固相萃取高效液相色谱法测定乳粉中苯并咪唑类药物残留

研究了乳粉中丙硫咪唑、噻苯咪唑、苯硫咪唑、噻苯咪唑酯、苯亚砜苯咪唑等五种苯并咪唑类药物液相色谱测定方法。乳粉中苯并咪唑类药物残留经碱性乙酸乙酯提取,Waters Oasis HLB固相萃取柱净化,以Cloversil C18柱为固定相,甲醇和0．02mol／LKH2P04为流动相,紫外检测器下测定。该法检出限为0．020mg／kg,添加标准0．10mg／kg的回收率为71％-90％。     

PSA分散固相萃取和离子对液相色谱测定蔬菜中苯并咪唑类残留的研究

建立了蔬菜中多菌灵、甲基硫菌灵、噻菌灵3种苯并眯唑类杀菌剂及其有毒代谢物2-氨基苯并咪唑残留的离子对液相色谱测定方法.样品用乙腈提取和无水硫酸镁盐析后,上层乙腈经PSA和无水硫酸镁混合振荡离心除去杂质和乙腈层中残余水分,再加入离子对试剂,用反相离子对高效液相色谱分离测定.多菌灵、甲基硫菌灵、噻菌灵的添标回收率在80%～110%之间,2.氨基苯并咪唑的回收率在70%～85%之间.多菌灵、甲基硫菌灵、噻菌灵和2-氨基苯并咪唑在实际样品中的检出限分别为0.07、0.09、0.05、0.10 mg/kg.     

高效液相色谱法测定壮阳保健品中4种硫代西地那非类药物

提出了用高效液相色谱法测定壮阳保健品中4种非法加入的硫代西地那非类药物的方法。样品用乙腈-水(1+1)溶液超声提取。用ACE C18色谱柱分离,柱温为35℃,进样量为10μL,所用流动相为由(A)三乙胺溶液-甲醇-乙腈(60+20+20)混合液和(B)三乙胺溶液-甲醇-乙腈(8+46+46)混合液,以不同体积比混合的溶液进行梯度淋洗。检测波长为230nm。4种药物的线性范围均在1.00~100mg·L-1范围内,检出限(3S/N)均为67μg·kg-1。加标回收率在92.0%~101%之间,测定值的相对标准偏差(n=6)均小于1.5%。对阳性样品进一步用LC-MS/MS确证。此外,还研究了硫代西地那非的二级质谱裂解规律和紫外光谱特征。     

液相色谱串联质谱法测定果蔬中的唑虫酰胺、氟啶虫酰胺、氯虫苯甲酰胺及氟虫双酰胺残留

建立了同时测定蔬菜和水果中唑虫酰胺、氟啶虫酰胺、氯虫苯甲酰胺和氟虫双酰胺残留量的液相色谱-串联质谱(LC-MS/MS)分析方法。样品经乙腈提取,过滤后进行盐析,上层有机相经QuEChERS方法净化浓缩后,用乙腈-水(体积比20∶80)定容进行分析。采用XBridgeTMC18色谱柱,以0.1%甲酸溶液-乙腈体系进行梯度洗脱,MRM方式测定,基质外标法定量。在优化条件下,唑虫酰胺和氟啶虫酰胺的线性范围为0.075~2.0 mg.L-1,氯虫苯甲酰胺和氟虫双酰胺为0.015~0.40 mg.L-1,线性相关系数均不低于0.998。唑虫酰胺、氟啶虫酰胺、氯虫苯甲酰胺及氟虫双酰胺在蔬菜和水果样品中的检出限(S/N=3)为0.000 8、0.005、0.002、0.000 5 mg.kg-1。蔬菜和水果中4种农药在0.05~5.0 mg.kg-1(氟啶虫酰胺和唑虫酰胺)和0.01~1.0 mg.kg-1(氟虫双酰胺和氯虫苯甲酰胺)加标范围内的回收率为80%~95%,批内RSD为2.0%~6.1%,批间RSD为3.3%~7.6%。     

