Raman spectral titration method: an informative technique for studying the complexation of uranyl with uranyl(vi)–DPA/oxalate systems as examples

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.

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

Biochemistry and Cell Biology ◽

10.1139/bcb-2012-0040 ◽

2013 ◽

Vol 91 (2) ◽

pp. 67-71 ◽

Cited By ~ 1

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.

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

Molecules ◽

10.3390/molecules24112059 ◽

2019 ◽

Vol 24 (11) ◽

pp. 2059 ◽

Cited By ~ 3

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.

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Raman Spectral Characterization of Pure and Doped Fused Silica Optical Fibers

Applied Spectroscopy ◽

10.1366/000370275774455969 ◽

1975 ◽

Vol 29 (4) ◽

pp. 337-344 ◽

Cited By ~ 66

Author(s):

G. E. Walrafen ◽

J. Stone

Keyword(s):

Raman Spectroscopy ◽

Raman Spectra ◽

Optical Fibers ◽

Fused Silica ◽

Laser Raman ◽

Laser Raman Spectra ◽

Raman Spectral ◽

Oh Content ◽

Absorption Measurements

The utility of Raman spectroscopy as a means of characterizing the properties of pure and doped fused silica has been investigated. Laser-Raman spectra were obtained by forward scattering from solid optical fibers ∼35 to 85 m in length using 514.5 nm excitation with an “image slicer” and a Cary model 81 instrument. Clad and unclad fibers of fused silica and doped fibers having SiO2-GeO2 and SiO2-GeO2-B2O3 cores were examined. Raman spectra were also obtained from bulk samples of glasses, including pure GeO2, pure B2O3, and various compositions of SiO2-GeO2, SiO2-B2O3, and SiO2-GeO2-B2O3. The addition of dopants to fused silica was found to alter the Raman spectrum both by the appearance of new bands, roughly proportional to dopant concentration and not common either to the fused silica or to the dopant alone, and by the marked alteration of other Raman bands, which is indicative of changes in the local intermolecular order. Thus, addition of GeO2 produces new Raman bands at ∼675 and ∼1000 cm−1; and of B2O3, new bands at ∼940 and ∼1350 cm−1. Addition of GeO2 and/or B2O3 weakens the relatively sharp Raman lines near 485 and 600 cm−1 (and a similar but small effect was also noted with increasing OH content). GeO2 and B2O3 together also produce observable narrowing of the broad intense 440 cm−1 Raman contour. These spectral effects are interpreted, respectively, in terms of a decrease in the concentrations of [Formula: see text] and [Formula: see text] defects produced by dopant addition and of a concomitant reordering of the silica structure. Raman spectroscopy thus appears to be a useful optical technique for elucidating the properties of dopants that have been especially chosen for good optical transmission and hence are not easily detectable by absorption measurements.

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Raman Spectroscopy Combined with Principal Component Analysis for Screening Nasopharyngeal Cancer in Human Blood Sera

Applied Spectroscopy ◽

10.1177/0003702817723928 ◽

2017 ◽

Vol 71 (11) ◽

pp. 2497-2503 ◽

Cited By ~ 11

Author(s):

Saranjam Khan ◽

Rahat Ullah ◽

Samina Javaid ◽

Shaheen Shahzad ◽

Hina Ali ◽

...

Keyword(s):

Principal Component Analysis ◽

Raman Spectroscopy ◽

Human Blood ◽

Nasopharyngeal Cancer ◽

Principal Component ◽

Component Analysis ◽

Data Sets ◽

Analysis Technique ◽

Raman Spectral Data ◽

Raman Spectral

This study demonstrates the analysis of nasopharyngeal cancer (NPC) in human blood sera using Raman spectroscopy combined with the multivariate analysis technique. Blood samples of confirmed NPC patients and healthy individuals have been used in this study. The Raman spectra from all these samples were recorded using 785 nm laser for excitation. Important Raman bands at 760, 800, 815, 834, 855, 1003, 1220–1275, and 1524 cm−1, have been observed in both normal and NPC samples. A decrease in the lipids content, phenylalanine, and β-carotene, whereas increases in amide III, tyrosine, and tryptophan have been observed in the NPC samples. The two data sets were well separated using principal component analysis (PCA) based on Raman spectral data. The spectral variations between the healthy and cancerous samples have been further highlighted by plotting loading vectors PC1 and PC2, which shows only those spectral regions where the differences are obvious.

