IONIC LIQUID–LIQUID PHASE MICROEXTRACTION FOR THE SENSITIVE DETERMINATION OF SANGUINARINE AND CHELERYTHRINE IN CHINESE HERBAL MEDICINES AND HUMAN URINE

In the current paper, an efficient in situ solvent formation microextraction (ISFME) combining high performance liquid chromatography with fluorescence detection was developed for the determination of sanguinarine and chelerythrine in Macleaya cordata (Willd.) R. Br. and Chelidonium majus L. The amount of ion-pairing agent (KPF6) was added to the sample solution containing a water-miscible ionic liquid (IL; [C6MIM][Br]) to obtain a hydrophobic ionic liquid ([C6MIM]PF6), which acted as the extraction phase to replace the volatile organic solvent as the extraction solvent. Several important parameters influencing the extraction efficiency of IL-ISFME, such as the type and volume of IL, amount of KPF6, sample pH, extraction time, and centrifugation time, were optimized. Under optimal conditions, sanguinarine and chelerythrine exhibited good linearity, with correlation coefficients of 0.9992 and 0.9993, respectively, linear range of 0.1–200 ng mL−1, and limit of detection of 0.08 ng mL−1. The spiked recovery for each analyte was in the range of 97.8%–102.3%. The experimental results indicate that the proposed method was successfully applied to the analysis of two alkaloids in M. cordata (Willd.) R. Br., C. majus L. and human urine.