesham Ur Rehman

Abstract This article reviews some of the recent advances on FTIR spectroscopy in areas related to natural tissues and cell biology. It is the second review publication resulting from a … Abstract This article reviews some of the recent advances on FTIR spectroscopy in areas related to natural tissues and cell biology. It is the second review publication resulting from a detailed study on the applications of spectroscopic methods in biological studies and summarizes some of the most widely used peak frequencies and their assignments. The aim of these studies is to prepare a database of molecular fingerprints, which will help researchers in defining the chemical structure of the biological tissues introducing most of the important peaks present in the natural tissues. In spite of applying different methods, there seems to be a considerable similarity in defining the peaks of identical areas of the FTIR spectra. As a result, it is believed that preparing a unique collection of the frequencies encountered in FTIR spectroscopic studies can lead to significant improvements both in the quantity and quality of research and their outcomes. This article is the first review of its kind that provides a precise database on the most important FTIR characteristic peak frequencies for researchers aiming to analyze natural tissues by FTIR spectroscopy and will be of considerable assistance to those who are focusing on the analysis of cancerous tissues by FTIR spectroscopy.

Using Fourier transform IR spectroscopy to analyze biological materials

2014-07-03

Matthew J. Baker , Júlio Trevisan , Paul Bassan +7 more

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Nonionizing electromagnetic wave effects in biological materials and systems

1972-01-01

Curtis C. Johnson , A.W. Guy

Electromagnetic waves from the lower radio frequencies up through the optical spectrum can generate a myriad of effects and responses in biological specimens. Some of these effects can be harmful … Electromagnetic waves from the lower radio frequencies up through the optical spectrum can generate a myriad of effects and responses in biological specimens. Some of these effects can be harmful to man at high radiation intensities, producing burns, cataracts, chemical changes, etc. Biological effects have been reported at lower radiation intensities, but it is not now known if low-level effects are harmful. Even behavioral changes have been reported. Most of the effects are not harmful under controlled conditions, and can thereby be used for therapeutic purposes and to make useful diagnostic measurements. The problem of microwave penetration into the body with resultant internal power absorption is approached from both the theoretical and the experimental viewpoints. The results are discussed in terms of therapeutic warming of tissues and possible hazards caused by internal "hot spots." The absorption and scattering effects of light in biological tissues are reviewed. Molecular absorption peaks in the optical spectrum are useful for making molecular concentration measurements by spectroscopy. Much of the related work in the literature is summarized, some new results are presented, and several useful applications of wave energy and medical instruments are discussed.

In Vivo Confocal Raman Microspectroscopy of the Skin: Noninvasive Determination of Molecular Concentration Profiles

2001-03-01

Peter J. Caspers , Hajo A. Bruining , Gerwin J. Puppels +2 more

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Obtaining information about protein secondary structures in aqueous solution using Fourier transform IR spectroscopy

2015-02-05

Huayan Yang , Shouning Yang , Jilie Kong +2 more

Fourier Self-Deconvolution: A Method for Resolving Intrinsically Overlapped Bands

1981-05-01

Jyrki Kauppinen , Douglas J. Moffatt , Henry H. Mantsch +1 more

The general theory of Fourier self-deconvolution, i.e., spectral deconvolution using Fourier transforms and the intrinsic lineshape, is developed. The method provides a way of computationally resolving overlapped lines that can … The general theory of Fourier self-deconvolution, i.e., spectral deconvolution using Fourier transforms and the intrinsic lineshape, is developed. The method provides a way of computationally resolving overlapped lines that can not be instrumentally resolved due to their intrinsic linewidth. Examples of the application of the technique to synthetic and experimental infrared spectra are presented, and potential applications are discussed. It is shown that lines in spectra having moderate signal/noise ratios (∼1000) can readily be reduced in width by a factor of 3. The method is applicable to a variety of spectroscopic techniques.

Coherent Anti-Stokes Raman Scattering Microscopy: Instrumentation, Theory, and Applications

2003-12-25

Ji-Xin Cheng , X. Sunney Xie

Coherent anti-Stokes Raman scattering (CARS) microscopy permits vibrational imaging with high-sensitivity, high speed, and three-dimensional spatial resolution. We review recent advances in CARS microscopy, including experimental design, theoretical understanding of … Coherent anti-Stokes Raman scattering (CARS) microscopy permits vibrational imaging with high-sensitivity, high speed, and three-dimensional spatial resolution. We review recent advances in CARS microscopy, including experimental design, theoretical understanding of contrast mechanisms, and applications to chemical and biological systems. We also review the development of multiplex CARS microspectroscopy, which allows high-speed characterization of microscopic samples, and CARS correlation spectroscopy, which probes fast diffusion dynamics with vibrational selectivity.

Identification of medically relevant microorganisms by vibrational spectroscopy

2002-10-08

K. Maquelin , C. Kirschner , Lin‐P'ing Choo‐Smith +4 more

Raman microspectroscopy of soot and related carbonaceous materials: Spectral analysis and structural information

2005-03-24

A. Sadezky , H. Muckenhuber , Hinrich Grothe +2 more

Studying single living cells and chromosomes by confocal Raman microspectroscopy

1990-09-01

G.J. Puppels , Frits F. M. de Mul , Cees Otto +4 more

Prospects forin vivoRaman spectroscopy

2000-01-25

Eugene B. Hanlon , Ramasamy Manoharan , T-W Koo +7 more

Raman spectroscopy is a potentially important clinical tool for real-time diagnosis of disease and in situevaluation of living tissue. The purpose of this article is to review the biological and … Raman spectroscopy is a potentially important clinical tool for real-time diagnosis of disease and in situevaluation of living tissue. The purpose of this article is to review the biological and physical basis of Raman spectroscopy of tissue, to assess the current status of the field and to explore future directions. The principles of Raman spectroscopy and the molecular level information it provides are explained. An overview of the evolution of Raman spectroscopic techniques in biology and medicine, from early investigations using visible laser excitation to present-day technology based on near-infrared laser excitation and charge-coupled device array detection, is presented. State-of-the-art Raman spectrometer systems for research laboratory and clinical settings are described. Modern methods of multivariate spectral analysis for extracting diagnostic, chemical and morphological information are reviewed. Several in-depth applications are presented to illustrate the methods of collecting, processing and analysing data, as well as the range of medical applications under study. Finally, the issues to be addressed in implementing Raman spectroscopy in various clinical applications, as well as some long-term directions for future study, are discussed.

Single-pulse coherently controlled nonlinear Raman spectroscopy and microscopy

2002-08-01

Nirit Dudovich , Dan Oron , Yaron Silberberg

Automated Autofluorescence Background Subtraction Algorithm for Biomedical Raman Spectroscopy

2007-11-01

Jianhua Zhao , Harvey Lui , David I. McLean +1 more

A significant advantage of Raman spectroscopy as a noninvasive optical technique is its ability to detect subtle molecular or biochemical signatures within tissue. One of the major challenges for biomedical … A significant advantage of Raman spectroscopy as a noninvasive optical technique is its ability to detect subtle molecular or biochemical signatures within tissue. One of the major challenges for biomedical Raman spectroscopy is the removal of intrinsic autofluorescence background signals, which are usually a few orders of magnitude stronger than those arising from Raman scattering. A number of methods have been proposed for fluorescence background removal including excitation wavelength shifting, Fourier transformation, time gating, and simple or modified polynomial fitting. The single polynomial and the modified multi-polynomial fitting methods are relatively simple and effective, and thus are widely used in biological applications. However, their performance in real-time in vivo applications and low signal-to-noise ratio environments is sub-optimal. An improved automated algorithm for fluorescence removal has been developed based on modified multi-polynomial fitting, but with the addition of (1) a peak-removal procedure during the first iteration, and (2) a statistical method to account for signal noise effects. Experimental results demonstrate that this approach improves the automated rejection of the fluorescence background during real-time Raman spectroscopy and for in vivo measurements characterized by low signal-to-noise ratios.

