High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry For Arsenic Speciation Analysis

With the advantages of simple measurement step,short measurement process,less pollution,high sensitivity,well selectivity,wide measurement range,low detection limit and small matrix effect,inductively coupled plasma-mass spectrometry(ICP-MS)has been widely used in the determination of trace and ultra-trace elements.High performance liquid chromatography(HPLC)has the advantages of high separation ability,good reproducibility and wide applications range.HPLC-ICP-MS combines the advantages of ICP-MS and HPLC such as high sensitivity,good selectivity,low detection limit,high separation ability and good reproducibility.Moreover,the interface of HPLC-ICP-MS is simple when it compared with the interface of other combined techniques.Nowadays,it has become one of the most potential combined techniques and has been widely used in the elemental speciation analysis.Elemental speciation analysis plays an important role in analytical chemistry.It is not sufficient by using the total amount of elements to evaluate the effects of element to biological and environmental system,which may result in a misguide.Since the bioavailability and toxicity of the elements are related not only to the amount of the elements,but also to the elemental speciation in the sample.Elemental speciation analysis is widely use in kinds of field including environmental science,biological science and pharmaceutical chemistry.Arsenic(As)is a widespread toxic element in nature,which can cause the cancer.The different forms of As can lead to different toxicity.Therefore,it is important to the speciation analysis of As.In this paper,tripterygium,cordata,the urine and plasma of the uremic patient and momordica grosvenori are selected as the research objects and the forms of As in the above sample were studied.The main contents and results are as follows:1.The arsenic speciation of tripterygium sample by high performance liquid chromatography and inductively coupled plasma mass spectrometry(HPLC-ICP-MS)has been developed.He was used as a collision gas for KED to eliminate interference of 40-Ar35Cl and improve the accuracy.Three extration reagents with ultrasonic mode have been evaluate in order to obtain good arsenic extraction efficiency in samples.The results showed that the extraction rate of ultrasonic assisted water-methanol(v/v = 1:1)extraction method was the best.The detection limits of AsC,AsB,As(III),DMA,MMA and As(V)were 0.0426,0.0267,0.0759,0.0356,0.0554 and 0.0613 ng-mL-1,respectively.The correlation coefficients were more than 0.9993.The tree arsenic speciation in tripterygium were found.Theconcentration of As(V),AsC and AsB were 0.945,0.500 and 0.626 ?g.g-1,respectively.The recoveries were more than 95.5%The relative standard deviation(RSD)was between 1.5%to 3.5%.The method is simple andquick.The six arsenic speciation was completely separated within 9 min.2.The arsenic speciation in houttuyniae cordata thunb(HCT)sample has been developed by high performance liquid chromatography and inductively coupled plasma mass spectrometry(HPLC-ICP-MS).The results showed that water,50%methanol,proteinase K + Lipase,pepsin and pepsin + nitrogen can extract arsenic speciation in HCT.However,pepsin + nitrogen was best in above extract reagents and was selected for arsenic speciation analysis in this paper.The results showed that HCT have four arsenic speciation such as AsB,As(III),DMA and As(V),their contents were 0.256,0.206,0.182 and 0.608 ug g-1,respectively.The recoveries were in the range of 96%?103%.The relative standard deviations(RSD,n = 6)for determining AsC,AsB,As(?),DMA,MMA and As(V)were between 1.6%to 2.5%and the detection limits were 0.0516,0.0489,0.0659,0.0421,0.0242 and 0.0187 ng.mL-1,respectively.The correlation coefficients(R2)were more than 0.9996.The method is simple rapid,effective,and provides an new method for arsenic speciation in HCT.3.The arsenic speciation of uremic patients serum and urine sample by high performance liquid chromatography and inductively coupled plasma mass spectrometry(HPLC-ICP-MS)has been developed.Water-methanol system was used as extract medium using ultrasonic-assistant extraction for determination of AsC,AsB,As(III),DMA,MMA and As(V).Their relative standard deviations(RSDs,n ?6)were between 1.8%to 2.7%,and the detection limits were 0.0156,0.0289,0.0359,0.0225,0.0342 and 0.0187 ng.mL-1,respectively.Their linear concentration ranges were 0.078?100,0.143?100,0.176?100,0.131?100,0.165?100 and 0.0911?100 ng.mL-1,respectively.The correlation coefficients(R2)were more than 0.9993.The results showed that the arsenic species of both healthy individuals and uremic patients were DMA,but the DMA concentration in uremic patients was greater than that before dialysis and healthy individuals.The urine samples of healthy people contained DMA and As(V).However,The urine samples of uremic patients contained DMA,As(V)and As(III).The recoveries ranged from 93%to 102%.The mehtod provided the convenience for field epidemiological investigation and clinical study.4.Arsenic speciation in fructus momordicae has been developed using magnetite solid phase extraction(MSPE)coupled HPLC-ICP-MS.The Fe3O4 magnetic nanoparticles were prepared with the ammonia as precipitant and chemical coprecipitation.The surface of magnetite nanoparticles was coated by glycerol-acetic acid catalyzing of tetraethyl silicate(TEOS),and then coated with cetyl trimethyl ammonium bromide(CTMAB).The CTMAB-SMNPs magnetic nanoparticles were obtained.The detection limits of DMA,MMA and As(V)were 0.0058,0.0029 and 0.0018 ng.mL-1,respectively.The relative standard deviations(RSD,n=6)were better than 2.1%.Their linear concentration ranges were 0.021?100,0.012?100 and 0.009?100 ng.mL-1,respectively.The correlation coefficients(R2)were higher than 0.9995.The concentrations DMA,MMA and As(V)in fructus momordicae were 0.150,0.130 and 0.310 ?g.g-1,respectively.The extraction efficiecies were more than98%,and recoveries were form 97%to 100.2%.