中空纤维膜液相微萃取-高效液相色谱联用技术测定尿液中痕量己烯雌酚

采用中空纤维液相微萃取与高效液相色谱联用技术测定了尿液样品中的痕量己烯雌酚;考察了样品相酸度、中间相种类、接收相浓度、搅拌速度、萃取时间等对液-液-液三相微萃取效率的影响,进而确定了最佳萃取条件.结果表明,当样品相pH为2.5,中间相为甲苯,接收相为3μL 0.25mol/L氢氧化钠溶液,搅拌速度为800r/min,萃取时间为50min时,萃取效率最佳.在最佳萃取条件下,样品的回收率为76.4%,相对标准偏差为3.8%.     

离子液体-液相微萃取-高效液相色谱法测定纺织品中芳香胺

建立了一种基于1-丁基-3-甲基咪唑六氟磷酸盐离子液体的溶剂棒液相微萃取样品前处理技术,结合高效液相色谱法分析染色纺织品中源于禁用偶氮染料的8种致癌芳香胺的方法。考察了有机萃取溶剂、给出相pH值、搅拌速度、盐效应和萃取时间的影响,确定了以正辛醇为有机萃取溶剂,离子液体为接收相,给出相pH值为10并添加饱和NaCl溶液,搅拌速率为1000 r/min,萃取时间为40 min的芳香胺优化萃取条件。方法的线性范围宽,相关系数r>0.9986;检出限为0.014~2.1μg/L(S/N=3);相对标准偏差<4.6%(n=10);回收率为83.2%~91.2%;8种芳香胺的富集倍数在10~270倍之间。本法具有灵敏,萃取效率高,有机溶剂消耗少,操作简单、快捷等特点。     

液相微萃取-毛细管电泳联用对汗液基质中4种芳香胺的同时测定

采用纤维膜三相液相微萃取(HF-LLLME)技术,对汗液基质中的苯胺、邻甲苯胺、对氯苯胺、对硝基苯胺进行了分离富集。以正辛醇为有机相,在供体相pH为9.0,NaCl质量浓度为200g/L,接收相pH为1.0,萃取时间为60min的条件下,4种芳香胺的富集倍数为410～1250倍。将接收相直接进行毛细管电泳(CE)测定,样品相中4种芳香胺的质量浓度在10～100μg/L范围内与电泳峰面积呈良好线性,相关系数均大于0.992,4种芳香胺的检出限为1～10μg/L。运用该法对偶氮染料汗液环境下光致降解过程中产生的苯胺进行测定,回收率为91%～93%,结果满意。     

液-液-液三相液相微萃取-高效液相色谱法检测尿样中的安非他明和氯胺酮

建立了液-液-液三相液相微萃取与高效液相色谱联用技术测定尿样中的安非他明和氯胺酮的方法。考察了萃取溶剂、料液相pH值、搅拌速度、萃取时间和接受相HCl浓度等因素对富集因子的影响,得到了萃取溶剂为300 μL甲苯,料液相pH值为11,接受相为1.0 μL 0.1 mol/L HCl,搅拌速度为600 r/min,萃取时间为50 min的最佳实验条件。在该条件下,获得了较高的富集因子;方法的线性范围为安非他明0.01～10 μg/mL,氯胺酮0.01～5 μg/mL,相对标准偏差均小于2%,检测限均为5 ng/mL (S/N=3)。建立的三相液相微萃取方法能有效地去除复杂基体的干扰,有机溶剂消耗少,萃取效率高,是一种有效、灵敏的样品前处理方法,适合于尿样中安非他明和氯胺酮的测定。     

离子液体液-液萃取-高效液相色谱测定水中酚类化合物

建立了离子液体1-丁基-3-甲基咪唑六氟磷酸盐([C4mim][PF6])液-液萃取-高效液相色谱测定水中酚类化合物的方法.研究了水相pH值、萃取时间、水相体积及盐的浓度对萃取的影响.最佳萃取条件分别为:水相pH值为5,萃取时间为40 min,水相体积为60 mL.对比了离子液体对1-辛醇对苯酚、4-硝基苯酚、2-硝基苯酚、2,4-二甲基苯酚和双酚A的富集效率.在最佳条件下,离子液体对5种酚的富集倍率在9～151之间,方法对苯酚、4-硝基苯酚、2-硝基苯酚、2,4-二甲基苯酚和双酚A的检出限分别为:2.0、0.9、0.3、1.8和1.1 μg/L.将该方法应用于自来水、河水、湖水和污水的检测,回收率为87.9%～109.9%.     

