亚胺连接的多孔共价有机骨架材料结合固相萃取-液相色谱-串联质谱检测蜂蜜中雌激素

以亚胺连接的多孔共价有机骨架材料(IL-COF-1)作为固相萃取的吸附剂,建立了液相色谱-串联质谱快速检测蜂蜜样品中痕量雌激素的方法。该研究选择雌二醇、己烯雌酚、雌三醇、β-雌二醇和炔雌醇5种雌激素作为目标分析物。在蜂蜜样品中添加雌激素,采用单因素优化法对影响萃取效果的重要因素进行优化,获得最佳条件:IL-COF-1用量为30 mg,样品流速为3 mL/min,样品溶液pH值为7,以5 mL的1%(v/v)氨水-甲醇溶液进行洗脱,流速为0.4 mL/min,萃取过程中不添加NaCl。采用高效液相色谱-三重四极杆质谱联用技术对提取物中的雌激素进行定量分析。以乙腈和5 mmol/L的乙酸铵溶液作为流动相进行梯度洗脱,经C18色谱柱分离,采用电喷雾离子源、质谱多反应监测和负离子扫描模式,实现了蜂蜜样品中5种雌激素的快速定性定量分析。在最佳条件下,方法验证结果中雌三醇、β-雌二醇和炔雌醇的线性范围为1~500 ng/g,雌二醇和己烯雌酚的线性范围为0.1~100 ng/g,相关系数(r)为0.9934~0.9972。检出限(S/N=3)为0.01~0.30 ng/g,定量限(S/N=10)为0.05~0.95 ng/g。添加50 ng/g 5种雌激素进行重复性实验,日内精密度相对标准偏差(RSD)为3.2%~6.6%,日间精密度RSD为4.2%~7.9%。基于IL-COF-1的固相萃取-液相色谱-串联质谱法具有快速准确、灵敏度高等特点,适用于蜂蜜中雌激素的分析和检测。将该方法应用于4个实际蜂蜜样品中雌激素的检测,均未检出目标物;在低中高3个水平下,5种雌激素的加标回收率为80.1%~115.2%,结果令人满意。     

串联双柱固相萃取-液相色谱-串联质谱法测定番茄酱中链霉素和双氢链霉素残留量

建立了同时测定番茄酱中链霉素和双氢链霉素残留量的串联双柱净化-液相色谱-串联质谱方法。样品中的残留物用磷酸盐缓冲液(pH 4)提取,经分散固相萃取净化和串联双柱固相萃取净化后,用极性色谱柱在梯度洗脱条件下分离待测物,采用正离子电喷雾离子源(ESI+)在多反应监测(MRM)扫描模式下进行测定,外标法定量。链霉素和双氢链霉素在0.01～0.2 mg/L质量浓度范围内线性关系良好,相关系数(r)大于0.999。链霉素和双氢链霉素的定量限均为0.02 mg/kg,回收率为71%～101%,相对标准偏差为2.3%～15%。该方法操作简便,净化效果好,灵敏,准确,适用于检测和分析番茄酱及其制品中链霉素和双氢链霉素残留量。     

Novel Method for Indirect Determination of Iodine in Marine Products by Atomic Fluorescence Spectrometry

A method for the determination of iodine based upon compound H₂HgI₄, formed between I^- and Hg²⁺ in nitric acid and extracted in methyl isobutyl ketone(MIBK), was developed via atomic fluorescence spectrometry(AFS). After the compound is reduced with potassium borohydrid(KBH₄), the resultant mercury vapor was injected into the instrument and iodine was, therefore, indirectly determined. Experimental parameters such as the conditions of extraction reagents, aqueous phase acidity, elemental mercury diffusion temperature in a vial and other factors were investigated and optimized. Under the optimum experimental conditions, this method shows a detection limit of 0.038 μg/L iodine and a linear relationship between 0.04―20 μg/L. The method was applied to determining the iodine content in marine duck eggs, kelps, laver and Ganoderma lucidum spirulina, showing a relative standard deviation(RSD) of 2.15% and the recoveries in the range of 98.1%―102.5%.     