Video-Rate Molecular Imaging in Vivo with Stimulated Raman Scattering

2010-12-02

Brian G. Saar , Christian W. Freudiger , Jay R. Reichman +3 more

Optical imaging in vivo with molecular specificity is important in biomedicine because of its high spatial resolution and sensitivity compared with magnetic resonance imaging. Stimulated Raman scattering (SRS) microscopy allows … Optical imaging in vivo with molecular specificity is important in biomedicine because of its high spatial resolution and sensitivity compared with magnetic resonance imaging. Stimulated Raman scattering (SRS) microscopy allows highly sensitive optical imaging based on vibrational spectroscopy without adding toxic or perturbative labels. However, SRS imaging in living animals and humans has not been feasible because light cannot be collected through thick tissues, and motion-blur arises from slow imaging based on backscattered light. In this work, we enable in vivo SRS imaging by substantially enhancing the collection of the backscattered signal and increasing the imaging speed by three orders of magnitude to video rate. This approach allows label-free in vivo imaging of water, lipid, and protein in skin and mapping of penetration pathways of topically applied drugs in mice and humans.

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Near‐infrared Raman spectroscopy for optical diagnosis of lung cancer

2003-09-18

Zhiwei Huang , Annette McWilliams , Harvey Lui +3 more

Raman spectroscopy is a vibrational spectroscopic technique that can be used to optically probe the molecular changes associated with diseased tissues. The objective of our study was to explore near-infrared … Raman spectroscopy is a vibrational spectroscopic technique that can be used to optically probe the molecular changes associated with diseased tissues. The objective of our study was to explore near-infrared (NIR) Raman spectroscopy for distinguishing tumor from normal bronchial tissue. Bronchial tissue specimens (12 normal, 10 squamous cell carcinoma (SCC) and 6 adenocarcinoma) were obtained from 10 patients with known or suspected malignancies of the lung. A rapid-acquisition dispersive-type NIR Raman spectroscopy system was used for tissue Raman studies at 785 nm excitation. High-quality Raman spectra in the 700-1,800 cm(-1) range from human bronchial tissues in vitro could be obtained within 5 sec. Raman spectra differed significantly between normal and malignant tumor tissue, with tumors showing higher percentage signals for nucleic acid, tryptophan and phenylalanine and lower percentage signals for phospholipids, proline and valine, compared to normal tissue. Raman spectral shape differences between normal and tumor tissue were also observed particularly in the spectral ranges of 1,000-1,100, 1,200-1,400 and 1,500-1,700 cm(-1), which contain signals related to protein and lipid conformations and nucleic acid's CH stretching modes. The ratio of Raman intensities at 1,445 to 1,655 cm(-1) provided good differentiation between normal and malignant bronchial tissue (p < 0.0001). The results of this exploratory study indicate that NIR Raman spectroscopy provides significant potential for the noninvasive diagnosis of lung cancers in vivo based on the optic evaluation of biomolecules.

Three-Dimensional Vibrational Imaging by Coherent Anti-Stokes Raman Scattering

1999-05-17

Andreas Zumbusch , Gary R. Holtom , X. Sunney Xie

A multiphoton microscopy based on coherent anti-Stokes Raman scattering is accomplished with near-infrared ultrashort laser pulses. We demonstrate vibrational imaging of chemical and biological samples with high sensitivity, high spatial … A multiphoton microscopy based on coherent anti-Stokes Raman scattering is accomplished with near-infrared ultrashort laser pulses. We demonstrate vibrational imaging of chemical and biological samples with high sensitivity, high spatial resolution, noninvasiveness, and three-dimensional sectioning capability.

Label-Free Biomedical Imaging with High Sensitivity by Stimulated Raman Scattering Microscopy

2008-12-18

Christian W. Freudiger , Wei Min , Brian G. Saar +6 more

Label-free chemical contrast is highly desirable in biomedical imaging. Spontaneous Raman microscopy provides specific vibrational signatures of chemical bonds, but is often hindered by low sensitivity. Here we report a … Label-free chemical contrast is highly desirable in biomedical imaging. Spontaneous Raman microscopy provides specific vibrational signatures of chemical bonds, but is often hindered by low sensitivity. Here we report a three-dimensional multiphoton vibrational imaging technique based on stimulated Raman scattering (SRS). The sensitivity of SRS imaging is significantly greater than that of spontaneous Raman microscopy, which is achieved by implementing high-frequency (megahertz) phase-sensitive detection. SRS microscopy has a major advantage over previous coherent Raman techniques in that it offers background-free and readily interpretable chemical contrast. We show a variety of biomedical applications, such as differentiating distributions of omega-3 fatty acids and saturated lipids in living cells, imaging of brain and skin tissues based on intrinsic lipid contrast, and monitoring drug delivery through the epidermis.

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Multiplexed imaging of surface enhanced Raman scattering nanotags in living mice using noninvasive Raman spectroscopy

2009-07-29

Cristina Zavaleta , Bryan Ronain Smith , Ian D. Walton +5 more

Raman spectroscopy is a newly developed, noninvasive preclinical imaging technique that offers picomolar sensitivity and multiplexing capabilities to the field of molecular imaging. In this study, we demonstrate the ability … Raman spectroscopy is a newly developed, noninvasive preclinical imaging technique that offers picomolar sensitivity and multiplexing capabilities to the field of molecular imaging. In this study, we demonstrate the ability of Raman spectroscopy to separate the spectral fingerprints of up to 10 different types of surface enhanced Raman scattering (SERS) nanoparticles in a living mouse after s.c. injection. Based on these spectral results, we simultaneously injected the five most intense and spectrally unique SERS nanoparticles i.v. to image their natural accumulation in the liver. All five types of SERS nanoparticles were successfully identified and spectrally separated using our optimized noninvasive Raman imaging system. In addition, we were able to linearly correlate Raman signal with SERS concentration after injecting four spectrally unique SERS nanoparticles either s.c. (R(2) = 0.998) or i.v. (R(2) = 0.992). These results show great potential for multiplexed imaging in living subjects in cases in which several targeted SERS probes could offer better detection of multiple biomarkers associated with a specific disease.

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Automated Method for Subtraction of Fluorescence from Biological Raman Spectra

2003-11-01

Chad A. Lieber , Anita Mahadevan‐Jansen

One of the challenges of using Raman spectroscopy for biological applications is the inherent fluorescence generated by many biological molecules that underlies the measured spectra. This fluorescence can sometimes be … One of the challenges of using Raman spectroscopy for biological applications is the inherent fluorescence generated by many biological molecules that underlies the measured spectra. This fluorescence can sometimes be several orders of magnitude more intense than the weak Raman scatter, and its presence must be minimized in order to resolve and analyze the Raman spectrum. Several techniques involving hardware and software have been devised for this purpose; these include the use of wavelength shifting, time gating, frequency-domain filtering, first- and second-order derivatives, and simple curve fitting of the broadband variation with a high-order polynomial. Of these, polynomial fitting has been found to be a simple but effective method. However, this technique typically requires user intervention and thus is time consuming and prone to variability. An automated method for fluorescence subtraction, based on a modification to least-squares polynomial curve fitting, is described. Results indicate that the presented automated method is proficient in fluorescence subtraction, repeatability, and in retention of Raman spectral lineshapes.