液相微萃取-高效液相色谱法快速测定唾液中尼古丁含量

建立了一种以液相微萃取为样品前处理技术,结合高效液相色谱快速、有效测定唾液中尼古丁含量的方法。确定了以磷酸三丁酯为有机溶剂、2 mL 0.05 mol/L KOH调节2 mL样品溶液为给出相,10 mmol/LKH2PO4(pH=3.0)为接收相;搅拌速率为500 r/min,萃取时间为17 min的尼古丁优化萃取条件。方法的线性范围0.1-50 mg/L,相关系数r2=0.9996;检出限为0.05 mg/L(S/N=3);相对标准偏差<5%(n=5);相对回收率为96.3%-102.2%。实验证明该法可用于唾液等生物体液中碱性物质的测定。     

浸入式三相液相微萃取-高效液相色谱法对饮料中7种有机酸的同时测定

建立了一种利用三相液相微萃取(LPME)技术进行样品前处理、高效液相色谱(HPLC)法同时测定饮料中酒石酸、甲酸、乙酸、乳酸、琥珀酸、苹果酸和柠檬酸7种低相对分子质量有机酸的分析方法.考察了萃取溶剂、搅拌速率、盐效应、萃取时间、接收相和给出相pH值等因素对萃取效率的影响.优化后的实验条件:磷酸三丁酯(TBP)为萃取剂,萃取速率为1 000 r/min,萃取时间为35 min,给出相pH为2.5,接收相pH为12.0.该方法在较宽线性范围内显示了良好的线性关系(r＞0.993 6),检出限(S/N=3)为10.4 ～54.2 μg/L,相对标准偏差小于4.8%.7种有机酸的富集倍数为13.3 ～51.4,样品的加标回收率为85% ～103%.该方法操作简单、快速,只需使用极少量的有机溶剂,具有绿色环保的特点,可用于果汁饮料、红茶饮料及基质特别复杂的牛奶饮料中低分子量有机酸的测定,为分析复杂基质样品提供了有益的参考.     

水中酚类化合物的液-液-液微萃取/ 高效液相色谱联用分析研究

建立了液-液-液微萃取/高效液相色谱联用(LLLME/HPLC)测定环境水中痕量酚类化合物2-甲基苯酚、2-硝基苯酚、2,4-二氯苯酚的分析方法,研究了有机相溶剂种类及其体积、料液相pH值与离子强度、接受相的体积、组成及浓度和搅拌速率、萃取时间等因素对分析物萃取效率的影响。实验结果表明,该方法对酚类化合物的富集倍数可达到404~747倍,方法的线性范围为0.2~300μg/L,RSD(n=6)为6.8%~11.4%。测定加标自来水、江水以及生活污水样品的回收率为83%~110%。     

固相微萃取高效液相色谱法测定食品中己烯雌酚

建立了固相微萃取(SPME)-高效液相色谱(HPLC)联用测定食品中己烯雌酚(DES)的方法.考察了萃取纤维头、萃取时间、解吸时间和盐的添加对萃取效果的影响.在此基础上,采用正交试验,以解析液组成、萃取液pH和搅拌速度为3因素筛选出了最佳固相微萃取条件.该分析方法的线性范围为0.02 ～2.0μg/ml,工作曲线线性良...     

液相微萃取-高效液相色谱法测定尿样中的利多卡因

应用液相微萃取与高效液相色谱联用技术快速分析尿样中的利多卡因。考察了萃取溶剂、体积、萃取时间及料液pH值对液相微萃取的影响,建立了液相微萃取与高效液相色谱联用技术分析尿样中利多卡因的方法。优化的实验条件为：料液pH值12．0,萃取溶剂为5μL邻苯二甲酸二丁醅,萃取时间40min,搅拌速度80r／min。方法的线性范围为0．2-5mg／L;检出限为0．1mg／L;相对标准偏差小于6．3％。通过液相微萃取后,能有效地去除检测尿样中利多卡因的干扰物质,获得了较高的选择性。该方法简便、快速、灵敏、消耗有机溶剂少,是尿样中利多卡因检测的一种有效方法。     

中空纤维液相微萃取-高效液相色谱法测定纺织品中10种含氯苯酚类化合物

建立了中空纤维液相微萃取-高效液相色谱法测定纺织品中10种含氯苯酚类化合物的方法。系统地优化了影响萃取效率的因素,得到的最佳萃取条件为：萃取溶剂为正己烷,接受相NaOH溶液的浓度为0.10 mol/L,萃取时间为60 min,搅拌速度为600 r/min。在最佳萃取条件下,10种含氯苯酚在0.01～1.00 mg/L范围内线性关系良好（r>0.999）,10种含氯苯酚的检出限（信噪比为3）为0.01 mg/kg,富集倍数为95～101。在空白样品中添加0.01、0.05和0.1 mg/kg 3个不同水平的10种含氯苯酚类化合物,其平均回收率为78.8%～105.1%,相对标准偏差为0.3%～7.3%。研究结果表明该方法灵敏度高、简便、准确,可用于纺织品中含氯苯酚类化合物的测定。     

