Advances in the Application of Array Detectors for Improved Chemical Analysis, Part I. Comparison of Qualitative Analyses Using Large, Computer-Based Raman Spectral Libraries

2003 ◽  
Vol 56 (3) ◽  
pp. 117 ◽  
Author(s):  
M. Bonner Denton ◽  
Roger P. Sperline ◽  
Jeffrey H. Giles ◽  
Daniel A. Gilmore ◽  
Carolyn J. S. Pommier ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Large Computer ◽  
Analytical Technique ◽  
Minimal Sample ◽  
Array Detectors ◽  
Technical Advances ◽  
Computer Based ◽  
Spectral Libraries ◽  
Raman Spectral ◽  
Qualitative Analyses

Although a mature technique, Raman spectroscopy remains not widely used as a routine analytical technique. The advantages of Raman spectroscopy, such as minimal sample preparation and relatively uncomplicated spectra, combined with technical advances, including more stable diode lasers, higher quality filters, and better polychromators and array detectors, have led to a renaissance in sensitive and versatile Raman spectrometers. The lack of appropriate databases for routine analysis, which represents the last barrier to the technique's widespread use, is beginning to be overcome, as described in this review.

Advances in the Application of Array Detectors for Improved Chemical Analysis. Part 1. Comparison of Qualitative Analyses Using Large, Computer-Based Raman Spectral Libraries

ChemInform ◽  
2003 ◽  
Vol 34 (28) ◽  
Author(s):  
M. Bonner Denton ◽  
Roger P. Sperline ◽  
Jeffrey H. Giles ◽  
Daniel A. Gilmore ◽  
Carolyn J. S. Pommier ◽  
...  
Keyword(s):  
Chemical Analysis ◽  
Large Computer ◽  
Array Detectors ◽  
Computer Based ◽  
Spectral Libraries ◽  
Raman Spectral ◽  
Qualitative Analyses

A Simple Algorithm for Despiking Raman Spectra

2018 ◽  
Author(s):  
Darren Whitaker ◽  
Kevin Hayes
Keyword(s):  
Moving Average ◽  
Simple Algorithm ◽  
Mathematical Concepts ◽  
Charge Coupled Device ◽  
Analytical Technique ◽  
Minimal Sample ◽  
Minimal Distortion ◽  
Molecular Specificity ◽  
Ccd Detectors ◽  
Average Filter

Raman Spectroscopy is a widely used analytical technique, favoured when molecular specificity with minimal sample preparation is required.<br>The majority of Raman instruments use charge-coupled device (CCD) detectors, these are susceptible to cosmic rays and as such multiple spurious spikes can occur in the measurement. These spikes are problematic as they may hinder subsequent analysis, particularly if multivariate data analysis is required. In this work we present a new algorithm to remove these spikes from spectra after acquisition. Specifically we use calculation of modified <i>Z</i> scores to locate spikes followed by a simple moving average filter to remove them. The algorithm is very simple and its execution is essentially instantaneous, resulting in spike-free spectra with minimal distortion of actual Raman data. The presented algorithm represents an improvement on existing spike removal methods by utilising simple, easy to understand mathematical concepts, making it ideal for experts and non-experts alike. <br>

A Simple Algorithm for Despiking Raman Spectra

2018 ◽  
Author(s):  
Darren Whitaker ◽  
Kevin Hayes
Keyword(s):  
Moving Average ◽  
Simple Algorithm ◽  
Mathematical Concepts ◽  
Charge Coupled Device ◽  
Analytical Technique ◽  
Minimal Sample ◽  
Minimal Distortion ◽  
Molecular Specificity ◽  
Ccd Detectors ◽  
Average Filter

Raman Spectroscopy is a widely used analytical technique, favoured when molecular specificity with minimal sample preparation is required.<br>The majority of Raman instruments use charge-coupled device (CCD) detectors, these are susceptible to cosmic rays and as such multiple spurious spikes can occur in the measurement. These spikes are problematic as they may hinder subsequent analysis, particularly if multivariate data analysis is required. In this work we present a new algorithm to remove these spikes from spectra after acquisition. Specifically we use calculation of modified <i>Z</i> scores to locate spikes followed by a simple moving average filter to remove them. The algorithm is very simple and its execution is essentially instantaneous, resulting in spike-free spectra with minimal distortion of actual Raman data. The presented algorithm represents an improvement on existing spike removal methods by utilising simple, easy to understand mathematical concepts, making it ideal for experts and non-experts alike. <br>

A Simple Algorithm for Despiking Raman Spectra

2018 ◽  
Author(s):  
Darren Whitaker ◽  
Kevin Hayes
Keyword(s):  
Moving Average ◽  
Simple Algorithm ◽  
Mathematical Concepts ◽  
Charge Coupled Device ◽  
Analytical Technique ◽  
Minimal Sample ◽  
Minimal Distortion ◽  
Molecular Specificity ◽  
Ccd Detectors ◽  
Average Filter