Ionic Liquid-based Microwave-assisted Liquid-liquid Microextraction and High Performance Liquid Chromatography Determination of Sulfonamides from Animal Oils

The authors performed ionic liquid-based microwave-assisted liquid-liquid microextraction(IL-based MALLME) coupled with high performance liquid chromatographic separation for the determination of 6 sulfonamides (SAs) from animal oils. The target analytes were extracted from animal oil samples with sodium hydroxide solution containing 1-butyl-3-methylimidazolium tetrafluoroborateand as the extraction solvent under microwave irradiation. The experimental parameters of the IL-based MALLME, including types of ILs, volume of IL, amount of ion-pairing agent(NH₄PF₆), pH value of sample solution, and extraction temperature and time were evaluated. The limits of detection and quantification obtained were in a range of 0.4―0.5 μg/kg and a range of 1.2―1.8 μg/kg, respectively. The accuracy of the method was evaluated by analyzing five spiked animal oil samples at two fortified levels(5 and 50 μg/kg), and the recoveries of SAs varied from 81.4% to 114.5% with relative standard deviations ranging from 0.8% to 9.0%.     

Simple and Sensitive Determination of Aromatic Acids in Coconut Water by g-C3N4@SiO2Based Solid-phase Extraction and HPLC-UV Analysis

In this study, graphitic carbon nitride deposited silica(g-C₃N₄@SiO₂) was prepared by simple pyrolysis of melamine on silica and then used as a solid-phase extraction(SPE) sorbent for the extraction of four representative aromatic acids including benzoic acid(BA), salicylic acid(SA), indolyl-3-butyricacid(IBA) and naphthalene acetic acid(NAA) in coconut water(CW) samples. g-C₃N₄@SiO₂ exhibited an excellent adsorption capacity for the four aromatic acids, which are in the concentration range of 500-558.8 μg/g. The four aromatic acids could be directly captured by g-C₃N₄@SiO₂ from CW samples within 5 min. Thus, a rapid, simple and effective method for the analysis of four aromatic acids in CW samples was developed by coupling g-C₃N₄@SiO₂-based SPE with high performance liquid chromatography-ultraviolet(HPLC-UV) detection. The linearity of the developed method was in the range of 20-1000 ng/mL and its limit of detection was in the range of 1.9-5.7 ng/mL, which were signi-ficantly lower than those of the reported similar methods. The intra-day and inter-day precisions(based on the relative standard deviation, n=3) of the four aromatic acids were under 9.5% and 10.4%, respectively. The developed method was applied to determining the four aromatic acids in real CW samples and the spiked recoveries varied from 81.1% to 121.8%.     

固相萃取法与基质固相分散法在橙子中有机磷农药残留分析中的应用

建立了固相萃取(SPE)-反相高效液相色谱(RP-HPLC)同时测定橙子中痕量辛硫磷、二嗪农有机磷农药残留量的方法。样品经甲醇超声提取、C18固相萃取柱净化后,采用液相色谱柱分离,以乙腈-水(体积比为85∶15)为流动相等度洗脱,于254 nm下紫外检测。结果表明:在0.1～10.0 mg/L和0.4～10.0 mg/L范围内,辛硫磷、二嗪农的质量浓度与峰面积呈良好的线性关系;样品的加标平均回收率为87.3%～102.7%,相对标准偏差(RSD)为0.9%～4.9%。将该分析结果与用基质固相分散法(MSPD)处理样品所得的结果相比较,发现SPE对二嗪农的提取效果较好,而MSPD对辛硫磷的提取效果较好,但两种方法都能较好地净化样品,均能满足残留量的分析要求。     