三相中空纤维膜液相微萃取-高效液相色谱法测定水中痕量双酚A

建立了三相中空纤维膜液相微萃取-高效液相色谱(HF-LPME-HPLC)方法,用于分析测定水中痕量双酚A的含量.设计了三相中空纤维膜液相微萃取系统,优化的HP-LPME最佳萃取条件为:萃取剂为正辛醇,接受相NaOH浓度为0.09 mol/L,样品溶液pH=4.0,NaC1加入量为30 g/L,搅拌速度为900 r/min,萃取时间为60 min.萃取后取20 μL接受相进行色谱分析.在最佳萃取条件下,方法的线性范围为0.5～200 μg/L(r＞ 0.999),检出限(信噪比为3)为0.2 μg/L;富集因子为241;方法RSD＜3.2％ (n=3).在实际环境水样中添加5,20和50μg/L的双酚A标准物质,加标平均回收率为92.8％～101.9％.表明本方法可用于水中痕量双酚A的快速准确测定.     

LC Determination of Mono-Substituted Phenols in Water Using Liquid–Liquid–Liquid Phase Microextraction

A simple liquid–liquid–liquid microextraction device of new design was used to pre-concentrate phenols from water samples before liquid chromatographic (LC) analysis. Extraction was induced by the pH difference inside and outside an organic phase located at the interface. The pH of the donor phase outside the organic phase was adjusted to 1 with HCl whereas the acceptor phase was a basic solution at pH 13. On stirring neutral phenols were extracted into the organic solvent then back-extracted into 1 μL of basic acceptor solution suspended from the tip of a micro syringe. The acceptor phase was then withdrawn into the micro syringe and injected directly into the LC. The technique uses a low-cost disposable extraction ‘device’ and is very convenient to operate. Up to 230-fold enrichment of analytes could be achieved. This procedure could also serve as a sample clean-up step because neutral and basic compounds were not extracted into the acceptor phase. The RSD (n = 5) was better than 6.2% and the linear calibration range was from 1 to 1000 µg–L⁻¹ with r ² ≥ 0.992.Optimization of experimental conditions (rate of stirring, ionic strength of the sample solution, concentration of reagents, time of extraction, and organic solvent volume) were also examined. The method was applied to the determination of phenols in tap and well waters.Revised: 14 February and 29 March 2005     

液相微萃取／高效液相色谱法测定环境水样中的痕量苯脲类除草剂

建立了液相微萃取／高效液相色谱联用(LPME／HPLC)技术同时测定环境水中痕量异丙隆、秀谷隆和灭草隆除草剂的分析方法.考察了不同萃取条件及测定条件对检测结果的影响.优化后的萃取条件为:6μL正辛醇作萃取剂,液滴体积3μL,搅拌速度450 r/min,萃取30 min.结果表明,在优化条件下,3种除草剂的质量浓度在0....     

Hollow‐fiber liquid‐phase microextraction combined with capillary HPLC for the selective determination of six sulfonylurea herbicides in environmental waters

A three‐phase hollow‐fiber liquid‐phase microextraction combined with a capillary LC method using diode array detection was proposed for the determination of six sulfonylurea herbicides, triasulfuron, metsulfuron‐methyl, chlorsulfuron, flazasulfuron, chlorimuron‐ethyl, and primisulfuron‐methyl, in environmental water samples. Different factors that can affect the extraction process such as extraction solvent, acidity of the donor phase, composition and pH of the acceptor phase, salt addition, stirring speed, and extraction time were optimized. Under the optimum conditions, detection and quantitation limits between 0.1 – 1.7 and 0.3 – 5.7 μg/L, respectively, and enrichment factors ranging from 71 to 548 were obtained. The calibration curves were linear within the range of 0.3 – 40 μg/L. Intra‐ and interday RSDs were <6.3 and 8.4%, respectively. The relative recoveries of the spiked ground and river water samples were in the range of 69.4 – 119.2 and 77.4 – 111.7%, respectively. The results of the study revealed that the developed methodology involves an efficient sample pretreatment allowing the preconcentration of analytes, combined with the use of a miniaturized separation technique, suitable for the accurate determination of sulfonylurea herbicides in water.     