液相色谱-串联质谱法测定化妆品中9种禁用芳香胺

应用液相色谱-串联质谱法测定化妆品中联苯胺、4,4′-二氨基二苯醚、邻氨基甲苯醚、3,3′-二甲基联苯胺、2,4,5-三甲基苯胺、4,4′-二氨基二苯硫醚、5-硝基-邻甲苯胺、3,3′-二氯联苯胺、4-氨基偶氮苯等9种禁用芳香胺的含量。样品经1%(φ)三氯乙酸溶液和乙腈提取,分取部分上清液经固相萃取小柱净化。所得净化液以C18色谱柱(50mm×4.6mm,1.8μm)为分离柱,以不同体积比的0.05%(φ)甲酸溶液和含0.05%(φ)甲酸的乙腈的混合液为流动相进行梯度洗脱,采用电喷雾正离子源多反应监测模式检测。3,3′-二氯联苯胺的线性范围为0.5~50mg·kg-1,检出限(3S/N)为0.15mg·kg-1。其余8种芳香胺的线性范围均为0.2~50mg·kg-1,检出限(3S/N)均为0.05mg·kg-1。加标回收率在78.3%~103%之间,测定值的相对标准偏差(n=6)均小于6.0%。     

亲水色谱柱-超高效液相色谱法测定饲料中纳多洛尔含量

用Waters AcQuity BEH Hilic亲水色谱柱-超高效液相色谱法测定了饲料中纳多洛尔的含量。样品先后2次用1%(φ)酸化甲醇溶液15,10mL超声提取,合并两次上清液,并分取5mL,通过MCX SPE小柱净化。用5%(φ)氨化甲醇溶液5mL洗脱。洗脱液在40℃用吹氮蒸干。残渣用由乙腈、0.5%甲酸溶液和水以体积比10比15比75组成的混合液1mL溶解,分取1.0μL进行色谱分析。采用亲水色谱柱为固定相及上述乙腈-甲酸溶液-水的混合液作流动相,纳多洛尔得到很好分离,纳多洛尔的质量浓度在0.01~20mg·L-1之间与峰面积呈线性关系。方法的测定下限(10S/N)为0.01mg·kg-1。用标准加入法测得回收率在78.5%~95.0%之间,测定值的相对标准偏差(n=5)均小于8%。     

高效液相色谱法测定果汁和果蔬中柑橘红2号染料

应用高效液相色谱法测定果汁、果蔬中柑橘红2号染料的含量。样品用丙酮-正己烷(1+3)混合溶剂提取,提取液于45℃蒸发至干。用甲酸-乙腈(0.5+99.5)溶液(经正己烷饱和)溶解残渣,正己烷脱脂。以Agilent TC C18色谱柱为分离柱,以乙腈与甲酸(0.1+99.9)溶液按体积比92比8混合作为流动相,用二极管阵列检测器在波长508 nm处进行测定。柑橘红2号染料的质量浓度在0.25~10.0 mg·L-1范围内与其峰面积呈线性关系,测定下限(10S/N)为0.1 mg·kg-1。以果汁、鲜橙和胡萝卜样品为基体,加入3种不同浓度水平的柑橘红2号标准溶液做回收试验,测得回收率在96.3%~104.0%之间,相对标准偏差(n=6)在1.0%~3.6%之间。     

超高效液相色谱-串联质谱法测定饲料中氨苯胂酸和洛克沙胂

采用超高效液相色谱-串联质谱法测定饲料中氨苯胂酸和洛克沙胂的含量。粉碎过筛后的样品用乙腈(1+1)溶液超声提取30min,离心后,上清液用二氯甲烷净化,取水层(上层)过0.22μm水系滤膜。以Thermo HYPERCARB色谱柱为固定相,以不同体积比的0.05%(体积分数)甲酸溶液和乙腈混合液为流动相进行梯度洗脱,串联质谱分析中采用电喷雾负离子源和多反应监测模式。氨苯胂酸和洛克沙胂的质量浓度均在0.05～10.0mg·L~(-1)内与其对应的峰面积呈线性关系,检出限(3S/N)为0.01～0.05mg·kg~(-1)。以空白样品为基体进行加标回收试验,所得回收率为82.0%～106%,测定值的相对标准偏差(n=6)为1.0%～7.9%。     