UiO-66-NH_(2)@纤维素复合气凝胶用于保健品中西地那非的固相萃取北大核心CSCD

研究建立了一种基于UiO-66-NH_(2)@纤维素复合气凝胶的高灵敏度固相萃取新方法,与高效液相色谱法联用用于保健品中西地那非的检测。先将纤维素进行醛基和酰肼基的功能化,然后将两种功能化的纤维素通过交联并负载UiO-66-NH_(2)形成复合气凝胶。将此复合气凝胶作为固相萃取的吸附剂使用时,易于收集且不需要外加磁场或者抽真空的辅助作用,操作简单。研究对制备所得的UiO-66-NH_(2)@纤维素复合气凝胶进行了X-射线粉末衍射、扫描电镜、红外光谱和N_(2)吸附等表征,结果显示UiO-66-NH_(2)成功负载于气凝胶的孔道中,纤维素气凝胶掺杂了UiO-66-NH_(2)之后其孔道结构变得规整,并且比表面积增大。研究优化了复合气凝胶中UiO-66-NH_(2)的负载量对萃取的影响,高比例的负载量有利于西地那非的富集,并且最高的负载率为50%。研究优化了影响西地那非富集效率的实验条件,包括溶液pH、萃取时间、洗脱剂类型、洗脱时间、洗脱体积和离子强度。采用安捷伦Zorbax Eclipse Plus C18色谱柱(150 mm×4.6 mm,5μm)进行分离,以含0.1 mol/L三乙胺的磷酸盐水溶液(pH=6.50)-乙腈(30∶70,v/v)为流动相进行洗脱,检测波长为292 nm。在最佳的萃取条件下(pH为9.0,萃取时间为60 min,洗脱剂为乙腈,洗脱液体积为3×2 mL,洗脱时间为40 min),该分析方法的线性范围为10~2000 ng/mL(相关系数R^(2)=0.9949),检出限(LOD,S/N=3)为2.85 ng/mL,富集因子为59.17。将该方法用于保健品中西地那非的萃取,所得回收率为74.93%~89.12%,相对标准偏差为2.8%~5.3%,表明了方法的回收率和精密度良好,说明了该方法具有应用于保健品中西地那非日常检测的潜力。     

基于通过型固相萃取-超高效液相色谱-串联质谱法同时测定牛蛙中9种雌激素北大核心CSCD

建立了基于通过型固相萃取小柱净化的超高效液相色谱-三重四极杆质谱联用(UPLC-MS/MS)同时快速准确测定牛蛙中9种雌激素(雌三醇(E3)、17β-雌二醇(β-E)、17α-雌二醇(α-E)、17α-炔二雌醇(EE2)、雌酮(EI)、己烯雌酚(DES)、己二烯雌酚(DE)、己烷雌酚(HEX)、醋酸双烯雌酚(DD))残留的检测方法。样品经乙腈提取,经PRiME HLB固相萃取柱净化,Waters Acquity UPLC BEH C_(18)柱(100 mm×2.1 mm,1.7μm)分离,以0.5 mmol/L氟化铵水溶液-乙腈体系为流动相梯度洗脱,流速为0.3 mL/min,采用电喷雾正负离子切换模式(ESI^(+)/ESI^(-))和多反应监测(MRM)扫描方式检测,基质匹配外标法定量分析。该研究优化了液相色谱条件,相比于乙酸铵水溶液-乙腈体系和氨水溶液-乙腈体系,0.5 mmol/L氟化铵水溶液-乙腈体系作为流动相时9种雌激素普遍具有更佳的灵敏度。相比于甲醇和乙酸乙酯,乙腈作为提取溶剂时9种雌激素的提取率提高15%~40%。考察了HLB、C_(18)、Silica、PRiME HLB共4种不同类型的固相萃取小柱的基质净化效应,结果表明,PRiME HLB柱具有更好的基质净化能力。经PRiME HLB净化后,所有化合物的回收率均在70%~125%之间。DD的回收率从47%提高到74%,DES的回收率从180%降低到123%,有效减弱了基质效应。在最佳的实验条件下,E3、β-E、α-E、EI、DE、HEX、DD的线性范围为0.5~100.0μg/L,EE2和DES的线性范围为1.0~100.0μg/L,9种雌激素在各自的线性范围内均有良好的线性关系,相关系数为0.9953~0.9994,方法检出限为0.17~0.33μg/kg,方法定量限为0.5~1.0μg/kg,在2.0、10.0、80.0μg/kg 3个加标水平下,9种雌激素的加标回收率为65.1%~128.2%,相对标准偏差为1.9%~17.6%。该方法操作简便、快速、灵敏,重复性好,可用于大批量样品的同时快速准确检测。     