THE NITROUS OXIDE METHOD FOR THE QUANTITATIVE DETERMINATION OF CEREBRAL BLOOD FLOW IN MAN: THEORY, PROCEDURE AND NORMAL VALUES 1

1948-07-01

Seymour S. Kety , Carl F. Schmidt

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Coherent Anti-Stokes Raman Scattering Microscopy: Chemical Imaging for Biology and Medicine

2008-05-07

Conor L. Evans , X. Sunney Xie

Coherent anti-Stokes Raman scattering (CARS) microscopy is a label-free imaging technique that is capable of real-time, nonperturbative examination of living cells and organisms based on molecular vibrational spectroscopy. Recent advances … Coherent anti-Stokes Raman scattering (CARS) microscopy is a label-free imaging technique that is capable of real-time, nonperturbative examination of living cells and organisms based on molecular vibrational spectroscopy. Recent advances in detection schemes, understanding of contrast mechanisms, and developments of laser sources have enabled superb sensitivity and high time resolution. Emerging applications, such as metabolite and drug imaging and tumor identification, raise many exciting new possibilities for biology and medicine.

Chemical imaging of tissue in vivo with video-rate coherent anti-Stokes Raman scattering microscopy

2005-11-01

Conor L. Evans , Eric O. Potma , Mehron Puoris’haag +3 more

Imaging living organisms with molecular selectivity typically requires the introduction of specific labels. Many applications in biology and medicine, however, would significantly benefit from a noninvasive imaging technique that circumvents … Imaging living organisms with molecular selectivity typically requires the introduction of specific labels. Many applications in biology and medicine, however, would significantly benefit from a noninvasive imaging technique that circumvents such exogenous probes. In vivo microscopy based on vibrational spectroscopic contrast offers a unique approach for visualizing tissue architecture with molecular specificity. We have developed a sensitive technique for vibrational imaging of tissues by combining coherent anti-Stokes Raman scattering (CARS) with video-rate microscopy. Backscattering of the intense forward-propagating CARS radiation in tissue gives rise to a strong epi-CARS signal that makes in vivo imaging possible. This substantially large signal allows for real-time monitoring of dynamic processes, such as the diffusion of chemical compounds, in tissues. By tuning into the CH 2 stretching vibrational band, we demonstrate CARS imaging and spectroscopy of lipid-rich tissue structures in the skin of a live mouse, including sebaceous glands, corneocytes, and adipocytes, with unprecedented contrast at subcellular resolution.

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Ultrasensitive Chemical Analysis by Raman Spectroscopy

1999-09-28

Katrin Kneipp , Harald Kneipp , Irving Itzkan +2 more

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTUltrasensitive Chemical Analysis by Raman SpectroscopyKatrin Kneipp, Harald Kneipp, Irving Itzkan, Ramachandra R. Dasari, and Michael S. FeldView Author Information Physics Department, Technical University Berlin, D 10623 … ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTUltrasensitive Chemical Analysis by Raman SpectroscopyKatrin Kneipp, Harald Kneipp, Irving Itzkan, Ramachandra R. Dasari, and Michael S. FeldView Author Information Physics Department, Technical University Berlin, D 10623 Berlin, Germany, and G. R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 Cite this: Chem. Rev. 1999, 99, 10, 2957–2976Publication Date (Web):September 28, 1999Publication History Received17 February 1999Revised25 August 1999Published online28 September 1999Published inissue 13 October 1999https://pubs.acs.org/doi/10.1021/cr980133rhttps://doi.org/10.1021/cr980133rresearch-articleACS PublicationsCopyright © 1999 American Chemical SocietyRequest reuse permissionsArticle Views14795Altmetric-Citations1917LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Colloidal particles,Molecules,Nanoparticles,Raman spectroscopy,Silver Get e-Alerts

Using Raman spectroscopy to characterize biological materials

2016-03-10

Holly J. Butler , Lorna Ashton , Benjamin Bird +7 more

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Vibrational spectroscopic imaging of living systems: An emerging platform for biology and medicine

2015-11-26

Ji‐Xin Cheng , X. Sunney Xie

Vibrational spectroscopy has been extensively applied to the study of molecules in gas phase, in condensed phase, and at interfaces. The transition from spectroscopy to spectroscopic imaging of living systems, … Vibrational spectroscopy has been extensively applied to the study of molecules in gas phase, in condensed phase, and at interfaces. The transition from spectroscopy to spectroscopic imaging of living systems, which allows the spectrum of biomolecules to act as natural contrast, is opening new opportunities to reveal cellular machinery and to enable molecule-based diagnosis. Such a transition, however, involves more than a simple combination of spectrometry and microscopy. We review recent efforts that have pushed the boundary of the vibrational spectroscopic imaging field in terms of spectral acquisition speed, detection sensitivity, spatial resolution, and imaging depth. We further highlight recent applications in functional analysis of single cells and in label-free detection of diseases.

Infrared and Raman Spectroscopy

1995-02-23

AFM-IR: Technology and Applications in Nanoscale Infrared Spectroscopy and Chemical Imaging

2016-12-13

Alexandre Dazzi , Craig Prater

Atomic force microscopy-based infrared spectroscopy (AFM-IR) is a rapidly emerging technique that provides chemical analysis and compositional mapping with spatial resolution far below conventional optical diffraction limits. AFM-IR works by … Atomic force microscopy-based infrared spectroscopy (AFM-IR) is a rapidly emerging technique that provides chemical analysis and compositional mapping with spatial resolution far below conventional optical diffraction limits. AFM-IR works by using the tip of an AFM probe to locally detect thermal expansion in a sample resulting from absorption of infrared radiation. AFM-IR thus can provide the spatial resolution of AFM in combination with the chemical analysis and compositional imaging capabilities of infrared spectroscopy. This article briefly reviews the development and underlying technology of AFM-IR, including recent advances, and then surveys a wide range of applications and investigations using AFM-IR. AFM-IR applications that will be discussed include those in polymers, life sciences, photonics, solar cells, semiconductors, pharmaceuticals, and cultural heritage. In the Supporting Information, the authors provide a theoretical section that reviews the physics underlying the AFM-IR measurement and detection mechanisms.

Biological Applications of Raman Spectroscopy

2000-09-25

Thomas G. Spiro

Introduction to infrared and Raman spectroscopy

1991-01-01

Upali A. Jayasooriya

Raman Spectroscopy of Biological Tissues

2007-09-01

Zanyar Movasaghi , Shazza Rehman , Ihtesham Ur Rehman

Abstract This article reviews some of the recent advances in Raman spectroscopy, in areas related to natural tissues and cell biology. It summarizes some of the most widely used peak … Abstract This article reviews some of the recent advances in Raman spectroscopy, in areas related to natural tissues and cell biology. It summarizes some of the most widely used peak frequencies and their assignments. The aim of this study is to prepare a database of molecular fingerprints, which will help researchers in defining the chemical structure of the biological tissues introducing most of the important peaks present in the natural tissues. In spite of applying different methods, there seems to be a considerable similarity in defining the peaks of identical areas of the spectra. As a result, it is believed that preparing a unique collection of the frequencies encountered in Raman spectroscopic studies can lead to significant improvements both in the quantity and quality of spectral data and their outcomes. This article is the first review of its kind to provide a precise database on the most important Raman characteristic peak frequencies for researchers aiming to analyze natural tissues by Raman spectroscopy and will especially be of considerable assistance to those who are focusing on the analysis of cancerous tissues by Raman spectroscopy.

