[Fast analytical method on content and transfer rate of marker component in ethanol precipitation of cinobufacini by near infrared spectroscopy].

The method of near infrared spectroscopy was established to analyze the content and transfer rate of the marker component, indole alkaloids, of cinobufacini in the process of ethanol precipitation. The samples of cinobufacini were collected, and the concentration of indole alkaloids was determined by the reference method, UV-vis spectroscopy. After the rejection of abnormal samples, the pretreatment of spectra and the choice of the corresponding wave band, the multivariate calibration models were established using PLS algorithm between spectra and the UV values. The samples in ethanol precipitation, which did not participate in modeling, were used to examine the performance of the models. The correlation coefficient of the calibration model was 0.9613. Root mean square error of calibration (RMSEC) and root mean square error of prediction (RMSEP) were 0.172 and 0.169, respectively. Furthermore, residual predictive deviation (RPD) of the model was 4.13, which meant quantity analysis was feasible. It is concluded that near infrared spectroscopy can be considered as a fast, effective and non-destructive analysis method applied in the process of ethanol precipitation for traditional Chinese medicine.