Raman spectroscopy has generated many branches during the development for more than 90 years. Surface enhanced Raman spectroscopy (SERS) improves SNR by using the interaction between tested materials and the surface of rough metal, as to quickly get higher sensitivity and precision spectroscopy without sample pretreatment. This article describes the characteristic and classification of SERS, and updates the theory and clinical application of SERS. It also summarizes the present status and progress of SERS in various disciplines and illustrates the necessity and urgency of its research, which provides rationale for the application for SERS in microbiology.
Microbiology ; Spectrum Analysis, Raman

PURPOSE: The purpose of the present study was to evaluate the effect of thermocycling and mechanical loading on the biaxial flexural strength and the phase transformation of one Ce-TZP/Al2O3 and two Y-TZP core materials. MATERIALS AND METHODS: Thirty disc-shaped specimens were obtained from each material. The specimens were randomly divided into three groups (control, thermocycled, and mechanically loaded). Thermocycling was subjected in distilled water for 10000 cycles. Mechanical loading was subjected with 200 N loads at a frequency of 2 Hz for 100000 times. The mean biaxial flexural strength and phase transformation of the specimens were tested. The Weibull modulus, characteristic strength, 10%, 5% and 1% probabilities of failure were calculated using the biaxial flexural strength data. RESULTS: The characteristic strengths of Ce-TZP/Al2O3 specimens were significantly higher in all groups compared with the other tested materials (P<.001). Statistical results of X-ray diffraction showed that thermocycling and mechanical loading did not affect the monoclinic phase content of the materials. According to Raman spectroscopy results, at the same point and the same material, mechanical loading significantly affected the phase fraction of all materials (P<.05). CONCLUSION: It was concluded that thermocycling and mechanical loading did not show negative effect on the mean biaxial strength of the tested materials.
Spectrum Analysis, Raman ; Water ; X-Ray Diffraction

Oral cancer is a common and deadly malignancy.While multidisciplinary treatment(mainly surgery)has been applied in the treatment of cancer treatment,early diagnosis and complete removal of the primary lesion are essential for a better prognosis.Raman spectroscopy is an optical technique that detects inelastic scattered light generated by the interaction of light and matter.It can detect the vibrational spectra of biochemical and biomolecular structures and tissue conformations,and can provide the "molecular fingerprint" for cells,tissues,and biological fluids.With the development of related technologies and optical instruments,Raman spectroscopy has been widely applied in medical fields.This article reviews the research advances and application of Raman spectroscopy in the diagnosis of oral cancer.
Humans ; Mouth Neoplasms ; Spectrum Analysis, Raman

BACKGROUND: The purpose of this study is to investigate differences of chemical composition between subchondral bone in advanced osteoarthritic (OA) and non-OA distal femur. METHODS: Twenty femurs were harvested, respectively. The subchondral trabeculae were obtained from the middle of medial articular surface of distal femurs. A 10 mm diameter cylindrical saw was used to harvest. Raman spectroscopy, a non-destructive technique, was employed to determine the chemical information of the trabecular bones in the human distal femurs. RESULTS: The maximum intensity of the phosphate peak was 2,376.51+/-954.6 for the non-OA group and 1,936.3+/-831.75 for the OA group. The maximum intensity of the phosphate peak observed between the two groups was significantly different (P=0.017). The maximum intensity of the amide I peak were 474.17+/-253.42 for the nonOA group and 261.91+/-205.61 for the OA group. The maximum intensity of the amide I peak were significantly different between the two groups (P=0.042). Also, among other chemical and matrix components (Hydroxyproline,Carbonate, Amide IIIdisordered;ordered, and CH2), the spectrums showed similar significant differences in the intensity (P=0.027, P=0.014, P=0.012; P=0.038, P=0.029). Area integration were performed to determine disorder in collagen's secondary structure via amide III (alpha helix/random coil). The value of the alpha helix to random coil band area are significantly different (P=0.021) and result showing that there was a trend toward higher collagen maturity for the nonosteoarthritic bone specimens. CONCLUSIONS: The result suggested that OA may affect the chemical compositions of trabecular bone, and such distinctive chemical information may be.
Cartilage ; Collagen ; Femur ; Humans ; Osteoarthritis* ; Spectrum Analysis, Raman

Raman spectroscopy is an optical technology based on the theory of Raman scattering, which is generally used in the research of medical and biological science. Raman spectroscopy can be used to detect the molecular structures and components of proteins, lipids, DNA, and other biological molecules, and provide substantial information about molecules. Thus, Raman spectroscopy is generally considered a "molecular fingerprint", and it has exceptional advantages in medical research. Moreover, this technique can reflect the changes in molecular structures and detect the alterations of chemical constituents in the samples. Raman spectroscopy, given its high sensitivity and specificity in the detection of the biological samples, has been successfully used to detect and diagnose diseases in numerous sites, such as skin, oral mucosa, breast, head, and neck. In this paper, we introduce the application of Raman spectroscopy in stomatology by conducting a review of the literature.
DNA ; Lipids ; Oral Medicine ; Proteins ; Sensitivity and Specificity ; Spectrum Analysis, Raman