超高效液相色谱-串联质谱法测定乳制品中苯并咪唑类药物及其代谢物的残留量

乳制品样品中加入水、乙腈、氯化钠提取,采用乙腈饱和的正己烷脱脂净化。采用超高效液相色谱-串联质谱法测定样品溶液中苯并咪唑类药物及其代谢物的残留量。以Atlantis T3色谱柱为固定相,以不同体积比的0.1%(体积分数,下同)甲酸乙腈溶液和0.1%甲酸溶液的混合液为流动相进行梯度洗脱,串联质谱分析中采用电喷雾离子源(正离子扫描)和可编辑多反应监测模式。采用同位素内标法定量,苯并咪唑类药物及其代谢物的线性范围均为0.02～5.0μg·L~(-1),检出限(3S/N)为0.010～1.0μg·kg~(-1),测定下限(10S/N)为0.025～4.0μg·kg~(-1)。以空白样品为基体进行加标回收试验,所得回收率为81.4%～108%,测定值的相对标准偏差(n=6)为0.40%～9.3%。     

QuEChERS净化-超高效液相色谱-串联质谱法测定柑橘中7种保鲜剂的残留量

提出了同时测定柑橘中多菌灵、2,4-滴、咪鲜胺、抑霉唑、噻菌灵、嘧霉胺、甲基硫菌灵等7种保鲜剂残留量的QuEChERS-超高效液相色谱-电喷雾串联四极杆质谱法。用5%(φ)甲酸-乙腈溶液提取样品中的保鲜剂后加入盐析剂分层,上清液放入盛有无水硫酸镁、N-丙基乙二胺吸附剂(PSA)、C18吸附剂的净化管中净化,采用Hypersil Gold C18色谱柱,以不同比例的0.15%(φ)甲酸溶液和乙腈组成的混合液为流动相进行梯度洗脱。以电喷雾离子源正负离子切换多反应监测(MRM)模式进行质谱分析。7种保鲜剂的线性范围均在2.00~100μg·L~(-1)之间,测定下限(10S/N)为0.02~1.2μg·kg~(-1)。1.00,5.00,40.0μg·kg-1等3个添加水平的回收率在80.5%~120%之间,相对标准偏差(n=8)在2.8%~9.7%之间。     

液相色谱-串联质谱法测定牛奶中5种多肤类抗生素

建立了牛奶中杆菌肽、粘杆菌素A、粘杆菌素B、维吉尼霉素和万占霉素5种多肽类抗生素的反相液相色谱-串联质谱(HPLC-MS/MS)检测方法.牛奶样品经甲醇-0.1%甲酸水提取后,用4%三氯乙酸乙睛除蛋白,液-液萃取后,采用0.1%甲酸(A)和0.1%甲酸乙腈(B)作为流动相进行梯度洗脱.质谱(ESI+)采用多离子检测模式...     

液相色谱-串联质谱法检测蜂蜜中杀虫脒及其代谢产物残留

建立了液相色谱-串联质谱分析洋槐蜜、荆条蜜、蜂巢蜜、杂花蜜、野蜂蜜中杀虫脒及其代谢产物残留的方法。样品经氢氧化钠水溶液稀释溶解后,采用Waters Oasis HLB固相萃取柱净化。样品提取液经Agilent XDB-C18色谱柱分离,以0.1%甲酸水溶液和乙腈为流动相进行梯度洗脱。以电喷雾正离子(ESI+)模式电离,多反应监测(MRM)模式检测,基质匹配标准溶液外标法定量。杀虫脒及其代谢产物(4-氯邻甲苯胺)在2.5～250 μg/L范围内呈线性相关,相关系数(r)均大于0.999;定量限(S/N＞10)为5 μg/kg,检出限(S/N＞3)为2.5 μg/kg。各种蜂蜜基质样品在5、10和20 μg/kg添加水平时,杀虫脒及其代谢产物的回收率范围分别为75.8%～113.8%和85.6%～114.3%,相对标准偏差(RSD)分别为4.8%～10.2%和4.7%～9.1%,可以满足蜂蜜中杀虫脒及其代谢产物残留量的检测需要。     

