Infrared Emission Spectroscopy for Investigation of Biological Molecules in Aqueous Solutions

Abstract

Abstract: Examples are given of using infrared emission spectroscopy to analyze the structure of biological molecules in aqueous solutions. Instead of sample heating commonly used in emission spectroscopy, it is proposed to use a cold background for screening environmental thermal emission. Emission spectra are measured for three types of molecular biological objects in aqueous solutions: protein (bovine serum albumin 1 mg/mL in H2O), phospholipid (1,2-dimiristoylphosphatidylcholine 1 mg/mL in D2O) in two phase states (gel at 10°С and liquid crystal at 35°С), and nucleotide (adenosine-5'-triphosphate 1 mg/mL in H2O). Characteristic bands are obtained for each of the samples. Higher sensitivity and wider application of infrared emission spectroscopy with a cold background in comparison to that with sample heating are discussed.