液-液-液微萃取/高效液相色谱法测定人血浆中的西地那非和伐地那非

建立了液-液-液微萃取与高效液相色谱联用同时测定血浆中西地那非和伐地那非的方法。考察了萃取溶剂、溶剂体积、接受相液滴大小、搅拌速度和萃取时间等因素对富集因子的影响,得到了萃取溶剂为300 μL 甲苯、接受相为2 μL 0.2 mol/L HCl、搅拌速度为600 r/min和萃取时间为40 min的最佳实验条件。在该条件下,获得了较高的富集因子。两种组分的线性范围均为5 μg/L~1.0 mg/L,加标回收率高于87%,其相对标准偏差小于5%。以信噪比为3计,西地那非的检测限为1 μg/L,伐地那非为0.5 μg/L。该方法能有效地去除复杂基体的干扰,有机溶剂消耗少,萃取效率高,是一种有效的、灵敏的样品前处理方法,适用于血浆中微量西地那非和伐地那非的测定。     

Orthogonal array designs for the optimization of liquid-liquid-liquid microextraction of nonsteroidal anti-inflammatory drugs combined with high-performance liquid chromatography-ultraviolet detection

Orthogonal array designs (OADs) were applied for the first time to optimize liquid-liquid-liquid microextraction (LLLME) conditions for the analysis of three nonsteroidal anti-inflammatory drug residues (2-(4-chlorophenoxy)-2-methylpropionic acid, ketoprofen, and naproxen) in wastewater samples. Six relevant factors were investigated: type of organic solvent, composition of donor phase and acceptor phase, stirring speed, extraction time and salt concentration. In the first stage, mixed-level orthogonal array design, an OA16 (4(1) x 2(12)) matrix was employed to study the effect of six factors, by which the effect of each factor was estimated using individual contributions as response functions. Based on the results of the first stage, 1-octanol was chosen as organic solvent for extraction. The other five factors were selected for further optimization using an OA16 (4(5)) matrix and a 4 x 4 table to locate more exact levels for each variable. The relative standard deviations for the reproducibility of optimized LLLME varied from 6.2 to 7.1%. The coefficients of determination for calibration curves were higher than 0.9950. The method detection limits for drugs spiked in ultrapure water were in the range of 0.03-0.3 ng/mL. The final optimized conditions were applied to the analysis of drug residues in three wastewater samples in Singapore.     

Determination of estrogens in wastewater using three-phase hollow fiber-mediated liquid-phase microextraction followed by HPLC

Three-phase hollow fiber-mediated liquid-phase microextraction followed by HPLC was used for the determination of three synthetic estrogens, namely diethylstilbestrol, dienestrol, and hexestrol, in wastewater. Extraction conditions including organic solvent, volume ratio between donor solution and acceptor phase, extraction time, stirring rate, donor phase and acceptor phase were optimized. The target compounds were extracted from a 10 mL aqueous sample at pH 1.5 (donor solution) through a 45 mm in length hollow polypropylene fiber that was immersed in 1-octanol in advance, and then the hollow fiber was filled with 10 microL 0.5 mol/L sodium hydroxide solution (acceptor phase). After a 40 min extraction, the acceptor phase was directly injected into an HPLC system for detection. Under the optimized extraction conditions, a large enrichment factor (more than 300-fold) was achieved for the three estrogens. The determination limit at an S/N of 3 ranged from 0.25 to 0.5 microg/L for the estrogens. The recovery ratio was more than 86% in the determination of these estrogens in wastewater.     

中空纤维三相液相微萃取荧光光度法测定绿豆芽中的吲哚类植物生长素

基于中空纤维液相微萃取技术,建立了绿豆芽中吲哚类植物生长素的荧光检测方法。通过L9(34)正交实验,对中空纤维液相微萃取条件进行优化,得到的优化条件为:样品溶液的p H值调为4.0,萃取溶剂为正辛醇,接受相为p H 12.0的Na OH,搅拌速度为1 000 r/min,萃取时间为60 min。在最优萃取条件下,吲哚类植物生长素的富集倍数可达92倍。供体相中吲哚类植物生长素的质量浓度在1.71~50.0 mg/L范围内呈良好的线性关系,相关系数为0.997 9,检出限(S/N=3)为0.57 mg/L,样品的加标回收率为88.6%~100.7%,相对标准偏差(RSD)不大于4.8%。该方法操作简单,环境友好,可用于绿豆芽中吲哚类植物生长素含量的准确快速测定。     

液相微萃取/离子色谱测定牛奶中的氨

以水为微滴萃取溶剂,采用顶空液相微萃取/离子色谱检测了牛奶中的氨.优化了顶空液相微萃取的实验条件:pH=12,萃取温度为35 ℃,萃取时间为15 min,搅拌速率为800 r/min,萃取溶剂体积为5 μL.测定氨的线性范围为10 ～300 μg·L-1(R2=0.998),检出限达1.8 μg·L-1,回收率为92% ～105%.