固相萃取-气相色谱-负化学源质谱法测定人血清中的多溴联苯醚

采用OasisHLB固相萃取柱萃取血清中的多溴联苯醚(PBDEs),经浓硫酸柱上除脂后,利用气相色谱-负化学源质谱法测定BDE-17、28、47、66、99、100、153、154、183和209共10种PBDEs组分。BDE-209的测定采用DB-5 ms色谱柱(15 m×0.25 mm×0.1 μm),其他组分采用VF-5 ms色谱柱(30 m×0.25 mm×0.25 μm)。对样品中蛋白质的去除溶剂和固相萃取条件(如洗脱溶剂及其用量)进行了优化。胎牛血清中的加标回收试验结果显示,各PBDEs单体相对于内标的平均回收率为78.5%～109.7%,日内测定的相对标准偏差(RSD)为0.3%～7.4%,日间测定的RSD为1.4%～14.1%。胎牛血清中三溴～七溴联苯醚的检出限(信噪比为3)为0.10～0.27 ng/L;定量限(信噪比为10)除了BDE-209为7.91 ng/L外,其他PBDEs为0.35～0.91 ng/L。采用本方法测定标准参考物质SRM1957和SRM1958,结果在参考值范围内。实验结果表明,本方法灵敏度高、准确度和精密度好,简便快速,溶剂消耗量少,适用于人体血清中三至十位溴取代联苯醚的测定。     

分散固相萃取-液相色谱-串联质谱法测定淡水鱼中柱孢藻毒素、节球藻毒素和微囊藻毒素

建立了同时检测淡水鱼中柱孢藻毒素、节球藻毒素、微囊藻毒素-RR、微囊藻毒素-YR及微囊藻毒素-LR的分散固相萃取-液相色谱-串联质谱方法。样品粉碎后，用乙腈-水-甲酸（89 ∶ 10 ∶ 1，v/v/v）提取目标物，C₁₈分散固相萃取柱净化，Agilent ZORBAX Eclipse XDB C₁₈色谱柱分离，乙腈和水梯度洗脱，在多反应监测（MRM）模式下进行定性分析，基质匹配标准曲线外标法定量。考察了提取溶剂及吸附剂种类对提取效率和净化效果的影响，并优化了液相色谱-串联质谱条件。该法在各自范围内具有良好线性关系，相关系数（R²）≥0.9954；检出限为5~10 μg/kg，定量限为15~40 μg/kg；样品的加标回收率为62.3%~101.2%。该方法前处理方法简单快速，灵敏高效，适用于淡水鱼中柱孢藻毒素、节球藻毒素和微囊藻毒素的有效检测。     

Microwave-assisted extraction of pyrethroid insecticides from semi permeable membrane devices (SPMDs) used to indoor air monitoring

A rapid and environmentally friendly methodology was developed for the extraction of pyrethroid insecticides from semi permeable membrane devices (SPMDs), in which they were preconcentrated in gas phase. The method was based on gas chromatography mass–mass spectrometry determination after a microwave-assisted extraction, in front of the widely employed dialysis method. SPMDs were extracted twice with 30 mL hexane:acetone, irradiated with 250 W power output, until 90 °C in 10 min, this temperature being held for another 10 min. Clean-up of the extracts was performed by acetonitrile–hexane partitioning and solid-phase extraction (SPE) with a combined cartridge of 2 g basic-alumina, deactivated with 5% water, and 500 mg C₁₈.

Pyrethroids investigated were Allethrin, Prallethrin, Tetramethrin, Bifenthrin, Phenothrin, λ-Cyhalothrin, Permethrin, Cyfluthrin, Cypermethrin, Flucythrinate, Esfenvalerate, Fluvalinate and Deltamethrin. The main pyrethroid synergist compound, Pyperonyl Butoxide, was also studied. Limit of detection values ranging from 0.3 to 0.9 ng/SPMD and repeatability data, as relative standard deviation, from 2.9 to 9.4%, were achieved. Pyrethroid recoveries, for spiked SPMDs, with 100 ng of each one of the pyrethroids evaluated, were from 61 ± 8 to 103 ± 7% for microwave-assisted extraction, versus 54 ± 4 to 104 ± 3% for dialysis reference method. Substantial reduction of solvent consumed (from 400 to 60 mL) and analysis time (from 48 to 1 h) was achieved by using the developed procedure.

