Study On The New Hollow Fiber Membrane Microextraction Coupling Technique In Quality Control Of Traditional Chinese Medicine

Hollow fiber membrane liquid phase microextraction techniques based on porous hollow fiber as the extraction solvent carrier,it integrates sampling,extraction and concentration as a whole,has low cost,simple equipment,good ability to purify the sample and resist the interference of the matrix.The main contents of this paper are as follows:A new method for determination of anthraquinones in Rhubarb and its pharmaceutical preparations was proposed using two phase hollow fiber solvent bar extraction coupled with HPLC-UV.In the HF-LPME procedure,PDVF hollow fiber was used for the microextraction of anthraquinones for the first time and chloroform was selected as the acceptor phase.Furthermore,the factors influencing the extraction efficiency anthraquinones such as the number of hollow fiber bars,pH of the sample solution,amount of salt,extraction time and desorption solvent,were investigated.Under the optimum extraction conditions,the calibration curves for emodin was linear over the range of 6.5-52?g/mL with correlation coefficients higher than 0.9990;The relative standard deviations?n=5?were less than 3%;Good recoveries from spiked samples?91.71%–98.04%?were obtained.The results obtained by the present method and the method mentioned in Chp2015 fit well in terms of the content of emodin and chrysophanol.A new nanocomposite membrane was used to clean up impurities from complex samples and the obvious synergy was obtained in this paper.The nanocomposite membrane was prepared by dispersing TiO₂ nanoparticles in chloroform and filled in the pores and lumen of hollow fiber membrane.The novel microextraction method showed the ideal selective extraction effect for alkaloids in the formulae composed of Rhizoma coptidis and the excellent clean-up efficiency compared with the single membrane method.The optimum extraction conditions were as follows:chloroform as accepted phase;the number of nanocomposite membrane fiber bars,7;extraction time,30 min;pH of the sample solution,10.55;desorption solvent,methanol.The limit of detection for the described alkaloids was estimated at 0.122?g/mL.The recovery of the four alkaloids in complex samples ranged from 93.24%to 97.94%with relative standard deviation of<4.99%?n=5?.A new microextraction enhancement technique for extraction of ginsenosides in Chinese compound formula containing Panacis quinquefolii Radix was realized by coupling hollow fiber liquid phase microextraction with Al₂O₃ sol-gel in this paper.The enhancement technique was prepared by dispersing Al₂O₃ sol-gel in n-butanol and filled in the pores and lumen of polyether sulphone membrane fiber.The optimum extraction conditions were as follows,n-butanol as acceptor phase;the number of hollow fiber bars was set 11;extraction time was set 50 min;methanol as desorption solvent.The limit of detection for ginsenoside Rg₁,Re,Rb₁ was 0.066,0.306,0.40?g mL^-1respectively.The extraction recovery ranged from 88.61%to 94.29%with RSDs<6.3%.This developed method was successfully applied to the analysis of ginsenoside in oral liquid and enzyme hydrolysis solution of Panacis quinquefolii Radix by high performance liquid chromatography?HPLC?.The results of the above experiments show that the hollow fiber membrane liquid phase microextraction coupled technology as a new sample pretreatment technology in the field of quality control of traditional Chinese medicine,especially for the low efficacy of traditional Chinese medicine and chemical composition of complex samples have a good application prospects.