Imprisonment of Resonance Radiation in Gases. II

1951-09-15

T. Holstein

This paper is a continuation of an earlier paper which treated the decay of resonance radiation in optically excited gases for the case of doppler-broadened radiation in plane-parallel enclosures. The … This paper is a continuation of an earlier paper which treated the decay of resonance radiation in optically excited gases for the case of doppler-broadened radiation in plane-parallel enclosures. The treatment is here extended to a second type of enclosure geometry---infinite cylinders---and to a variety of spectral line shapes.

Infrared Absorption Spectroscopy

1964-01-01

Koji Nakanishi , Ulrich Meve , Alessandro Rapini +4 more

INFRARED AND RAMAN SPECTRA

1972-01-01

G. Herzberg

Live-Cell Multiplexed Imaging and Chemical Sensing with Cumulene and Polyyne Allotropes

2025-06-25

X. Bai , Rui Zhang , Yueli Yang +1 more | Analytical Chemistry

Visualizing a large number of species in living systems is essential for understanding complex life processes. With unique vibrational spectroscopy, polyyne has demonstrated multiplexed Raman imaging through fine-tuned frequencies in … Visualizing a large number of species in living systems is essential for understanding complex life processes. With unique vibrational spectroscopy, polyyne has demonstrated multiplexed Raman imaging through fine-tuned frequencies in the cell-silent window (1800-2700 cm-1). Here, we develop new polyyne allotropes for multiplexed imaging and vibrational sensing in live cells by stimulated Raman scattering (SRS) microscopy. Cumulenes are engineered to obtain a vibrational palette with 5 distinct frequencies in the range of 1900-2050 cm-1, achieving previously inaccessible frequencies for SRS imaging. Ratiometric polyyne sensors are further developed to demonstrate multiplexed Raman sensing of both γ-glutamyl transpeptidase (GGT) and H2O2 reactive species in live cells. By combining cumulenes and polyynes, 10-color optical imaging and chemical sensing have been achieved in living cells to visualize both organelle interactions and changes of endogenous GGT/H2O2 levels under drug treatment. The development of multiplexed imaging and functional sensing with polyyne allotropes shows great potential for studying subcellular activities and interactions in live cells.

Improving Long‐Term Glucose Prediction Accuracy with Uncertainty‐Estimated ProbSparse‐Transformer

2025-06-25

Wei Huang , Ni Fan , Weiping Wang +3 more | Advanced Intelligent Systems

Accurate prediction of blood glucose (BG) with precise data recorded by continuous glucose monitoring (CGM) is essential to improve the safety of closed‐loop insulin delivery systems for diabetic patients. However, … Accurate prediction of blood glucose (BG) with precise data recorded by continuous glucose monitoring (CGM) is essential to improve the safety of closed‐loop insulin delivery systems for diabetic patients. However, predicting BG trends under long‐term prediction horizons is challenging due to the dynamic complexity of glucose changes. In this work, a ProbSparse‐Transformer model, which alleviates the long‐term error spreading effect seen in traditional autoregressive models, is developed. This model incorporates a trustworthy uncertainty‐estimation approach to reduce output variance, further improving predictive accuracy. Additionally, an open‐source benchmark is established using four public datasets and five evaluation metrics to comprehensively assess model performance. This model shows significant improvements in both short‐term (15–30 min) and long‐term (45–60 min) BG predictions. In the 60 min task, it achieves root mean square error values of 10.86, 15.33, 20.46, and 13.74 mg dL −1 across four datasets, representing a 20%–39.4% improvement over previous methods. Finally, the model on edge devices is compressed and deployed, demonstrating its potential for practical application in real CGM systems.

Noninvasive Continuous Glucose Monitoring Using Multimodal Near-Infrared, Temperature, and Pressure Signals on the Earlobe

2025-06-24

Jongdeog Kim , Bong Kyu Kim , Miryong Park +2 more | Biosensors

This study investigates a noninvasive continuous glucose monitoring (NI-CGM) system optimized for earlobe application, leveraging the site’s anatomical advantages—absence of bone, muscle, and thick skin—for enhanced optical transmission. The system … This study investigates a noninvasive continuous glucose monitoring (NI-CGM) system optimized for earlobe application, leveraging the site’s anatomical advantages—absence of bone, muscle, and thick skin—for enhanced optical transmission. The system integrates multimodal sensing, combining near-infrared (NIR) diffuse transmission with temperature and pressure sensors. A novel Multi-Wavelength Slope Efficiency Near-Infrared Spectroscopy (MW-SE-NIRS) method is introduced, enhancing noise robustness through the slope efficiency-based parameterization of NIR signal dynamics. By employing three NIR wavelengths with distinct scattering and absorption properties, the method improves glucose detection reliability, addressing tissue heterogeneity and physiological noise in noninvasive monitoring. To validate the feasibility, a pilot clinical trial enrolled five participants with normal or pre-diabetic glucose profiles. Continuous glucose data capturing pre- and postprandial variations were analyzed using a 1D convolutional neural network (Conv1D). For three subjects under stable physiological conditions, the model achieved 97.0% Clarke error grid (CEG) A-Zone accuracy and a mean absolute relative difference (MARD) of 5.2%. Across all participants, results showed 90.9% CEG A-Zone accuracy and a MARD of 8.4%, with performance variations linked to individual factors such as earlobe thickness variability and physical activity. These outcomes demonstrate the potential of the MW-SE-NIRS system for noninvasive glucose monitoring and highlight the importance of future work on personalized modeling, sensor optimization, and larger-scale clinical validation.

Modifications of Cytochrome c by Retinoic Acid Play a Crucial Role in Mitochondrial Dysfunction of Triple-Positive Human Breast Cancer Cells: Raman Spectroscopy and Imaging Study

2025-06-24

Halina Abramczyk , Monika Kopeć , Jakub Surmacki | ACS Omega

Surface-Enhanced Raman Spectroscopy (SERS) Method for Rapid Detection of Neomycin and Chloramphenicol Residues in Chicken Meat

2025-06-24

Yan Wu , Junshi Huang , Nanwei Tong +5 more | Sensors

In the process of chicken breeding, there has been a great deal of abuse of antibiotics. Antibiotics can enter the human body along with the chicken meat, comprising a possible … In the process of chicken breeding, there has been a great deal of abuse of antibiotics. Antibiotics can enter the human body along with the chicken meat, comprising a possible risk to human health. In this paper, principal component analysis (PCA)–linear discriminant analysis (LDA) was chosen to classify neomycin (NEO) and chloramphenicol (CAP) residues in chicken meat. A total of 400 chicken meat samples were used for the classification, of which 268 samples and 132 samples were used as the training sets and the test sets, respectively. The experimental condition of SERS spectrum collection was optimized, including the use of a gold colloid and active agent, and an improvement in the adsorption time. The optimal measurement conditions for the SERS spectra were an adsorption time of 4 min and the use of a 14th-generation gold colloid as the enhanced substrate without a surfactant. For three groups of different spectral preprocessing methods, the classification accuracies of PCA-LDA models for test sets were 78.79% for baseline correction, 84.85% for the second derivative and 100% for the second derivative combined with baseline correction. LDA was used to establish a classification model to realize the quick determination of NEO and CAP residues in chicken meat by SERS. The results showed that the characteristic peaks at 546 and 666 cm−1 could be used to distinguish NEO and CAP residues in chicken meat. The classification model based on PCA-LDA had higher classification accuracy, sensitivity and specificity using a second derivative combined with baseline correction as the spectral preprocessing method, which shows that the SERS method based on PCA-LDA could be used to perform the classification of NEO and CAP residues in chicken meat quickly and effectively. It also verified the feasibility of PCA-LDA to effectively classify chicken meat samples into four types. This research method could provide a reference for the measurement of such antibiotic residues in chicken meat in the future.