High concentration levels of pyrethroid compounds, from 0.14 to 7.3 μg/SPMD, were found in indoor air after 2 h of a standard application.     

柱前衍生-超高效液相色谱-串联质谱法同时检测茶叶中草甘膦和草铵膦的残留量

采用超高效液相色谱-串联质谱建立了茶叶中草甘膦和草铵膦残留同时快速测定的方法。茶样经超纯水、二氯甲烷提取和C₁₈固相萃取柱净化后,在硼酸盐缓冲液中与9-芴甲氧羰酰氯(FMOC-Cl)进行衍生反应,衍生后产物在C₁₈色谱柱上进行超高效液相色谱分离;质谱检测采用电喷雾正离子化模式和多反应监测模式。结果表明,在0.003125~0.1 mg/L范围内,草甘膦和草铵膦均有良好的线性关系(r> 0.990),检出限(LOD)均为0.03 mg/kg;在添加浓度为0.375、1.5和4.5 mg/kg时,草甘膦的平均回收率为87.37%~99.11%,相对标准偏差(RSD)(n=6)为0.68%~1.35%;草铵膦的平均回收率为81.44%~86.17%,RSD(n=6)为1.01%~2.33%。该方法样品前处理简单,分析时间短,回收率和精密度等均符合农药多残留检测技术的要求,适用于茶叶中草甘膦和草铵膦残留的同时检测。     

离子色谱法测定三磷酸腺苷二钠制剂中主成分及有关物质的含量

建立了用于三磷酸腺苷二钠制剂中主成分及有关物质含量测定的离子色谱方法。采用IonPac AS11-HC色谱柱,以KOH溶液为淋洗液,梯度洗脱,流速为1.0 mL/min,进样10 μL,以Dionex AERS 500 4-mm抑制器的电导检测器检测,三磷酸腺苷二钠(ATP-Na₂)的含量按峰面积以外标法计算,二磷酸腺苷二钠(ADP-Na₂)及单磷酸腺苷二钠(AMP-Na₂)按加校正因子的主成分自身对照法计算,未知杂质按主成分自身对照法计算。ATP-Na₂、ADP-Na₂及AMP-Na₂的线性范围分别为0.000146~1.83 g/L、0.000484~1.51 g/L及0.000426~0.804 g/L,相关系数分别为0.9997、0.9996及0.9999;对照品溶液在24 h内的稳定性良好(峰面积RSD分别为1.3%、1.4%、2.5%);ATP-Na₂、ADP-Na₂、AMP-Na₂的方法定量限(S/N=10)分别为1.5 ng、4.8 ng、4.3 ng,检出限(S/N=3)分别为0.58 ng、1.21 ng、1.28 ng;ATP-Na₂在3个水平的加样回收率分别为96.50%、96.57%和96.77%。本方法适用于三磷酸腺苷二钠制剂的质量控制。     

气相色谱-电子捕获检测法测定海水中十氯酮残留

通过考察提取溶剂、毛细管柱、净化条件及共溶出干扰物等因素对十氯酮测定的影响,建立了二氯甲烷液-液富集萃取、硫酸净化分离、气相色谱法(GC)-电子捕获检测器(ECD)测定海水介质中有机氯农药类持久性有机污染物十氯酮残留分析方法。1 L海水经50 mL二氯甲烷萃取富集,浓缩后采用硫酸净化,以1%(体积分数)甲醇/正己烷混合溶液转移定容后,采用DB-5非极性毛细管柱进行GC分离,电子捕获检测器可测定其中十氯酮的含量;该方法采用外标法定量,在5～100 μg/L范围内呈线性,线性相关系数为0.9989。低、中、高3个浓度水平的平均加标回收率为81%～108%,相对标准偏差为1.2%～5.1%(n=6)。方法的检出限为0.6 ng/L。结果表明,该方法灵敏度高,线性关系好,可以满足简便、快速、准确测定海水中十氯酮的要求。     

