Quantification of eight active ingredients in crude and processed radix polygoni multiflori applying miniaturized...

A rapid, efficient, and green sample preparation method has been developed to extract eight active ingredients (gallic acid, catechins, epicatechin, polydatin, 2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glucoside, resveratrol, emodin, and physcion) in radix polygoni multiflori by miniaturized matrix solid-phase dispersion microextraction. Simple and sensitive ultra high performance liquid chromatography combined with ultraviolet detection has been applied to analyze the multiple compounds. The best results were obtained by adding 25 mg sample into 25 mg adsorbent and grinding for 2 min with disorganized silica as adsorbent and 1 mL 150 mM 1-dodecyl-3-methylimidazolium bromide as a green eluting solvent. Good linearity (r²  > 0.998) for each analyte was obtained by this method. The intra-day and inter-day precision (RSD) were both below 5.31%, and the recoveries of the analytes ranged from 93.3 to 100.0%. This simple miniaturized matrix solid-phase dispersion microextraction method for analyzing the compounds in radix polygoni multiflori needs a short time and requires little sample and reagent. Thus, this method is far more eco-friendly and efficient than traditional extraction methods (reflux and ultrasound-assisted extraction). The present investigation provided a promising method for the fast preparation and discrimination of chemical differences in crude and processed radix polygoni multiflori.