OBJECTIVES: The purpose of this study is to evaluate bonding efficacy by means of measuring the effect of remained solvent on Degree of conversion(DC) and microTBS and FE-SEM examination. MATERIALS AND METHODS: Two 2-step total etching adhesives and two single-step self etching adhesives were used in this study. First, volume weight loss of 4 dentin adhesives were measured using weighting machine in process of time in normal conditions and calculate degree of evaporation (DE). Reaction/reference intensity ratio were measured using micro-Raman spectroscopy and calculate DC according to DE. Then 2 experimental groups were prepared according to air-drying methods (under, over) and control group was prepared to manufacturer's instruction. Total 12 groups were evaluated by means of micro tensile bond strength and FE-SEM examination. RESULTS: Degree of evaporation (DE) was increased as time elapsed but different features were observed according to the kind of solvents. Acetone based adhesive showed higher DE than ethanol and butanol based adhesive. Degree of conversion (DC) was increased according to DE except for S3 bond. In microTBS evaluation, bond strength was increased by additional air-drying. Large gaps and droplets were observed in acetone based adhesives by FE-SEM pictures. CONCLUSIONS: Additional air-drying is recommended for single-step self etching adhesive but careful consideration is required for 2-step total etching adhesive because of oxygen inhibition layer. Evaporation method is carefully chose and applied according to the solvent type.
Acetone ; Adhesives ; Dentin ; Ethanol ; Oxygen ; Solvents ; Spectrum Analysis ; Spectrum Analysis, Raman ; Weight Loss

Drug Contamination ; Drugs, Chinese Herbal ; analysis ; Fourier Analysis ; Plants, Medicinal ; chemistry ; Spectrum Analysis, Raman ; instrumentation ; methods

Based on Ag nanoparticles as the surface-enhanced Raman spectroscopy (SERS)-active nanostructure, the SERS of uric acid was presented in the paper. The absorption spectroscopies of uric acid and the mixture of silver colloids and uric acid were measured. The possible enhancing mechanism of the uric acid on silver colloid was speculated. The characteristic SERS bands of uric acid were tentatively assigned. The influence of absorption time and different ion on the SERS of uric acid were also discussed. The SERS spectral intensity changes linearly with the uric acid concentration, which indicated that the SERS might provide a new kind of direct and fast detecting method for the detection of uric acid. The detection limit of uric acid in silver sol is found to be 1 mg/L.
Metal Nanoparticles ; chemistry ; Silver ; chemistry ; Spectrum Analysis, Raman ; methods ; Surface Properties ; Uric Acid ; analysis

Chinese medicinal material is the foundation of traditional Chinese medicine(TCM) industry. Its quality is not only closely related to the health of residents but also the key to the development of the TCM industry. Pesticide residues, heavy metals and mycotoxins are the major pollutants of Chinese medicinal materials. In recent years, quite a number of rapid detection methods for pollutants have been constructed. Among them, surface-enhanced Raman scattering(SERS), which has been widely used in food chemistry, environmental analysis, and other fields because of its speediness and non-destructiveness, shows its great potential in the pollutant detection in Chinese medicinal material. This paper firstly reviews the application of SERS for the detection of common pollutants in Chinese medicinal material. We then discussed the characteristics and advantages of SERS technique for pesticide detection, including the principle, SERS substrate design, specific recognition, etc. Finally, simultaneous detection of multiple pesticide residues in Chinese medicinal material was explored.
China ; Environmental Pollutants ; Medicine, Chinese Traditional ; Pesticide Residues/analysis* ; Spectrum Analysis, Raman

PURPOSE: Raman spectroscopy is a vibrational spectroscopic technique, which is capable of providing details on the chemical composition, molecular structure and molecular interactions in cells and tissues. The primary objective of this study was to explore Raman spectroscopy for the detection of spectral changes between normal and cancer tissue in the stomach. METHODS: Tissue specimens were obtained from the resected stomach of advanced gastric cancer patients. The normal gastric and cancer tissues were harvested from the middle, lower portion of the stomach and from the tumor mass, respectively. 19 sets (antrum, body and cancer) of spectral data, with clearly defined histopathological findings, were selected in this study. FT-Raman spectroscopy (Bruker Inc., Karsruhe, Germany) was used for tissue Raman studies, with excitation at 1, 064 nm. The Raman spectra from the gastric tissue specimens were obtained with a 20 minute signal acquisition time. RESULTS: In the range 700~1, 900 cm-1, the Raman spectra of gastric antral tissue were dominated by a number of vibrational modes of biomolecules, such as proteins, lipids and nucleic acids. The Raman spectrum pattern of gastric body tissue was similar to that of the antrum, suggesting the structure and composition between the gastric antrum and body are much the same. The Raman spectra differed significantly between the normal and malignant cancer tissues, with cancers showing higher percentage signals for protein, lipid and nucleic acid compared to normal tissue (P<0.05). Difference were observed in the shapes of the Raman spectra between the normal and cancer tissues, particularly in the spectral ranges 1, 250~1, 255, 1, 330~1, 340 and 1, 440~1, 450 cm-1, which contain signals relating to protein and lipid conformations and CH2 bending mode of nucleic acids. CONCLUSION: This study demonstrates the ability of Raman spectroscopy to detect biochemical changes in malignant gastric tissue, and may become a useful adjunct to pathological diagnosis allowing guided biopsies and assessment of adequacy of resection margins.
Biopsy ; Diagnosis ; Humans ; Molecular Structure ; Nucleic Acids ; Pyloric Antrum ; Spectrum Analysis ; Spectrum Analysis, Raman* ; Stomach Neoplasms ; Stomach*