Application Of New Extraction Technique In Analysis Of Natural Active Compounds

As a new extraction technique,dispersed micro solid phase extraction(DMSPE)is widely used in the extraction of natural active compounds owing to its advantages of simplicity,reliability,efficiency,small amount of samples and reagents required.The most critical parameter of this method is the selection of sorbent materials for different analytes.Therefore,in order to improve the extraction efficiency of DMSPE,this study focused on the exploitation of new sorbent materials for different types of natural active compounds.Moreover,the extraction conditions were optimized.the developed methods were successfully applied to analyze the natural active compounds in real complex samples.The paper is mainly concerned with the following aspects:Firstly,a simple and efficient method combined IL-MAE with DMSPE using fluorinated carbon nanotube as a novel sorbent was developed for the extraction and analysis of sesquiterpenes(germacrone,furandiene and ?-elemene)in Curcuma wenyujin Y.H.Chen & C.Ling plant samples.The major parameters influencing the extraction performance including type of ionic liquids,concentration of 1-decyl-3-vinylimidazolium bromide,microwave time,microwave temperature,type of adsorbent,concentration of adsorbent,agitation time and elution conditions were investigated and optimized.The proposed method exhibited good linearities(R?0.9991)and the limits of detection(LODs)for the three sesquiterpenes were in the range of 0.092-6.700 ?g/mL.This proposed method was successfully applied in the extraction and determination of trace sesquiterpenoids in three batches of C.wenyujin samples and rat urine samples.Secondly,a simple,efficient and environmental friendly dispersive micro solid-phase extraction method coupled with high performance liquid chromatography using crab shell powder as an adsorbent was developed for preconcentration and determination of three flavonoids(quercetin,kaempferol and isorhamnetin)in complex matrix samples.The adsorption mechanism of crab shell powder in DMSPE has been explored for the first time.Parameters that affecting extraction efficiency were optimized.The optimal extraction conditions were using 2 ?g/mL of crab shell powder as the sorbent,extraction for 2 min at pH 7 and then eluting with 100 ?L of methanol.As a result,the method shows good linearity(R?0.9995),low limits of detection(0.080-0.250 ng/mL).This optimized approach was successfully applied to the extraction and analysis of flavonoids in honey and rat urine samples.Finally,a DMSPE method combined with HPLC-DAD has been proposed for the extraction and quantitative analysis of lignans(honokiol,magnolol)in complex matrix samples.To obtain the optimal performance of DMSPE procedure,several main parameters were investigated.And the optimal conditions were using 2 ?g/mL of silica gel as the sorbent,extraction for 2 min and then eluting with 100 ?L of methanol.The developed method provides good linearities(R?0.9998)and very low LODs(0.0097-0.0231 ng/mL).Finally,this presented method was applied to the extraction and determination of lignans in Huo xiang zheng qi oral liquid and rat urine samples successfully.