There are two main types of Ramon spectrometer namely the dispersive and the Fourier Transform (FT) types (Henson & Lowry, 2006). The best one to use depends upon what samples need to be analyzed.
Raman spectroscopy is being used in numerous fields including the pharmaceutical, the carbon and diamond industry, material science, gemology, geology and mineralogy and in forensic science (http://www.renishaw.com/en/raman-spectroscopy-applications--6259 accessed at 13:45 on 28/4/2010). It is so widely used that it even has a journal called the ‘Journal of Raman spectroscopy dedicated to articles relating to the use of this technique (http://www3.interscience.wiley.com/journal/3420/home accessed at 7:02 on 28/4/2010). In this essay, the focus will be on the pharmaceutical industry. Raman spectroscopy is used in drug design, development, formulation and in the manufacture chain. However, the focus as of now will be on how Raman spectroscopy aids in drug development. Numerous examples will be provided to illustrate cases where this technique was used effectively in the development of various drugs.
One of the main applications of Raman spectroscopy in the development of drugs is in the analysis of polymorphs (Henson & Lowry, 2006). Polymorphs are compounds that exist in more than one crystalline form and can be differentiated based on dissimilarities in their physical and chemical properties (Henson & Lowry, 2006). Maintaining control of the polymorphic stage of a compound is essential to development of drugs due to the differences in the different states (Hassan et al, 2008). A good example of this is in the case of a drug called Salmeterol Xinofoate which is used in the treatment of obstructive airway diseases. This drug exists in two forms, I and II of which I is stable and II is not as stable. The commercial drug which is