**10. Conclusion**

306 Infrared Spectroscopy – Life and Biomedical Sciences

inserted to obtain spectra of the surface layers. Studies pertaining to these objectives have utilized fiber-optic sensors for diagnosis of malignancies (Li et al 2005, Katkuri et al 2010) and under conditions of aqueous interference (Bindig et al 2003). Presently malignant tissues are excised during colonoscopy and send for evaluation. With the development of suitable probes, it is envisoned that other than the area with the symptoms, adjoining areas can be evaluated to determine the extent of spread of disease and redefine the resection margin. Another potential use would be to differentiate diseases with similar symptoms like IBD and cancer using such probes. This would help in early intervention and prevent recurrent surgeries resulting in less patient discomfort and less expenses. Thus, the field of FTIR based disease diagnosis can be utilized in various levels such as the simple diagnosis using IR

The diagnostic potential of FTIR spectroscopy relies upon its ability to detect and monitor changes in the biochemical fingerprint of abnormal cells, tissues and molecules as compared to the normal conditions along with its ability to monitor minute spectral differences among closely related samples. Thus, establishing reference set of spectra of every biological entity that is being studied is an integral part as with other spectroscopic methods, often the references data base built using model compounds, whose exact spectral contribution is known (Benedetti et al 1996). Biological samples are procured after many different types of procedures and thus, each type may demand different approach for spectral acquisition and analysis. In addition, the availability of the instrument set up and resources would play an important role in deciding which types of samples can be analyzed in a particular clinical set up. For example, when both FTIR microscopy and normal spectroscopy is available, blood components can be examined by the normal method while tissues and biopsies can utilize the microscopy. Similarly, the tissue architect dictates the type of measurement to be followed. While tissues like cervical epithelium where distinct zones permit the spectral acquisition at several locations within a uniform region (Figure 3) more complex tissues like melanoma and nevus make it imperative that the location is carefully selected to not exclude desired region and not include regions that do not meet the criterion of either normal or diseased conditions (Hammody et al 2005). Complicated tissues like colonic epithelium present two possibilities of data acquisition, along the cross section (Argov et al 2002,2004) or longitudinal section (Sahu et al 2004b, 2010) of the crypts and inevitably the availability of microscopic or FPA facilities. Understanding the spectral differences due to instrumentation has been undertaken with the objective of tailoring the techniques to suit set ups and also verifying the universal applicability of certain parameters compared to others (Hammody et

The biogenesis of each cell or tissue needs to be studied before a suitable methodology is designed to obtain spectral data for the specific purpose it is intended to serve. The various protocols are also required to be suitably modified depending upon whether a sample is fresh, frozen or paraffin embedded to exclude interfering substances (Sahu et al 2005). The spectroscopy of microorganisms on the other hand may be simpler (Sahu et al 2006b).Both FTIR and Raman spectroscopy use vibrational spectroscopy and can be used independently or in combination with each other as a means of spectroscopic evaluation of biological samples(Mourant et al 2003b, Krishna et al 2005, Oust et al 2006). The prospective of

microscopes to advanced in-vivo methods using fiberoptic sensors.

**9. Discussion** 

al 2007).

The technique of FTIR spectroscopy is now being used for different purposes like identification of organisms and their classification, determination of status of tissues, monitoring the effects of drugs on cell lines, monitoring treatment regimen and studying interactions between biological systems in the arena of biomedical research. Owing to its simplicity of data acquisition compared to more sophisticated methods like NMR and development of computational methods for rapid data processing, its relevance in biomedical research is bound to increase over the coming years, in spite of the initial block of having large amounts of spectra for analyses.