Ultrasound Elastography in Prostate Diseases: Current Status and Future Directions—A Review

2025-06-24

J LIANG , Yun-xin Zhao | Journal of Clinical Ultrasound

ABSTRACT Prostate diseases, including prostate cancer and benign prostatic hyperplasia, have become significant threats to men's health. Accurate and reliable diagnostic methods are critical for early detection and timely intervention. … ABSTRACT Prostate diseases, including prostate cancer and benign prostatic hyperplasia, have become significant threats to men's health. Accurate and reliable diagnostic methods are critical for early detection and timely intervention. Although current imaging modalities such as conventional transrectal ultrasound, computed tomography, and magnetic resonance imaging play a crucial role in the diagnosis and treatment monitoring of prostate diseases, they remain hampered by certain limitations that prevent them from comprehensively and precisely addressing clinical demands. Ultrasound elastography (UE), as a rapidly emerging medical imaging technology, is gradually demonstrating broad application prospects in the diagnosis and treatment monitoring of prostate diseases. Numerous studies have validated the efficacy of UE in the diagnosis of prostate diseases, demonstrating its significant advantages in diagnostic accuracy and reduced invasiveness compared with conventional methods. Nevertheless, challenges persist in translating UE into routine clinical practice, such as the lack of standardized protocols, variability in result interpretation, and limited equipment availability. This article reviews the role of UE in the diagnosis and treatment monitoring of prostate diseases, critically evaluates its clinical potential and challenges, and serves as a reference for future in‐depth research and clinical applications.

Angularly Resolved Tip‐Enhanced Raman Spectroscopy

2025-06-23

Felix Schneider , Tim Parker , Liangxuan Wang +7 more | Angewandte Chemie

Despite intensive research in tip‐enhanced Raman spectroscopy (TERS), the angular distribution of Raman scattering in the TERS gap remains experimentally unreported leaving its relevance to the TERS signal formation to … Despite intensive research in tip‐enhanced Raman spectroscopy (TERS), the angular distribution of Raman scattering in the TERS gap remains experimentally unreported leaving its relevance to the TERS signal formation to be seldomly discussed. Here, we investigate the angular distribution of the tip‐enhanced Raman signal in the Fourier plane using a model system composed of flat‐lying cobalt (II) hexadecafluoro‐phthalocyanine (CoPcF16) molecules physically adsorbed on a smooth gold surface. Both in‐plane and out‐of‐plane vibrational modes are observed, where the out‐of‐plane Raman modes at about 678 cm‐1 and 740 cm‐1 have different angular intensity distributions than those of in‐plane Raman modes at 1309 cm‐1 and 1373 cm‐1. We interpret the angular spectrum of the TERS signal considering the molecular vibrational modes computed with density functional theory (DFT) for the free and gold‐deposited, and the directed Raman scattering by the gap‐mode predicted by Finite‐Difference Time‐Domain (FDTD) simulations. We contend that the TERS gap directs the Raman vibrational modes differently, leading to distinct angularly distributed Raman scattering intensities. These findings emphasize the non‐negligible role of the TERS detection scheme in understanding spectral features, such as the relative peak intensity ratio variations for studying molecular orientations, or for monitoring chemical reactions.

Investigating Raman Backscattering Decay and the Perspective of Time-Multiplexed Quantum Communications

2025-06-23

Pierre-Enguerrand Verdier , Romain Alléaume , Thomas J Rivera | Optics Express

Does a SPR-Based Cell-Based Assay Provide Reliable Results on the Toxicity and Efficacy of Antiviral Drugs?

2025-06-23

Petia Genova-Kalоu , E. Belina , Todor Kereziev +5 more | Sensors

SPR has been recently established as a powerful tool for studying various cellular processes in real time and without the use of labeling agents. So far, all studies in this … SPR has been recently established as a powerful tool for studying various cellular processes in real time and without the use of labeling agents. So far, all studies in this area have been performed using the Kretschmann method for SPR excitation. In our studies, we used grating-based SPR. Here, we investigated the feasibility of this approach in a cell-based assay applied for antiviral drug screening. It was found that the continuous-flow SPR detection used in the conventional SPR can be replaced by sequential signal measurements of SPR slides removed from the medium at fixed hours after seeding. A protocol ensuring correct measurements was established. SPR detection was performed up to 48 h after seeding the VERO E6 cell line in three experiments, in which the cells were (i) compound-untreated, (ii) compound-treated, and (iii) infected with human coronavirus type 229E and compound-treated. Therefore, the temporal variation in the SPR signal was determined, induced by the cell coverage on the slide, the compound toxicity, and its antiviral action. MTT analysis and microscopic observations were used as reference methods. The remarkable agreement found in the results of SPR detection proved the effectiveness and reliability of grating-based SPR applied in cell-based assays.

Angularly Resolved Tip‐Enhanced Raman Spectroscopy

2025-06-23

Felix Schneider , Tim Parker , Liangxuan Wang +7 more | Angewandte Chemie International Edition

Despite intensive research in tip-enhanced Raman spectroscopy (TERS), the angular distribution of Raman scattering in the TERS gap remains experimentally unreported leaving its relevance to the TERS signal formation to … Despite intensive research in tip-enhanced Raman spectroscopy (TERS), the angular distribution of Raman scattering in the TERS gap remains experimentally unreported leaving its relevance to the TERS signal formation to be seldomly discussed. Here, we investigate the angular distribution of the tip-enhanced Raman signal in the Fourier plane using a model system composed of flat-lying cobalt (II) hexadecafluoro-phthalocyanine (CoPcF16) molecules physically adsorbed on a smooth gold surface. Both in-plane and out-of-plane vibrational modes are observed, where the out-of-plane Raman modes at about 678 cm-1 and 740 cm-1 have different angular intensity distributions than those of in-plane Raman modes at 1309 cm-1 and 1373 cm-1. We interpret the angular spectrum of the TERS signal considering the molecular vibrational modes computed with density functional theory (DFT) for the free and gold-deposited, and the directed Raman scattering by the gap-mode predicted by Finite-Difference Time-Domain (FDTD) simulations. We contend that the TERS gap directs the Raman vibrational modes differently, leading to distinct angularly distributed Raman scattering intensities. These findings emphasize the non-negligible role of the TERS detection scheme in understanding spectral features, such as the relative peak intensity ratio variations for studying molecular orientations, or for monitoring chemical reactions.

Disentangling Temperature-Induced Variations in Absorption and Refractive Index in Ultrafast Transient Reflection Spectroscopy

2025-06-23

Lijie Wang , Yafeng Xu , Omar F. Mohammed | The Journal of Physical Chemistry Letters

Accurately interpreting ultrafast carrier dynamics in solid-state materials requires understanding the distinct contributions of absorption and refractive index variations to transient optical responses. In this study, we systematically disentangle temperature-induced … Accurately interpreting ultrafast carrier dynamics in solid-state materials requires understanding the distinct contributions of absorption and refractive index variations to transient optical responses. In this study, we systematically disentangle temperature-induced changes in the absorption coefficient and refractive index of silicon crystals as a model system. Our approach utilizes transient reflection spectroscopy, complemented by in situ temperature-dependent spectroscopic ellipsometry and density functional theory (DFT) calculations. We examine and decipher the observed spectral shifts and profile modifications in correlation with lattice expansion from 298 to 403 K. Our findings reveal that thermal-induced variations in the refractive index account for approximately 85% of the transient reflection signal at 0.2 ps in the visible range, rising to about 93% at 10 ps. This behavior is attributed to temperature-driven modifications in the band structure at the Γ and X points, inducing significant changes in the dielectric function. These changes distinctly impact absorption and refractive index, each exhibiting unique spectral signatures and temporal behaviors. This work establishes a framework for decoupling optical parameters in transient measurements, providing valuable insights for the study of solid-state optoelectronic materials.

