New oil-in-salt liquid-phase microextraction on permutite for the extraction and concentration of alkaloids inCoptis chinensis

Abstract

A novel oil-in-salt liquid-phase microextraction was developed and introduced for the extraction and concentration of the trace levels of active alkaloids in Coptis chinensis prior to being analyzed by high-performance liquid chromatography with ultraviolet detection. Also, the oil-in-salt extraction mechanism was analyzed, the enrichment factor and extraction recovery were redefined, and the proposed method was compared with other methods. In the approach, the mixed solvent of pentanol/octanol (6:4, v/v) and NaCl (20% w/v) are immobilized on the permutite surface in turn to form oil-in-salt double membranes, through which the target analytes can be molecularized though salting-out effect and be extracted by organic solvent. The main parameters affecting the approach were investigated and optimized. Under the optimized conditions, the enrichment factors of the analytes were 30-117, the linear ranges were 0.002-2 μg/mL for jatrorrhizine, coptisine, and palmatine, and 0.001-3 μg/mL for berberine (r ≥ 0.9923). The limits of detection were less than 1 ng/mL. Satisfactory recoveries (84.3%-120.3%) and precision (0.9%-7.5%) were also obtained. These results confirm that the approach is a simple and reliable sample pretreatment procedure and allows for the quantification of active alkaloids in C. chinensis at actual concentration levels.

Salt‐assisted dispersive liquid–liquid microextraction for enhancing the concentration of matrine alkaloids in traditional Chinese medicine and its preparations

“…Bazregar introduced a centrifugeless DLLME method based upon the salting‐out phenomenon to accelerate the extraction of banned Sudan dyes from food stuff and water samples. Recently, Gao proposed an oil‐in‐salt LPME on permutite, with HPLC, for the enrichment and determination of alkaloids in Coptis chinensis . Soon afterwards, Li developed a novel oil‐in‐salt hollow fiber LPME with HPLC method and introduced it for simultaneous extraction and determination of main active compounds in Zi‐Cao‐Cheng‐Qi Decoction.…”

Sodium dodecyl sulfate sensitized switchable solvent liquid‐phase microextraction for the preconcentration of protoberberine alkaloids in Rhizoma coptidis

“…The primary active ingredients of R. coptidis are quaternary ammonium protoberberine alkaloids, such as berberine, palmatine, coptisine, epiberberine, and jatrorrhizine, which exert detoxifing , anti‐inflammatory, antibacterial , antioxidant , anti‐diarrhea, anti‐diabetes , and antitumor effects. Based on the considerable biological activities and variable concentrations, these alkaloids commonly are characteristic markers for the QC of R. coptidis . In view of their contents varying significantly in different herbs as well as the complexity of matrix, it is essential to develop an efficient sample‐preparation procedure to concentrate and separate the target alkaloids from real complex sample and improve detection sensitivity of the alkaloids before usual instrumental analysis.…”

“…LPME mainly includes three operation modes : dispersive LPME, hollow fiber LPME, and single drop LPME. These LPMEs have been widely applied in many fields such as food control , environmental monitoring , pharmaceutical analysis , and detection of herbal medicines . So far, oil‐in‐salt LPME , hollow fiber double‐solvent synergistic microextraction , and pH‐resolved filter membrane microextraction have been used to extract and enrich the active alkaloids in R. coptidis before analysis.…”

Development of a novel hollow-fiber liquid-phase microextraction based on oil-in-salt and its comparison with conventional one

“…Recently, Gao et al. proposed an oil‐in‐salt liquid‐phase microextraction (LPME) on permutite and introduced it, with HPLC, for the enrichment and determination of alkaloids in Coptis chinensis . However, in the oil‐in‐salt microextraction on permutite, the accepter phase is direct contact with the sample phase, which can cause the target analytes being polluted more or less, and their precisions limited.…”

“…Farajzadeh et al [19] developed a dispersive liquid-liquid microextraction with a new sequence of steps from the view of salt addition to extract and preconcentrate some organophosphorous pesticides from aqueous samples before analysis by GC, in which the authors thought that salt effect is more effective when salt is added into the sample solution after dispersion of extraction solvent than before. Recently, Gao et al [20] proposed an oil-insalt liquid-phase microextraction (LPME) on permutite and introduced it, with HPLC, for the enrichment and determination of alkaloids in Coptis chinensis. However, in the oilin-salt microextraction on permutite, the accepter phase is direct contact with the sample phase, which can cause the target analytes being polluted more or less, and their precisions limited.…”