固相萃取-超高效液相色谱-串联质谱法同时测定饲料中的3种雌激素

建立了固相萃取-超高效液相色谱-串联质谱(SPE-UPLC-MS/MS)同时测定饲料(预混合、配合和浓缩饲料)中3种雌激素(17β-雌二醇、苯甲酸雌二醇和戊酸雌二醇)的检测方法。饲料样品经乙腈提取,Heaion C₁₈固相萃取柱净化后,用ACQUITY UPLC BEH C₁₈色谱柱(50 mm×2.1 mm,1.7 μm)分离,乙腈和0.1%氨水溶液作为流动相进行梯度洗脱,多反应监测(MRM)模式检测,内标法定量。结果表明,17β-雌二醇和戊酸雌二醇在10~200 μg/L、苯甲酸雌二醇在5~200 μg/L范围内具有良好线性,相关系数(r)≥0.996。17β-雌二醇、苯甲酸雌二醇和戊酸雌二醇的检出限分别为7、5和7 μg/kg。样品的平均加标回收率为96.5%~102.0%。该法前处理操作简便、分析速度快、检出限低、准确度高,可用于饲料中3种雌激素的同时检测。     

Quantitation of nifedipine in human plasma by on-line solid-phase extraction and high-performance liquid chromatography

An analytical methodology for nifedipine quantitation in plasma by on-line solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) is described. The SPE cartridges contain C₂ and the analytes nifedipine and nitrendipine (internal standard) are separated on a C₁₈ column with a mobile phase consisting of acetonitrile–13 mM phosphate buffer pH 7 (65:35, v/v) followed by UV detection at 338 nm. Validation of the method demonstrated good recoveries (>90%), sensitivity (limit of quantification, 2 ng/ml), based on a 500 μl sample volume, accuracy and precision (<5.5% in concentrations greater than the limit of quantitation). This methodology has been used for bioequivalence studies.     

Interlaboratory study of a multiresidue gas chromatographic method for determination of organochlorine and pyrethroid pesticides and polychlorobiphenyls in milk,fish, eggs,and beef fat

An interlaboratory study was conducted to validate a gas chromatographic (GC) method for determination of 21 organochlorine pesticides, 6 pyrethroid pesticides, and 7 polychlorobiphenyl (PCB) congeners in milk, beef fat, fish, and eggs. The method was performed at low contamination levels, which represent relevant contents in food, and is an extension of the European standard (method NF-EN-1528, Parts 1-4). It enlarges the applicable scope of the reference EN method to pyrethroid pesticides and proposes the use of solid-phase extraction (SPE) as a cleanup procedure. Cryogenic extraction was made, and SPE cleanup was performed with 2 successive SPE cartridges: C18 and Florisil. After injection of the purified extract onto a GC column, residues were measured by electron capture detection. Food samples (liquid milk, beef fat, mixed fish, and mixed eggs) were prepared, tested for homogeneity, and sent to 17 laboratories in France. Test portions were spiked with 27 pesticides and 7 PCBs at levels from 26 to 45, 4 to 27, 31 to 67, and 19 to 127 ng/g into milk, eggs, fish, and fat, respectively. Based on results for spiked samples, the relative standard deviation for repeatability ranged from 1.5 to 6.8% in milk, 3 to 39% in eggs, 4.5 to 12.2% in fish, and 7 to 13% in fat. The relative standard deviation for reproducibility ranged from 33 to 50% in milk, 29 to 59% in eggs, 31 to 57% in fish, and 30 to 62% in fat. This method showed acceptable intra- and interlaboratory precision data, as corroborated by HORRAT values at low levels of pesticide and PCB contamination. The statistical evaluation of the results was performed according to the International Organization for Standardization (ISO; ISO 3534 standard) and 5725-2 Guideline.     

