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. The work effectively combined ultrasound-assisted rapidly synergistic cloud point extraction with inductively coupled plasma optical emission spectrometry to determine trace Pb in Gentiana rigescens samples. And a mice model of immune liver injury induced by concanavalin A was established, and the liver protection of Gentiana rigescens and gentiopicroside on it and the effect of different doses of Pb exposure on its liver protection were studied. [Display omitted] •Trace Pb in the natural medicine G. rigescens was firstly determined by the method.•Effect of lead exposure on the liver protection of G. rigescens was firstly studied.•The protective effect of the natural medicine on immune liver injury was investigated.•UARS-CPE can be achieved at room temperature and feasibly combined with ICP-OES.•Analytical performance of ICP-OES for detection of Pb was significantly improved.