Raman Spectroscopy is a widely used analytical technique, favoured when molecular specificity with minimal sample preparation is required.<br>The majority of Raman instruments use charge-coupled device (CCD) detectors, these are susceptible to cosmic rays and as such multiple spurious spikes can occur in the measurement. These spikes are problematic as they may hinder subsequent analysis, particularly if multivariate data analysis is required. In this work we present a new algorithm to remove these spikes from spectra after acquisition. Specifically we use calculation of modified <i>Z</i> scores to locate spikes followed by a simple moving average filter to remove them. The algorithm is very simple and its execution is essentially instantaneous, resulting in spike-free spectra with minimal distortion of actual Raman data. The presented algorithm represents an improvement on existing spike removal methods by utilising simple, easy to understand mathematical concepts, making it ideal for experts and non-experts alike. <br>

Spectroscopic requirements for Raman instrumentation on a planetary lander: potential for the remote detection of biosignatures on Mars

2004 ◽  
Vol 3 (2) ◽  
pp. 165-174 ◽  
Author(s):  
S.E. Jorge Villar ◽  
H.G.M. Edwards
Keyword(s):  
Raman Spectroscopy ◽  
Raman Spectra ◽  
Spectral Resolution ◽  
Detection Sensitivity ◽  
Remote Detection ◽  
Spectral Identification ◽  
Scan Time ◽  
Time Parameters ◽  
Raman Spectral ◽  
Non Destructive

The special characteristics of Raman spectroscopy (relative insensitivity to water, non-destructive detection, sensitivity to bio- and geosignatures, molecular structural composition information, etc.) together with the development of miniaturized Raman spectrometers make the consideration of this technique for future robotic landers on planetary surfaces, particularly Mars, a very interesting option. The development of light and rugged Raman spectrometers limits the possible scope of the instrumentation which has particular importance in the recognition of biomolecular and mineral signatures. In this work, we evaluate the spectral resolution and scan time parameters and the effect that they have on the Raman spectra of extremophilic biomolecules, together with the wavenumber ranges which are critical for the detection of life signals. This is of vital relevance for the design of miniaturized Raman spectrometer systems. From our results, we conclude that for extraterrestrial biological signatures unambiguous Raman spectral identification provided with a minimum of 16 cm−1 spectral resolution is required for the most significant biosignature wavenumber range in the 1700–700 cm−1 region.

Raman spectral analysis of nasopharyngeal carcinoma cell line CNE2 after microwave radiation

2013 ◽  
Vol 91 (2) ◽  
pp. 67-71 ◽  
Author(s):  
Yuhuang Ye ◽  
Yang Chen ◽  
Ying Su ◽  
Changyan Zou ◽  
Yangwen Huang ◽  
...  
Keyword(s):  
Support Vector Machine ◽  
Raman Spectroscopy ◽  
Nasopharyngeal Carcinoma ◽  
Microwave Radiation ◽  
Principal Components ◽  
Carcinoma Cell ◽  
Support Vector ◽  
Components Analysis ◽  
Raman Spectral ◽  
Radiation Time

This study aimed to study the effects of microwave radiation on the nasopharyngeal carcinoma cell line CNE2 by Raman spectroscopy. The cells were separated into a control group and radiated groups with radiation times of 2, 5, 10, and 25 min, respectively. Both principal components analysis and support vector machine were employed for statistical analysis of Raman spectra. The results show that the relative content of C-H deformation and amide I begin to change when the radiation time is over 10 min, and principal components analysis further confirms there are significant differences after 10 min of radiation. Moreover, support vector machine is simultaneously used to classify radiated samples from control samples. The classification accuracy is low until the radiation time reaches over 10 min. In conclusion, this study reveals the Raman spectral characteristics of CNE2 under different microwave radiation exposure timesand demonstrates Raman spectroscopy can be a potential method to explore cellular characterization after radiation. The final results may help in elucidating the mechanism by which microwave radiation interacts with tumor cells.

scholarly journals Investigation on the Cancer Invasion and Metastasis of Skin Squamous Cell Carcinoma by Raman Spectroscopy

Molecules ◽  
2019 ◽  
Vol 24 (11) ◽  
pp. 2059 ◽  
Author(s):  
Xu Zhang ◽  
Fan Yu ◽  
Jie Li ◽  
Dongliang Song ◽  
Heping Li ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Squamous Cell Carcinoma ◽  
Cell Carcinoma ◽  
Squamous Cell ◽  
Biological Information ◽  
Skin Squamous Cell Carcinoma ◽  
Cancer Field ◽  
Hematoxylin And Eosin ◽  
Raman Spectral