Memorial Article: Journal of Quantitative Spectroscopy and Radiative Transfer

2025-06-22

Ali Serpengüzel , Sung-Wen Chang , Grace D. Metcalfe +3 more | WORLD SCIENTIFIC eBooks

Detecting Early Changes in Cartilage Collagen and Proteoglycans Distribution Gradients in Mice Harboring the R992C Collagen II Mutant Using 2D Correlation Infrared Spectroscopy

2025-06-22

Jolanta Fertala , Andrzej Steplewski , Andrzej Fertala | Biophysica

Collagen II is a vital structural component in developing bones and mature cartilage. Mutations in this protein cause spondyloepiphyseal dysplasia, a disease characterized primarily by altered skeletal growth and manifesting … Collagen II is a vital structural component in developing bones and mature cartilage. Mutations in this protein cause spondyloepiphyseal dysplasia, a disease characterized primarily by altered skeletal growth and manifesting with a range of phenotypes, from lethal to mild. This study examined transgenic mice harboring the R992C (p.R1124C) substitution in collagen II. Previous research demonstrated significant growth abnormalities and disorganized growth plate structure in these mice, and histological signs of osteoarthritic changes in the knee joints of 9-month-old mice with the R992C mutation. Our study focuses on detecting early structural changes in the articular cartilage that occur before histological signs become apparent. Through microscopic and spectroscopic analyses, we observed significant alterations in the distribution gradients of collagenous proteins and proteoglycans in the cartilage of R992C mutant mice. We propose that these early changes, eventually leading to articular cartilage degeneration in older mice, underscore the progressive nature of osteoarthritic changes linked to collagen II mutations. By identifying these early structural aberrations, our findings emphasize the importance of early detection of osteoarthritic changes, potentially facilitating timely, non-surgical interventions.

The Utility of Fourier Transform Infrared Spectroscopy (<scp>FTIR</scp>) for Detecting Exercise‐Induced Changes in the Human Hand Epidermis

2025-06-22

Paweł Król , Zbigniew Obmiński , Adam Reich +6 more | Journal of Biophotonics

ABSTRACT The literature lacks data on transient infrared spectral changes in the epidermis following physical exercise. This study tested the hypothesis that a single exercise session affects selected spectral bands … ABSTRACT The literature lacks data on transient infrared spectral changes in the epidermis following physical exercise. This study tested the hypothesis that a single exercise session affects selected spectral bands (3270–1045 cm −1 ) in healthy individuals. Eight professional tennis players completed a 1.5‐h moderate‐intensity training session. Epidermal samples from the inner hand were collected before and after exercise, following cleaning with distilled water and 96% PA ethyl alcohol. Samples were analyzed using Fourier Transform Infrared Spectroscopy (FTIR). Absorbance values were recorded for 12 peaks. Significant correlations were observed for the 3270 cm −1 ( r = 0.976) and 1045 cm −1 ( r = 0.754) peaks. Notably, post‐exercise increases were found at 1453 cm −1 (lipids/proteins), 1078 cm −1 (phospholipids), and 1045 cm −1 (carbohydrates). No significant changes were observed for other peaks, though a general upward trend appeared. Inter‐individual variability was high. FTIR may detect acute epidermal biochemical responses to exercise, especially in lipid‐ and phospholipid‐related structures.

Beyond Water Content: Unraveling Stiffness in Hydrated Materials by a Correlative Brillouin–Raman Approach

2025-06-21

Alessandra Anna Passeri , Francesco Morena , Chiara Argentati +7 more | ACS Photonics

Bacterial identification by metabolite-level interpretable surface-enhanced Raman spectroscopy

2025-06-20

Hao Chen , Rong Zhao , Xinyuan Bi +5 more | Advanced Photonics

Correlative Optical Spectroscopy and Mass Spectrometry Imaging Methodology to Visualise Drug Distribution in a Soft Tissue Section

2025-06-20

Vasundhara Tyagi , Alex Dexter , Jean‐Luc Vorng +5 more | Journal of Visualized Experiments

Quantitative Nonlinear Optical Polarimetry with High Spatial Resolution

2025-06-20

Albert Suceava , Sankalpa Hazra , Jadupati Nag +7 more | Optica

Development and Applications of Nonlinear Optical Spectroscopy: 21st ECONOS/41st ECW Meeting in Vienna (Austria)

2025-06-20

Ellen H. G. Backus , Oliver H. Heckl , Johannes Kiefer | Journal of Raman Spectroscopy

Algorithm-based intraoperative diagnosis of liver tumors using infrared spectroscopy

2025-06-20

Rimantė Bandzevičiūtė , Grit Preuße , Sascha Brückmann +7 more | Scientific Reports

Liver cancer, including hepatocellular carcinoma (HCC), cholangiocellular carcinoma (CCC), and metastases, presents diagnostic challenges during surgery due to its infiltrative nature. Accurate intraoperative classification and margin assessment are crucial for … Liver cancer, including hepatocellular carcinoma (HCC), cholangiocellular carcinoma (CCC), and metastases, presents diagnostic challenges during surgery due to its infiltrative nature. Accurate intraoperative classification and margin assessment are crucial for improving outcomes. Current methods, like frozen section analysis, are time-consuming and subjective, necessitating rapid, objective alternatives. This study assessed fiber-based attenuated total reflection infrared (ATR IR) spectroscopy combined with supervised machine learning for intraoperative liver tumor classification based on a holistic biochemical signature approach. Fresh liver tissue from 69 surgical patients was analyzed using a probe consisting of Ge ATR crystal and silver halide fibers. Supervised algorithms reliably classified normal tissue and tumor subtypes (HCC, CCC, metastases) using cross-validation and independent test sets. Normal liver tissue was distinguished primarily by differences in glycogen content and structural compactness of tumor tissue. Normal and tumor tissues were differentiated with a sensitivity of 0.89 and a specificity of 0.92. The accuracy of spectroscopic classification is 0.90. The three-group classification of tumor subtypes also yielded an average accuracy of 0.90. HCC is characterized by a higher glycogen content compared to CCC and metastases and can be identified spectroscopically with high reliability. CCC showed distinct protein-associated spectral signatures, while metastases exhibited unique profiles reflecting their different origins. In a minority of cases, misclassifications occurred, indicating potential for further refinement. Fiber-based ATR IR spectroscopy in combination with machine learning provides a rapid, objective, and highly accurate intraoperative tool for liver tumor classification. This label-free biochemical approach may enhance surgical precision and reduce recurrence risks across the full range of solid tumor entities.

Research on spatial heterodyne Raman imaging spectroscopy technology based on microlens array

2025-06-20

Jin Qin , Haiyan Luo , Zhiwei Li +1 more | Optical Engineering

Intersystem Accuracy in Continuous Glucose Monitoring: When Does This Matter?