液相色谱-串联质谱法测定水产品中麻醉剂MS-222残留

建立了液相色谱-串联质谱法测定水产品中麻醉剂3-氨基苯甲酸乙酯甲基磺酸盐(MS-222)残留量的方法。提取液为50%的甲醇及乙酸-乙酸钠缓冲溶液,提取液经C18固相萃取柱净化处理后用液相色谱-串联质谱仪进行测定,外标法定量。流动相为0.5%的甲酸溶液和乙腈(V:V=60:40),流速为0.2 mL/min。该方法的线性范围为0.001～1.0 mg/L,相关系数大于0.999,检出限为1μg/kg,定量限为2μg/kg。加标回收率可以达到80%～110%。     

液相色谱-串联质谱法快速筛查马饲料中39种违禁药物

建立了同时快速筛查和确证马饲料中39种赛马违禁药物(包含抗心率失常类药物、抗惊厥类药物、止痉挛类药物、抗疟疾类药物、刺激剂、麻醉剂及大麻酚类药物)的液相色谱串联质谱(HPLC-MS/MS)分析方法。样品粉碎后分别经1 mmol/L HClO4溶液和酸化乙腈溶液提取,并通过混合型固相萃取柱净化。采用Agilent Zorbax SB(10.0 cm×2.1 mm i.d.,3.5 μm) 色谱柱,以0.4%甲酸水溶液和0.4%甲酸乙腈为流动相进行梯度洗脱,正离子多反应监测(MRM) 模式下检测。方法对空白饲料3个加标水平下的平均回收率为58%~116%,相对标准偏差为1.6%~20.4%,各类药物线性良好(r2＞0.99)。方法检出限(S/N≥3)和定量下限(S/N≥10)分别为0.2~25.0 μg/kg和1.0~40.0 μg/kg,其中超过67%药物的检出限在2.5 μg/kg以下。实验结果表明,该方法分析时间短,灵敏度、精密度良好,适用于马饲料中上述几类药物的快速筛查和测定。     

Determination of clavulanic acid in calf plasma by liquid chromatography tandem mass spectrometry

A method for the quantification of clavulanic acid in calf plasma using high-performance liquid chromatography combined with electrospray ionization (ESI) mass spectrometry, operating in the negative ionization mode (LC-MS/MS), is presented. Sample preparation includes a simple and fast deproteinization with acetonitrile and a back-extraction of the acetonitrile with dichloromethane. Chromatography is performed on a reversed-phase PLRP-S polymeric column using 0.05% formic acid in water and acetonitrile. The limit of quantification is 25 ng/ml, which is lower than other published methods using ultraviolet (UV), fluorimetric or mass spectrometric detection. The limit of detection is calculated to be 3.5 ng/ml. The stability of clavulanic acid was demonstrated according to The Guidelines of Bioanalytical Method Validation of The Food and Drug Administration (FDA): freeze and thaw stability, short-term stability, long-term stability, stock solution stability and postpreparative stability. The method is used in a pharmacokinetic and bioequivalence study of amoxycillin/clavulanic acid formulations in calves.     

The use of acetone as a substitute for acetonitrile in analysis of peptides by liquid chromatography/electrospray ionization mass spectrometry

The recent worldwide shortage of acetonitrile has prompted interest in alternative solvents for liquid chromatography/mass spectrometry (LC/MS). In this work, acetone was substituted for acetonitrile in the separation of a peptide mixture by reversed‐phase high‐performance liquid chromatography (RP‐HPLC) and in the positive electrospray ionization mass spectrometry (ESI‐MS) of individual peptides. On both C12 and C18 stationary phases, the substitution of acetone for acetonitrile as the organic component of the mobile phase did not alter the gradient elution order of a five‐peptide retention standard, but did increase peak width, shorten retention times, and increase peak tailing. Positive ESI mass spectra were obtained for angiotensin I, bradykinin, [Leu⁵]‐enkephalin, and somatostatin 14 dissolved in both acetonitrile/water/formic acid (25%/75%/0.1%) and acetone/water/formic acid (25%/75%/0.1%). Under optimized ESI‐MS conditions, the mass spectral response of [Leu⁵]‐enkephalin was increased two‐fold when the solvent contained acetone. The substitution of acetone for acetonitrile resulted in only slight changes in the responses of the remaining peptides. A higher capillary voltage was required for optimum response when acetone was used. Compared with acetonitrile/water/formic acid (50/50/0.1%), more interfering species below m/z = 140 were found in the ESI‐MS spectra of acetone/water/formic acid (50/50/0.1%). Copyright © 2009 John Wiley & Sons, Ltd.     

