Determination of lead in Gentiana rigescens and evaluation of the effect of lead exposure on the liver protection of the natural medicine

In this work, ultrasound-assisted rapidly synergistic cloud point extraction (UARS-CPE) and inductively coupled plasma optical emission spectrometry (ICP-OES) were combined to determine trace Pb in Gentiana rigescens Franch. ex Hemsl. ( G. rigescens ) samples. Under the optimal conditions, the enhancement factor (EF), limit of detection (LOD), limit of quantitation (LOQ) and precision were 33, 0.11 μg L −1 , 0.37 μg L −1 and 1.3%, respectively. This method was applied to the analysis of G. rigescens samples, and the outcomes were in good agreement with the results determined by inductively coupled plasma mass spectrometry (ICP-MS). A mice model of immune liver injury induced by concanavalin A (ConA) was established, and the liver protection of G. rigescens and gentiopicroside (GPS) on it and the effects of various dosages of Pb exposure on its liver protection were studied. Pb at a dosage of 5 mg kg −1  had little effect on the liver protection of G. rigescens and GPS, while 25, 125 mg kg −1 dosages of Pb could significantly attenuate the liver protection of both. In addition, it aggravated the necrosis of hepatocytes and inflammatory cell infiltration , and these effects were dose-dependent.