2025-06-20

Stephanie Kim , Irl B. Hirsch | Diabetes Care

Beyond the Nucleus: Cytoplasmic Dominance in Follicular Thyroid Carcinoma Detection Using Single-Cell Raman Imaging across Multiple Devices

2025-06-19

Aurélien Pélissier , Kosuke Hashimoto , Kentaro Mochizuki +6 more | Analytical Chemistry

Cytological diagnosis of follicular thyroid carcinoma (FTC) is one of the main challenges in the field of endocrine oncology due to the absence of evident morphological indicators. Morphological abnormalities in … Cytological diagnosis of follicular thyroid carcinoma (FTC) is one of the main challenges in the field of endocrine oncology due to the absence of evident morphological indicators. Morphological abnormalities in the nucleus are typically key indicators of cancer cytopathology and are attributed to a range of biochemical alterations in nuclear components. Consequently, Raman spectroscopy has been widely used to detect cancer in various cytological samples, often identifying biochemical changes prior to observable morphological alterations. However, in the case of FTC, cytoplasmic features, such as carotenoids, cytochromes, and lipid droplets, have shown greater diagnostic relevance compared to nuclear features. This study leverages single-cell Raman imaging to explore the spatial origin of diagnostic signals in FTC and normal thyroid (NT) cells, assessing the contributions of the nucleus and cytoplasm independently. Our results demonstrate that Raman spectra from the cytoplasmic region can distinguish between FTC and NT cells with an accuracy of 84% under coculture conditions, consistently across two cell lines originated from two donors and maintaining robustness across multiple devices. In contrast, classification based on nuclear spectra achieved only 53% accuracy, suggesting that biochemical alterations in the cytoplasm play a more significant role in FTC detection than those in the nucleus. Our work elevates the promise of Raman-based cytopathology by providing complementary organelle-dependent information to traditional diagnostic methods and demonstrating transferability across different devices.

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Simultaneous diagnosis and physiological profiling of diverse respiratory pathogen infections using multimolecular signatures in infrared spectroscopy

2025-06-19

Zhouzhuo Tang , Jing Ni , Zihao Liu +2 more | Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy

Deep learning approaches for bruised mandarin orange classification by fluorescence hyperspectral imaging

2025-06-19

Ahyeong Lee , Insuck Baek , Jinse Kim +2 more | Postharvest Biology and Technology

Combined non-negative matrix factorization and Otsu method for advanced analysis of Raman hyperspectral images acquired at nano- and microscale

2025-06-18

Michał Czaja , Katarzyna Skirlińska‐Nosek , Anna Chachaj–Brekiesz +2 more | Optics Communications

Numerical Analysis of a SiN Digital Fourier Transform Spectrometer for a Non-Invasive Skin Cancer Biosensor

2025-06-18

Miguel Ángel Nava Blanco , Gerardo Castañón | Sensors

Early detection and continuous monitoring of diseases are critical to improving patient outcomes, treatment adherence, and diagnostic accuracy. Traditional melanoma diagnosis relies primarily on visual assessment and biopsy, with reported … Early detection and continuous monitoring of diseases are critical to improving patient outcomes, treatment adherence, and diagnostic accuracy. Traditional melanoma diagnosis relies primarily on visual assessment and biopsy, with reported accuracies ranging from 50% to 90% and significant inter-observer variability. Among emerging diagnostic technologies, Raman spectroscopy has demonstrated considerable promise for non-invasive disease detection, particularly in early-stage skin cancer identification. A portable, real-time Raman spectroscopy system could significantly enhance diagnostic precision, reduce biopsy reliance, and expedite diagnosis. However, miniaturization of Raman spectrometers for portable use faces significant challenges, including weak signal intensity, fluorescence interference, and inherent trade-offs between spectral resolution and the signal-to-noise ratio. Recent advances in silicon photonics present promising solutions by facilitating efficient light collection, enhancing optical fields via high-index-contrast waveguides, and allowing compact integration of photonic components. This work introduces a numerical analysis of an integrated digital Fourier transform spectrometer implemented on a silicon-nitride (SiN) platform, specifically designed for Raman spectroscopy. The proposed system employs a switch-based digital Fourier transform spectrometer architecture coupled with a single optical power meter for detection. Utilizing a regularized regression method, we successfully reconstructed Raman spectra in the 800 cm-1 to 1800 cm-1 range, covering spectra of both benign and malignant skin lesions. Our results demonstrate the capability of the proposed system to effectively differentiate various skin cancer types, highlighting its feasibility as a non-invasive diagnostic sensor.

Transfer-Learning Deep Raman Models Using Semiempirical Quantum Chemistry

2025-06-18

Jawad Kamran , Julian Hniopek , Thomas Bocklitz | Journal of Chemical Information and Modeling

Biophotonic technologies such as Raman spectroscopy are powerful tools for obtaining highly specific molecular information. Due to its minimal sample preparation requirements, Raman spectroscopy is widely used across diverse scientific … Biophotonic technologies such as Raman spectroscopy are powerful tools for obtaining highly specific molecular information. Due to its minimal sample preparation requirements, Raman spectroscopy is widely used across diverse scientific disciplines, often in combination with chemometrics, machine learning (ML), and deep learning (DL). However, Raman spectroscopy lacks large databases of independent Raman spectra for model training, leading to overfitting, overestimation, and limited model generalizability. We address this problem by generating simulated vibrational spectra using semiempirical quantum chemistry methods, enabling the efficient pretraining of deep learning models on large synthetic data sets. These pretrained models are then fine-tuned on a smaller experimental Raman data set of bacterial spectra. Transfer learning significantly reduces the computational cost while maintaining performance comparable to models trained from scratch in this real biophotonic application. The results validate the utility of synthetic data for pretraining deep Raman models and offer a scalable framework for spectral analysis in resource-limited settings.

Mode parameter recognition of high-order radial Laguerre-Gaussian beam superposition states using SKCSWT-Net

2025-06-18

Deqiang Ding , Zhixu Jia , Pengfei Wu +4 more | Optics Express

Study on the quantitative analysis of Tilianin based on Raman spectroscopy combined with deep learning

2025-06-18

Wen Jiang , Wei Liu , Xiaotong Xin +6 more | PLoS ONE

Tilianin is a commonly used pharmaceutical ingredient with various biological activities such as antioxidant, anti-inflammatory, and anticancer, which is able to exert antitumor effects by inhibiting tumor cell proliferation, inducing … Tilianin is a commonly used pharmaceutical ingredient with various biological activities such as antioxidant, anti-inflammatory, and anticancer, which is able to exert antitumor effects by inhibiting tumor cell proliferation, inducing apoptosis and inhibiting angiogenesis. Studies have demonstrated to be particularly useful in a variety of cancers such as liver, lung and gastric cancers. Quantitative analysis of Tilianin can improve the quality control of related drugs and assist in guiding clinical application and disease treatment. However, there are limited studies on the quantitative analysis of Tilianin. High performance liquid chromatography (HPLC) and mass spectrometry (MS) are commonly used methods for the quantitative analysis of the components, but they often require complex pretreatment steps and specialized analytical capabilities, and are sample-destructive. The method based on Raman spectroscopy and deep learning is a widely used non-destructive analysis method. For this reason, this paper proposes a residual self-attention mechanism model based on Raman spectroscopy and deep learning for quantitative analysis of 6 concentrations of Tilianin. Six different concentrations of Tilianin-methanol solutions were prepared, and a total of 120 spectral samples were collected, which were pre-processed and inputted into our Raman Spectrum with Self-Attention Quantification Net (RSAQN) for analyzing and predicting. The structure of this model not only focuses on the deep and shallow features of the spectrum, but also the information between different channels, and the self-attention mechanism further extracts the features and outputs the predicted values of Tilianin concentration through the fully connected layer. In this paper, five sets of comparison models are set up, including two machine learning models (Random Forest, K-Nearest Neighbors, Artificial Neural Network) and two deep learning models (Convolutional Neural Network and Variational Autoencoder), and the results show that the model in this paper fits the best, obtaining an R 2 of 0.9144, as well as a small error.

