Monitoring of the hydrolysis process of bear bile powder using near infrared spectroscopy and chemometrics

A near infrared (NIR) spectroscopy-based method was developed for monitoring the hydrolysis process of bear bile powder. During the hydrolysis process, samples were collected and measured using both NIR spectrometer and high performance liquid chromatography. The quantitative calibration models were established with the collected NIR spectra and the reference concentrations of tauroursodeoxycholic acid (TUDCA), taurochenodeoxycholic acid (TCDCA), ursodeoxycholic acid (UDCA), and chenodeoxycholic acid (CDCA) using partial least squares regression algorithm. After the models were established and validated, the samples of new batches can be determined rapidly, and the hydrolysis process of bear bile powder can be monitored quantitatively. Additionally, a moving block of standard deviation (MBSD) method was also developed for the endpoint determination of the hydrolysis process. The proposed methods have reduced the laborious workload of process sample analysis significantly, and the fast analytical results have contributed to the understanding and controlling of the bear bile powder hydrolysis process.