On-line monitoring of extraction process of Danhong injection based on near-infrared spectroscopy

Abstract

To establish a rapid quantitative analysis method for the quality control of Danhong injection extraction using near-infrared (NIR) spectroscopy. Online collecting the NIR spectra during the mixed extraction process of Salvia miltiorrhiza and Carthamus tinctorius, partial least squares regression (PLSR) models were developed for the quality indicators rosmarinic acid (RA), salvia acid B (SaB), lithospermic acid (LA), hydroxysafflor yellow A (HSYA) and solid content (SSC), with HPLC and weight-loss method as reference methods. The correlation coefficients of the cross validation for RA, SaB, LA, HSYA and SSC were 0.909 3, 0.915 2, 0.901 9, 0.747 7 and 0.931 4, respectively. And the root mean square errors of cross validation (RMSECV) were 0.012 1, 0.251, 0.017 7, 0.038 1 g x L(-1) and 0.359%, respectively. In this study, NIR spectroscopy was successfully applied to achieve the real-time determination of the contents of RA, SaB, LA and SSC, while the performance of the HSYA calibration model needed to be improved.