Preliminary study on compound banlangen granules based on terahertz time-domain spectroscopy

The fingerprint technology of traditional Chinese medicine is a more effective method to ensure the quality stability of traditional Chinese medicine and control the quality of traditional Chinese medicine. As the core of fingerprint technology of traditional Chinese medicine, terahertz time-domain spectroscopy (THz-TDS) is very suitable for the detection of traditional Chinese medicine. In this paper, a free-space transmission terahertz time-domain spectroscopy system developed by us was used to detect the compound banlangen tablets. The absorption spectra and refractive index spectra of the compound banlangen tablets with different thicknesses, manufacturers and batches were studied. The results showed that: the difference in thickness, batch and manufacturer didn’t affect the terahertz characteristic absorption peak position of compound banlangen tablet, and there were two obvious absorption peaks (1.10THz, 1.17THz) in the tablets; the increase of the thickness caused the absorption peak of the tablet to become smaller and even disappear, and the refractive indexes of tablets with different thicknesses were also quite different; The absorption peaks of tablets with different batches were roughly the same, and the refractive indexes were slightly different; The absorption peaks and refractive indexes of tablets from different manufacturers were basically the same. The above work will help to improve the terahertz fingerprint of compound banlangen, and provide detection means and reference for enriching the quality standard of traditional Chinese medicine.