Efficiency of the Fourier Transform infrared method in identifying terahertz spectral features of vitamins in low concentrated samples

The terahertz spectra of low concentrated forms of vitamin C, vitamin B6 and vitamin B3 were measured using Fourier Transform infrared spectroscopy. The measured spectra were characterized by distinct broad absorption bands in the considered frequency range. Each vitamin showed a unique spectral profile highlighting the use of Fourier Transform infrared spectroscopy in the low frequency characterization of these materials. A comparison made between the experiment and related study performed using the Terahertz time domain spectroscopy revealed a very good correspondence in the observed frequencies. There were minor variations of less than 0. 5 THz between the experimental frequencies and the literature values. This study highlights the capability of the Fourier Transform infrared technique in terahertz characterization of low concentrated materials despite its limited use in considered region.