On-line monitoring of traditional Chinese medicinal powder blending process by using near-infrared spectroscopy / 中国药学杂志

ABSTRACT

OBJECTIVE: To establish a rapid method based on near-infrared diffuse reflectance spectroscopy (NIR) to monitor the blending process of traditional Chinese medicinal powder on-line. METHODS: NIR spectra were collected during the blending processes of mixtures consisting of Red Peony Root powder and defatted Spine Date Seed powder. Multivariate calibration models based on PLS regression were developed to correlate the collected spectra with the content of Red Peony Root powder. The optimal calibration model was applied to monitor the blending process in real time with noninterference. RESULTS: After spectral pretreatment using multiplicative signal correction (MSC), first derivative and Savitzky-Golay filter, Red Peony Root powder contents were quantified using PLS algorithm in the spectral ranges of 5900-5950 cm-1, 6700-6750 cm-1 and 6950-7100 cm-1. The correlation coefficient of the calibration model was 0.9990. The RMSEC, RMSEP and RMSECV were 1.14, 1.16 and 1.26, respectively. CONCLUSION: It was demonstrated that a miniature near-infrared analyzer could be used to monitor the contents of the constituents and the blending homogeneity of traditional Chinese medicinal powder in real time, and to rapidly determine the end-point of blending process. In addition, it can be used to judge whether the physical state of powder mixture conforms to the standard. Therefore, NIR spectroscopy is considered to be an appropriate PAT tool for end-point control of blending process of traditional Chinese medicinal powder.