Raman spectroscopy facilitates accurate and minimally invasive investigation on biomedical samples to reveal their molecular-level biological information. In this work, the cancer field effects of squamous cell carcinoma (SCC) tissues were illustrated by Raman microspectroscopy. Referenced with hematoxylin and eosin (H&E) stained microscopic images, the biochemical variations during SCC progress were meticulously described by the Raman spectral features in different pathological areas of two lesion types, including the biochemical changes in collagen, lipids, DNA, and other components of SCC diffusion and metastasis. The experimental results demonstrated that the intensities of the Raman peaks representing collagen (853, 936, and 1248 cm−1) were decreased, whereas the intensities of peaks corresponding to DNA (720, 1327 cm−1) and lipids (1305 cm−1) were increased significantly in cancerous lesions, which testified that SCC originates from the epidermis and invades the dermis gradually. The achieved results not only described the molecular mechanism of skin carcinogenesis, but also provided vital reference data for in vivo skin cancer diagnosis using Raman spectroscopy.

scholarly journals Coral calcifying fluid aragonite saturation states derived from Raman spectroscopy

2017 ◽  
Vol 14 (22) ◽  
pp. 5253-5269 ◽  
Author(s):  
Thomas M. DeCarlo ◽  
Juan P. D'Olivo ◽  
Taryn Foster ◽  
Michael Holcomb ◽  
Thomas Becker ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
High Resolution ◽  
Ocean Acidification ◽  
Environmental Changes ◽  
Isotope Geochemistry ◽  
Strong Dependence ◽  
Saturation State ◽  
Minimal Sample ◽  
Biomineralization Process ◽  
Elevated Co2 And Temperature

Abstract. Quantifying the saturation state of aragonite (ΩAr) within the calcifying fluid of corals is critical for understanding their biomineralization process and sensitivity to environmental changes including ocean acidification. Recent advances in microscopy, microprobes, and isotope geochemistry enable the determination of calcifying fluid pH and [CO32−], but direct quantification of ΩAr (where ΩAr =  [CO32−][Ca2+]∕Ksp) has proved elusive. Here we test a new technique for deriving ΩAr based on Raman spectroscopy. First, we analysed abiogenic aragonite crystals precipitated under a range of ΩAr from 10 to 34, and we found a strong dependence of Raman peak width on ΩAr with no significant effects of other factors including pH, Mg∕Ca partitioning, and temperature. Validation of our Raman technique for corals is difficult because there are presently no direct measurements of calcifying fluid ΩAr available for comparison. However, Raman analysis of the international coral standard JCp-1 produced ΩAr of 12.3 ± 0.3, which we demonstrate is consistent with published skeletal Mg∕Ca, Sr∕Ca, B∕Ca, δ11B, and δ44Ca data. Raman measurements are rapid ( ≤  1 s), high-resolution ( ≤  1 µm), precise (derived ΩAr ± 1 to 2 per spectrum depending on instrument configuration), accurate ( ±2 if ΩAr < 20), and require minimal sample preparation, making the technique well suited for testing the sensitivity of coral calcifying fluid ΩAr to ocean acidification and warming using samples from natural and laboratory settings. To demonstrate this, we also show a high-resolution time series of ΩAr over multiple years of growth in a Porites skeleton from the Great Barrier Reef, and we evaluate the response of ΩAr in juvenile Acropora cultured under elevated CO2 and temperature.

Advances in the Application of Array Detectors for Improved Chemical Analysis, Part II. Rapid Trace Metal Analysis of High Solids Wastewater and Sludge Using a Direct Current Plasma Source Equipped with an Echelle Spectrometer and a Charge-Injection Device Detector

2003 ◽  
Vol 56 (3) ◽  
pp. 133 ◽  
Author(s):  
Jeff Prevatt ◽  
M. Bonner Denton
Keyword(s):  
Trace Metals ◽  
Direct Current ◽  
Charge Injection ◽  
Plasma Source ◽  
High Solids ◽  
Injection Device ◽  
Analytical Technique ◽  
Array Detectors ◽  
Direct Current Plasma ◽  
Echelle Spectrometer

A direct current plasma (DCP) source, equipped with an echelle spectrometer and charge-injection device (CID) detector, was employed for the analysis of trace metals in municipal sludge and wastewater containing high solids. The use of DCP as a plasma source has largely vanished in the past decade due to the popularity of inductively coupled plasma. Resurrecting this robust plasma source and coupling it to a state-of-the-art echelle spectrometer provides for an extremely forgiving analytical technique capable of analysing trace metals rapidly, even in complex high-solid matrices. Instrument performance is further enhanced as the echelle/CID spectrometer provides a simultaneous multi-element fingerprint of contaminants in the waste. The improved design offers increased sensitivity in the far ultraviolet, with overall wavelength coverage from 175 to 800 nm. Furthermore, multi-element analysis is obtained quickly with minimal or no sample preparation, making this the fastest screening technique available.

Sign in / Sign up

Export Citation Format

Share Document