Biological Applications of Attenuated Total Reflection (ATR) Spectroscopy
The use of infrared spectroscopy for the study of biological systems and species has been slowly increasing for the past decade and has been accelerating in the last several years. This growth in biological IR can easily be demonstrated by the increase in the number of biological IR papers presented at various meetings. Biological molecules, such as proteins, are natural polymers, but unlike synthetic polymers, biological polymers do not have a true repeat unit. This makes the theoretical treatment and the understanding of the biological spectrum more complicated. The spectral changes accompanying these structural changes can then be used to interpret the spectra in terms of the original biological structure. This chapter describes some of the experimental techniques and protocols used in biological attenuated total reflection (ATR) studies and give selective overview of some of the applications of ATR in biology.