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OBJECTIVE@#To develop a fiber Raman endoscopic probe that can be integrated in a gastroscope and evaluate its value in the diagnosis of gastric cancer.@*METHODS@#The Raman spectra of gastric cancer tissues and normal tissues were obtained using the fiber Raman endoscopic probe and confocal microRaman spectroscopy. After preprocessing with smoothing, baseline elimination and normalization, the spectroscopic data were analyzed by the principle component analyses combined with stechiometry. Based on the pathological results, the diagnostic accuracy, sensitiveness and specificity of Raman spectroscopy combined with stechiometry were evaluated.@*RESULTS@#The fiber Raman endoscopic probe and microRaman spectroscopy revealed significantly different Raman spectra between gastric cancer tissues and normal tissues. The diagnostic accuracy, sensitiveness and specificity of the fiber Raman endoscopic probe was 80.56%, 88.89%, and 84.72% for gastric cancer, respectively.@*CONCLUSIONS@#The fiber Raman endoscopic probe combined with stechiometry provides an effective modality for the diagnosis of gastric cancer and can well distinguish gastric cancer tissue from normal gastric tissues.
Assuntos
Humanos , Endoscopia , Tecnologia de Fibra Óptica , Sensibilidade e Especificidade , Análise Espectral Raman , Neoplasias GástricasRESUMO
Objective:To fast detect hypotensive drugs illegally added to the flower buds of Panax notoginseng. Methods:A laser Raman spectrometer was used to detect several chemical drugs added to the flower buds of Panax notoginseng, and the spectrum was qualitatively analyzed. Results:Raman spectroscopy could detect chemical antihypertensive drugs added to the flower buds of Panax notoginseng, and the test results were in accordance with those of the traditional method. Conclusion: Raman spectroscopy can be used for the determination of illegal additives in the flower buds of Panax notoginseng.
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OBJECTIVE: To analyze the polymorphs of carbamazepin tablets by laser confocal micro-Raman spectrometer and establish the identification test model. METHODS: Reference Raman spectra of the four crystal forms of carbamazepin were established; then the polymorphs of the carbamazepin tablets from different manufacturers were analyzed, and an identification test model was established to distinguish the unknown samples. RESULTS: According to the results of the cluster analysis, the four batches of carbamazepin tablets from domestic manufacturers belonged to crystal form III. A qualitative model was created by choosing the first derivative and vector normalization method to process the spectra, using the factorization method to calculate, and selecting the 200-500, 650-850, 1 000-1 100, 1 500-1 700 cm-1 regions to compare. This model was verified to have high sensitivity, specificity, precisicion, negative prediction ability, and detection efficiency. CONCLUSION: The laser confocal micro-Raman spectrometer canbe used to analyze the polymorphs of carbamazepin tablets and the qualitative identification is rapid and accurate.
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Objective:To develop a method for the rapid determination of CaSO4 ·2H2 O in gypsum by Raman spectra. Methods:Totally 40 batches of gypsum from different origins were used as the training set, compared with the results by ENTA titration, and OPUS software was used to establish a quantitative analysis model of CaSO4 ·2H2 O in gypsum by Raman spectra. Results:The estab-lished quantitative analysis model could provide a good prediction result rapidly when the content was between 97. 93% and 99. 81%. Conclusion:The method is accurate, fast and simple, which can be developed as an analysis method for CaSO4 ·2H2 O in gypsum.
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OBJECTIVE: To establish a Raman spectroscopy method for the determination of tiopronin injection. METHODS: Based on Raman scattering theory, the light intensity of the laser Raman peak is in proportional to the concentration of tiopronin samples in aqueous solution. A quantitative method for determination of tiopronin injection using Raman spectroscopy was established by selecting the Raman peak of tiopronin sulfhydryl group (S-H[2580 cm-1]) as quantitative peak. RESULTS: The calibration curve was linear over the range of 10 - 100 mg · mL-1 (r = 0.9999, n =6), and the average recovery was 101.98% with RSD of 2.09% (n = 9). CONCLUSION: The method is convenient and rapid. It is expected to be used in the quality control of tiopronin injection. Copyright 2012 by the Chinese Pharmaceutical Association.
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Organics of the phthalocyanine category have very good nonlinear optical properties. The single-walled carbon nanotubes were modified by using the phenoxy phthalocyanine. Characterization analysis was made by means of the transmission electron microscope (TEM), ultraviolet visible absorptive spectra, fluorescent spectra and Raman spectra. Under the TEM, it was observed that the composite looked like sugarcoated haws. By comparing the ultraviolet visible absorptive spectra before and after absorption, it was disclosed that the spectral intensity and the intensity of the peaks in the fluorescent spectra dropped remarkably. This shows that the single-walled carbon nanotubes have absorbed a large number of phenoxy phthalocyanines. Raman analysis revealed that in the Raman spectra, the position of the main peaks of the single-walled carbon nanotubes after absorption moved in the direction of long waves. The analysis suggests that the movement of the Raman spectra results from the change in the state of the single-walled carbon nanotubes before and after absorption.
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Organics of the phthalocyanine category have very good nonlinear optical properties. The single-walled carbon nanotubes were modified by using the phenoxy phthalocyanine. Characterization analysis was made by means of the transmission electron microscope (TEM), ultraviolet visible absorptive spectra, fluorescent spectra and Raman spectra. Under the TEM, it was observed that the composite looked like sugarcoated haws. By comparing the ultraviolet visible absorptive spectra before and after absorption, it was disclosed that the spectral intensity and the intensity of the peaks in the fluorescent spectra dropped remarkably. This shows that the single-walled carbon nanotubes have absorbed a large number of phenoxy phthalocyanines. Raman analysis revealed that in the Raman spectra, the position of the main peaks of the single-walled carbon nanotubes after absorption moved in the direction of long waves. The analysis suggests that the movement of the Raman spectra results from the change in the state of the single-walled carbon nanotubes before and after absorption.