A Membrane Method for Terahertz Spectroscopy of Amino Acids

We present here the results of applying a membrane method to terahertz (THz) transmittance spectroscopy of amino acids. Two kinds of amino acids dissolved in water or bovine serum were dropped and dried on polymer membranes. Absorbance spectra of the membranes were obtained with a GaP THz spectrometer. The frequency range was 0.6 - 6.0 THz and the line width was 3 GHz. Characteristic absorption peaks attributable to the amino acids were observed with membranes made of suitable materials.