Role of Raman spectroscopy in bio and agriculture as an optical diagnostic tool

Abstract

Raman spectroscopy proved itself a powerful, label free, nondestructive fingerprint tool for tissue characterization and disease reorganization. Raman spectroscopy has been employed for identifying the biochemical changes associated with the infection in human blood sera, in an effort to establish the Raman spectral marker which could be used for the optical diagnostic purposes. In our group at NILOP, we have successfully employed Raman spectroscopy for the diagnosis of Dengue and HCV virus infection. We have also applied this technique for Malaria, and breast cancer in blood sera using laser at 785nm and 532nm as an excitation source. We have also used this technique for characterization of saturated and unsaturated fats in the edible oils, spreads and ghee using 785nm laser as an excitation source. Analysis of Raman spectra in case of Dengue and malaria showed that straight forward spectral lines can be used to characterize the infected blood sera. Analysis of Raman spectra in case of HCV, Breast cancer, edible oils, spreads and ghee showed that straight forward spectral lines cannot be used for characterizing the infected blood sera, not to be used for characterizing the infected blood sera, therefore a multivariate analysis code has been developed, which was based on the partial least square (PLS) regression and Principal component analysis (PCA) for the optical diagnosis of infection in human blood sera. In addition, we have employed Raman spectroscopy with multivariate model for the quality assurance of edible oils, spreads and ghee. The results are very much encouraging and useful for clinical implementation. The Raman spectroscopic as an optical diagnostic technique is very much cost effective as compare to conventional methods. Running cost is just a glass slide and results are online.