Near‐infrared Raman spectroscopy for optical diagnosis of lung cancer

Abstract

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

Raman spectroscopy can differentiate malignant tumors from normal breast tissue and detect early neoplastic changes in a mouse model

“…8,11,[34][35][36][37][38][39][40][41][42][43][44] Our data is confirmatory, and, in addition, demonstrates changes in the tumor bed, which probably represent the detection of chemical signs of preneoplastic changes.…”

“…Thus, Raman spectroscopy is likely to be a useful technique. [1][2][3][4][5][6][7][8][9][10][11] The objectives of this study were to evaluate the sensitivity and specificity of Raman spectroscopy in differentiating between cancer and normal breast tissue in a mouse model.…”

Characterization and Visualization of Vesicles in the Endo-Lysosomal Pathway with Surface-Enhanced Raman Spectroscopy and Chemometrics

“…42 The breakdown of lipids affects the structural conformation of the lipid backbone and the decrease of the band around 1440 -1460 cm -1 (y2) in lysosomes supports this assertion, as this region is assigned to the scissoring and rocking vibrations of CH 2 and stretching vibration of CH 3 . 47,57 Changes in SERS in endosomes and lysosomes related to pH…”

Vibrational spectroscopic studies of newly developed synthetic biopolymers

“…Raman spectra can also unravel a ''fingerprint region'' of specific molecular species, and can therefore be potentially used for biomedical applications. 25 The Raman spectra of lipids are dominated by the vibrational modes originating from CÀ ÀC and CÀ ÀH stretching regions. As a representative result, Raman spectrum (1-min integration time) and peak assignments of pure GDM-12 lipid sample for two spectral regions, 1800-1000 cm 21 and 3000-2800 cm 21 , are exhibited in Figure 5.…”

“…22,23 This approach has been widely practiced to optically detect the biochemical changes of biological sample such as stem cells, tumor tissue, blood cells, bacteria, DNA, RNA, proteins, viruses etc. 21,24,25 Recently, an interesting application of FTIR spectroscopy for the diagnosis of cell death has been reported. 26 More importantly, these techniques have been extremely useful for the characterization of thermal properties of lipids and lipid vesicles in suspension specifically by analyzing the changes in the intensity ratios and shift in the band positions of Raman and infrared spectra as a function of temperature.…”