A robust support vector machine approach for Raman data classification

2025-06-18

Marco Piazza , Andrea Spinelli , Francesca Maggioni +2 more | Decision Analytics Journal

Geno-pheno characterization of crop rhizospheres: An integrated Raman spectroscopy and microbiome approach in conventional and organic agriculture

2025-06-17

Yejin Son , Ping He , Mathew Baldwin +4 more | bioRxiv (Cold Spring Harbor Laboratory)

In this study, we examined phenotypic and compositional patterns in rhizosphere microbial communities across conventionally and organically managed farms to assess impacts on soil microbiomes. We employed newly developed single-cell … In this study, we examined phenotypic and compositional patterns in rhizosphere microbial communities across conventionally and organically managed farms to assess impacts on soil microbiomes. We employed newly developed single-cell Raman microspectroscopy (SCRS)-based community phenotypic profiling analysis with microbiome 16S rRNA gene amplicon sequencing to compare the soil microbial communities of alfalfa, carrot, corn, lettuce, potato, soybean, squash, tomato, triticale, wheat, oat, and pea grown under either conventional or organic agriculture across farms in New York State (USA). Distinct microbiome clustering patterns indicated that organic and conventional production methods imposed strong selective pressures, shaping microbial assemblages within each group more distinctly than site or plant species variations. Using SCRS-based microbial phenotyping, we identified distinct microbial adaptations in agricultural soils, with organic systems favoring lipid-accumulating phenotypes for energy storage and stress resilience in low-input environments, while higher nutrient availability in conventional systems promoted carbon-rich phenotypes, enhancing rapid carbon assimilation and biomass production. Through network analysis of ecological hub species, we identified Pseudomonas, a plant growth-promoting rhizobacteria (PGPR), along with several nitrogen-fixing prokaryotes as core members within conventional agricultural systems. In contrast, organically managed soils featured PGPR taxa from the Bacilli class and contained microorganisms carrying antibiotic resistance genes, potentially indicating the presence of antibiotic resistance genes within organic agricultural environments. Overall, we found that the novel inclusion of microbial phenotyping methods, such as SCRS, can describe unique linkages between microbiome structure and their physiology that are distinctive between conventional and organic agricultural systems.

A Self-supervised Learning Method for Raman Spectroscopy based on Masked Autoencoders

2025-06-17

Pengju Ren , Ri‐Gui Zhou , Yaochong Li | Expert Systems with Applications

Development and characterization of a dual-fiber Raman probe for accurate and rapid endometrial carcinoma detection

2025-06-17

xun chen , Zhaoqin Yang , Zhichao Wang +7 more | Biomedical Optics Express

Raman micro-spectroscopy reveals the metabolic alterations in primary prostate tumor tissues of patients with metastases

2025-06-17

Xiaoguang Shao , Bo Liu , Hongyang Qian +6 more | Journal of Translational Medicine

Collaborative utilization of complementary cyanine dyes for application in broad-range NIR-absorbing films

2025-06-17

Hyun Kyu Lee , Jeong Yong Lee , Hong Mo Kim +7 more | Progress in Organic Coatings

Acousto-electric conversion fiber networks via regional activation of schwann cell-derived exosomes for neuro–bone regeneration

2025-06-16

Weiwei Yi , Xiaoyu Han , Fan Wang +7 more | Research

Neural-network extraction of unpolarised transverse-momentum-dependent distributions

2025-06-16

NULL AUTHOR_ID | Physical Review Letters

Augmentation of Infrared Microscopy of White Blood Cells and Medical Measures for Rapid and Accurate Diagnosis of Bacterial or Viral Infections in Febrile Pediatric Oncology Patients: An Expert System-Based Study

2025-06-16

Uraib Sharaha , Yotam D. Eshel , Dima Bykhovsky +6 more | Analytical Chemistry

Infectious diseases, a major contributor to high mortality rates, often exhibit similar symptoms, despite variations in immune responses to bacterial or viral infections. Rapidly differentiating bacterial infections from viral infections … Infectious diseases, a major contributor to high mortality rates, often exhibit similar symptoms, despite variations in immune responses to bacterial or viral infections. Rapidly differentiating bacterial infections from viral infections in febrile pediatric oncology patients is critical to reduce unnecessary antibiotic use and improve patient outcomes. Current diagnostic procedures require 2-4 days, prompting physicians to rely on clinical measures like C-reactive protein (CRP), white blood cell (WBC) count, and absolute neutrophil count (ANC) despite their limited specificity, leading to unnecessary antibiotic treatment. This study aims to accelerate and enhance the infection etiology prediction of bacterial or viral infections. Thus, we first evaluated the maximum achievable diagnostic accuracy using CRP, WBC, and ANC and found a success rate of approximately 70%. Additionally, we explored the potential of infrared spectroscopy of isolated WBCs by applying machine learning algorithms, which yielded a 97% classification accuracy for bacterial vs viral infections. This involved implementing various analysis strategies and employing a decision system. Finally, augmenting the infrared spectra with CRP, WBC, and ANC data further boosted diagnostic accuracy to 98.6%. This study included 50 bacterial infections, 21 viral infections, and 39 control cases for medical measures. For infrared spectroscopy, data were collected from 59 bacterial infections, 29 viral infections, and 92 controls (pediatric oncology patients without fever). These findings underscore that augmenting infrared spectroscopic data with traditional clinical measures can shorten diagnosis time to roughly 1 h, improve infection etiology determination, and potentially curb the overuse of antibiotics in vulnerable pediatric oncology populations.

Testing Spatial Modulations in a Compressive Single-Pixel Hyperspectral Microscope with Optical Fiber Light Collection

2025-06-16

Lukáš Klein , Karel Žídek | Journal of Optics

Abstract A single-pixel camera is an alternative approach to image acquisition that can, through combination with compressive sensing, significantly reduce the number of measured data points by using a set … Abstract A single-pixel camera is an alternative approach to image acquisition that can, through combination with compressive sensing, significantly reduce the number of measured data points by using a set of modulation patterns on the captured image. Various modes of spatial modulations in compressive imaging can vastly affect the measurement quality and reduce the number of measurements needed. While previous studies have explored various modulation approaches, they often examined only a limited subset under inconsistent conditions. In this work, we provide a thorough comparison of the performance of 20 different modes of modulations and their modifications using a unified testing scheme. These were implemented via a digital micromirror device (DMD), and the DMD-modulated light was collected into an optical fiber. First, we evaluated the modulation patterns through simulations to study the impact of noise on image reconstruction. Next, we experimentally tested the entire set of patterns using the previously developed dual hyperspectral compressive microscope. We observed that the experimental results were highly affected by the diffraction on DMD, which highly depended on the character of a pattern. To ensure a thorough analysis, all modulation modes were tested on three different samples and at three distinct resolutions. Additionally, we identified individual challenges and limitations associated with specific modulation modes, offering practical insights for their testing and application. This study provides valuable guidance for optimizing modulation patterns in compressive imaging systems.&#xD;

P17 Alternative optical techniques for assessing the aggressiveness of prostate cancer

2025-06-16

Alexandre Khuskivadze , S. Abazadze , Nutsa Khuskivadze +2 more | European Urology Open Science

Handheld Spatially Offset Raman Spectroscopy for Rapid Non-invasive Detection of Ethylene Glycol and Diethylene Glycol in Medicinal Syrups

2025-06-14

Sube Banerjee , Sara Mosca , Isabelle Legge +7 more | Journal of Pharmaceutical and Biomedical Analysis

Identifying Label-free and Untargeted Biomarkers of SH-SY5Y Cell Fate in ATRA-Induced Differentiation Through FTIR and Integrated Omics.

2025-06-14

Diletta Ami , Federica Bovio , Matilde Forcella +4 more | Talanta