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Rapid Detection and Quantification of Plant Innate Immunity Response Using Raman Spectroscopy

Frontiers in Plant Science ◽

10.3389/fpls.2021.746586 ◽

2021 ◽

Vol 12 ◽

Author(s):

Pil Joong Chung ◽

Gajendra P. Singh ◽

Chung-Hao Huang ◽

Sayuj Koyyappurath ◽

Jun Sung Seo ◽

...

Keyword(s):

Raman Spectroscopy ◽

Innate Immunity ◽

Quantitative Measure ◽

Raman Shift ◽

Regulatory Mutants ◽

Response Index ◽

Spectral Bands ◽

Elicitor Response ◽

Raman Spectral ◽

Detection And Quantification

We have developed a rapid Raman spectroscopy-based method for the detection and quantification of early innate immunity responses in Arabidopsis and Choy Sum plants. Arabidopsis plants challenged with flg22 and elf18 elicitors could be differentiated from mock-treated plants by their Raman spectral fingerprints. From the difference Raman spectrum and the value of p at each Raman shift, we derived the Elicitor Response Index (ERI) as a quantitative measure of the response whereby a higher ERI value indicates a more significant elicitor-induced immune response. Among various Raman spectral bands contributing toward the ERI value, the most significant changes were observed in those associated with carotenoids and proteins. To validate these results, we investigated several characterized Arabidopsis pattern-triggered immunity (PTI) mutants. Compared to wild type (WT), positive regulatory mutants had ERI values close to zero, whereas negative regulatory mutants at early time points had higher ERI values. Similar to elicitor treatments, we derived an analogous Infection Response Index (IRI) as a quantitative measure to detect the early PTI response in Arabidopsis and Choy Sum plants infected with bacterial pathogens. The Raman spectral bands contributing toward a high IRI value were largely identical to the ERI Raman spectral bands. Raman spectroscopy is a convenient tool for rapid screening for Arabidopsis PTI mutants and may be suitable for the noninvasive and early diagnosis of pathogen-infected crop plants.

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Plasmon induced enhancement of surface optical phonon modes and magnon properties of NiO nanoparticles: Raman spectral probe

Physical Chemistry Chemical Physics ◽

10.1039/d0cp03720f ◽

2020 ◽

Vol 22 (39) ◽

pp. 22815-22822 ◽

Cited By ~ 1

Author(s):

Anoop Sunny ◽

Karthikeyan Balasubramanian

Keyword(s):

Raman Spectroscopy ◽

Optical Phonon ◽

Room Temperature ◽

Nio Nanoparticles ◽

Phonon Modes ◽

Surface Optical ◽

Raman Spectral

In the present work, the influence of Ag-induced plasmons on the surface optical (SO) phonon modes of NiO nanoparticles was extensively studied using room temperature Raman spectroscopy.

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Raman Spectral Trends in ‘low-temperature’ Carbonaceous Materials.

10.5194/egusphere-egu21-7939 ◽

2021 ◽

Author(s):

David Muirhead

Keyword(s):

Raman Spectroscopy ◽

Low Temperature ◽

Amorphous Carbon ◽

Carbonaceous Material ◽

Carbonaceous Materials ◽

Chemical Mechanisms ◽

Thrust Belts ◽

Temperature Ranges ◽

Host Rocks ◽

Raman Spectral

<p>Amorphous carbonaceous materials are typically those that would be considered immature, at temperatures below 300&#176;C, in a typical sedimentary basin burial setting. Only recently has there been much discussion on the efficacy of Raman spectroscopy on amorphous carbon at temperatures below 300&#176;C. Here we present data from a variety of published sources alongside our own data reviewing the apparent trends in amorphous carbon with some discussion related to thermal regime (intensity, duration), with case studies including intruded host rocks, fold and thrust belts and wildfires. We conclude that Raman spectroscopy can be applied successfully to &#8216;low-temperature&#8217; carbonaceous material whilst noting the challenges faced to fully understand the physio-chemical mechanisms at these temperature ranges.</p>

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