Quantitative analysis of amino acids based on THz refractive index spectra

摘要

The qualitative and quantitative analysis of amino acids by terahertz (THz) refractive index spectra is discussed. The frequency band of anomalous dispersion emerging in the spectra is unique for the amino acids, L-glutamine (Gln) and L-histidine (His). The refractive indices of the amino acids were found to be linearly proportional to the concentrations. The calibration models were established to determine concentrations of Gln and His mixture samples by partial least square (PLS) regression method.