Rapid Prediction of Emodin in Danning Tablet Intermediate by Model Established by Near Infrared Spectroscopy with Partial Least Square Method

In order to improve the detection efficiency, a quantitative analysis model for rapid prediction of emodin in Danning tablet intermediate was established by near infrared spectroscopy with partial least square method (PLS). The original near infrared spectra of 136 batches of training set samples were collected by near infrared spectrometer, and the original near infrared spectra data were pretreated by standard normal variate (SNV) and second derivative (2^nd), and the quantitative analysis model of emodin was established by PLS in the wavelength ranges of 1 300-1 764 nm and 1 932-2 200 nm. It was shown that the determination coefficient (R²) of the model was 0.770 8 and the root mean square error of cross validation (RMSECV) was 0.086 2. The 199 batches of testing set samples were used for verification. The results showed that the relative mean deviation absolute values of the predicted values obtained from the model analysis and the reference values obtained from the high performance liquid chromatography analysis were less than 5.0%, indicating that the prediction accuracy of the model was high.