固相萃取-超高效液相色谱-高分辨质谱法快速测定食用油中4种酚类环境雌激素残留

建立了固相萃取-超高效液相色谱-高分辨质谱(SPE-UPLC-HRMS)快速测定食用油中4种痕量酚类环境雌激素(双酚S(BPS)、双酚F(BPF)、双酚A(BPA)和4-壬基酚(4-NP))的分析方法。食用油样品经乙腈涡旋提取和SLC玻璃固相萃取小柱净化后,以0.05%(v/v)三乙醇胺和甲醇溶液为流动相进行梯度洗脱,采用Waters ACQUITY UPLC HSS T3色谱柱(100 mm×2.1 mm,1.8μm)进行分离,在电喷雾离子源负离子模式(ESI-)和选择性离子监测(SIM)模式下进行检测,内标法定量。4种目标物在各自的范围内有良好的线性关系,相关系数(r)0.999。方法的检出限(LOD,S/N=3)和定量限(LOD,S/N=10)分别为0.03~0.11μg/kg和0.10~0.36μg/kg。在1.0、10.0和80.0μg/kg 3个加标水平下,4种目标物的加标回收率为86.3%~96.1%,相对标准偏差(RSD)为2.2%~8.8%(n=6)。基质效应实验表明方法在低、中、高3个浓度水平下均无明显的基质干扰。该法简便、快速,能用于食用油中双酚S、双酚F、双酚A和4-壬基酚残留的快速检测。     

基质固相分散萃取-高效液相色谱-串联质谱法分析拟南芥中的赤霉素

建立了基质固相分散萃取-高效液相色谱-串联质谱法(MSPD-HPLC-MS/MS)同时测定拟南芥中3种赤霉素GA1, GA3和GA4的分析方法。将拟南芥样品与C18填料混合研磨制成MSPD柱,并采用80%冷甲醇洗脱。采用反相C18色谱柱进行分离,以0.05%甲酸水溶液和乙腈为流动相进行梯度洗脱,采用电喷雾离子源负离子模式(ESI~)电离,多反应监测模式检测。对样品前处理条件、色谱分离条件和质谱检测条件进行了优化,结果表明,在最优条件下,3种赤霉素在10～300 ng/g范围内均呈良好线性关系,相关系数(r2)均大于0.98,检出限在1.1～4.1 ng/g之间。在10～50 ng/g添加水平下,平均回收率范围为54.7%～102.6%,相对标准偏差（RSD,n=3)为3.2%～12.8%。该方法操作简单、灵敏度高、选择性好、回收率高,适合拟南芥中GA1、GA3、GA4含量的测定。     

固相萃取结合超高效液相色谱-串联质谱法及气相色谱-负化学源质谱法测定人血清中的四溴双酚A、六溴环十二烷和多溴联苯醚

建立了固相萃取同时提取、净化血清中四溴双酚A(TBBPA)、α, β, γ-六溴环十二烷(HBCD)和8种多溴联苯醚(PBDEs)同系物的样本前处理方法,并结合色谱-质谱分离分析技术检测人血清样本中该类化合物的含量。试样在加入各自的同位素内标物后以甲基叔丁基醚/正己烷(1:1, v/v)混合溶剂进行萃取,再经浓硫酸去除脂肪后,以LC-Si固相萃取柱分离HBCD/TBBPA和PBDEs。采用分步检测的方式,在50 mm长BEH C18反相色谱柱上以超高效液相色谱-串联质谱(UPLC-MS/MS)的多反应监测模式(MRM)检测HBCD和TBBPA,在15 m长的毛细管柱上以气相色谱-负化学源质谱(GC-NCI/MS)的选择离子监测模式(SIM)检测PBDEs。以胎牛血清为空白基质,当HBCD、TBBPA和BDE-209的加标水平为0.5 ng/g和5 ng/g、三溴至七溴联苯醚的加标水平为0.05 ng/g和0.5 ng/g时,它们的平均加标回收率为80.3%～108.8%,相对标准偏差为1.02%～11.42%(n=5);以信噪比(S/N)为3计算,方法的检出限(LOD)为1.81～42.16 pg/g。采用该方法对实际样品进行测定,结果表明,本方法快速、准确、灵敏度高,能够满足血清中HBCD、TBBPA和PBDEs残留的同时提取及测定的要求。