Three‐phase hollow‐fiber liquid‐phase microextraction based on deep eutectic solvent as acceptor phase for extraction and preconcentration of main active compounds in a traditional Chinese medicinal formula

Abstract

A three-phase hollow-fiber liquid-phase microextraction based on deep eutectic solvent as acceptor phase was developed and coupled with high-performance capillary electrophoresis for the simultaneous extraction, enrichment, and determination of main active compounds (hesperidin, honokiol, shikonin, magnolol, emodin, and β,β ′dimethylacrylshikonin) in a traditional Chinese medicinal formula. In this procedure, two hollow fibers, impregnated with n-heptanol/n-nonanol (7:3, v/v) mixture in wall pores as the extraction phase and a combination (9:1, v/v) of methyltrioctylammonium chloride/glycerol (1:3, n/n) and methanol in lumen as the acceptor phase, were immersed in the aqueous sample phase. The target analytes in the sample solution were first extracted through the organic phase, and further back-extracted to the acceptor phase during the stirring process. Important extraction parameters such as types and composition of extraction solvent and deep eutectic solvent, sample phase pH, stirring rate, and extraction time were investigated and optimized. Under the optimal conditions, detection limits were 0.3-0.8 ng/mL with enrichment factors of 6-114 for the analytes and linearities of 0.001-13 μg/mL (r 2 ≥ 0.9901). The developed method was successfully applied to the simultaneous extraction and concentration of the main active compounds in a formula of Zi-Cao-Cheng-Qi decoction with the major advantages of convenience, effectiveness, and environmentally friendliness. K E Y W O R D Sdeep eutectic solvents, high performance liquid chromatography, hollow-fiber liquid-phase microextraction, traditional Chinese medicine Article Related Abbreviations: 2p-HF-LPME, two-phase hollow-fiber liquid-phase microextraction; 3p-HF-LPME, three-phase hollow-fiber liquid-phase

Application of solidified floating double-solvent dispersive liquid-phase microextraction for the analysis of the main active components in Zicao Chengqi decoction

“…To further clarify the feasibility of SF-DS-DLPME, we compared it with the other related analysis methods reported [32] (Table 3). As can be seen from Table 3, the EFs of analytes in SF-DS-DLPME are 3-14 times higher than those of the other methods; the extraction time is shortened by 15 min on average.…”

Microextraction Techniques with Deep Eutectic Solvents

“…The method was successfully applied to dry powder of four medicinal herbs for the determination of their active compounds such as hesperidin, honokiol, shikonin etc. The detection limits of the proposed method were 0.3-0.8 ng/mL, while the higher extraction efficiency and absence of salt were considered as advantages in comparison with 2p-HF-LPME [90]. On the other hand, in Zhang's report, a tetrabutylammonium chloride (TBAC)-hexanoic acid (HA) DES with 1:3 molar ratio was utilized to impregnate the porous as extraction phase and 85% DES in methanol to fill the lumen of hollow fiber as an acceptor phase.…”

Recent advances of green pretreatment techniques for quality control of natural products

“…This three-phase HF-LPME could obtained great extraction and enrichment efficiency for the targets. Xue et al applied three-phase HF-LPME to extract and preconcentrate main active ingredients in a TCM formula, which is based on n-heptanol/n-nonanol (7:3, v/v) to form a SLM in the wall pores and DES as acceptor phase [64]. Liu et al proposed a three-phase HF-LPME technique based on reverse micelle for the determination of four kinds of cinnamic acids in TCM [65].…”