高效液相色谱-串联质谱法测定鸡肉组织中癸氧喹酯残留

建立了测定鸡肉组织中癸氧喹酯(DEC)残留的高效液相色谱-串联质谱(HPLC-MS/MS)方法。样品经乙腈提取,正己烷脱脂,固相萃取(SPE)小柱净化;采用0.1%甲酸乙腈溶液-0.1%甲酸水溶液(78:22, v/v)为流动相,电喷雾正离子电离(ESI+)模式,多反应监测(MRM)检测模式,以内标法进行定量。结果表明: DEC在1～200 μg/L范围内呈良好的线性关系,相关系数(r2)大于0.99; 1、10、100 μg/kg 3个添加水平的回收率为78.2%～107.4%,日内、日间相对标准偏差(RSD)均小于15%,方法检出限为0.25 μg/kg,定量限为0.5 μg/kg。该方法简便、灵敏、精确,可用于鸡肉组织中DEC药物残留的确证检测。     

Simultaneous determination of flonicamid and its metabolites in vegetables using QuEChERS and reverse-phase liquid chromatography-tandem mass spectrometry

This paper presents a rapid analytical method for the simultaneous determination of flonicamid and its metabolites N-(4-trifluoromethylnicotinoyl) glycine (TFNG), 4-trifluoromethylnicotinic acid (TFNA), and 4-trifluoromethylnicotinamide (TFNA-AM) in vegetables using QuEChERS by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Samples were extracted with acetonitrile. The extract was purified through QuEChERS method with primary secondary amine (PSA) and graphite carbon black (GCB). Then the extract was diluted with 0.1% formic acid in water, and analyzed by LC-MS/MS on a Waters Acquity BEH C18 column with methanol/0.1% formic acid in water as mobile phase with gradient elution. The linearity of the analytical response across the studied range of concentrations (0.20-500 μg/L) was excellent, obtaining correlation coefficients higher than 0.998. No significant matrix effects were observed. Recovery studies were carried out on spiked spinach and cucumber blank samples, at four concentration levels (0.01, 0.05, 0.50 and 2.0 mg/kg) performing six replicates at each level. Mean recoveries of 81.3-94.8% with CVs of 2.4-7.0% were obtained. The method demonstrated to be suitable for the simultaneous determination of flonicamid and its metabolites in vegetables.     

液相色谱-串联质谱法测定蔬菜水果中的吡丙醚残留量

建立了测定蔬菜、水果中吡丙醚残留量的液相色谱-串联质谱(LC-MS/MS)分析方法。样品在醋酸钠缓冲液下用酸性乙腈提取,取1 mL提取液用PSA（N-丙基乙二胺）填料净化后,采用CAPCELL PAK C18色谱柱(50 mm×2.0 mm,3 μm)分离,以含0.1%甲酸的乙腈溶液和含0.1%甲酸的2 mmol/L乙酸铵溶液作为流动相进行梯度洗脱,以电喷雾电离三重四极杆串联质谱在正离子多反应监测(MRM)模式下进行测定。吡丙醚在2.5～50 μg/L范围内呈线性关系,相关系数为0.9999,在5,50,100 μg/kg 3个添加水平下的回收率为84.7%～91.5%,相对标准偏差(RSD,n10)低于10%。该方法操作简便,稳定性和选择性好,灵敏度高(检出限为5 μg/kg),适用于蔬菜、水果中吡丙醚残留量的测定。     

分散固相萃取结合液相色谱-串联质谱法测定饲料中8种脂溶性着色剂

建立了饲料中8种脂溶性着色剂(对位红、苏丹红Ⅰ、苏丹红Ⅱ、苏丹红Ⅲ、苏丹红Ⅳ、苏丹红7B、苏丹红G、苏丹黄)含量的液相色谱-串联质谱测定方法。饲料样品中脂溶性着色剂经乙腈提取,离心后上清液采用分散固相萃取净化,净化液稀释后进行LC-MS/MS分析。样品测定时采用Acquity BEH C18色谱柱进行色谱分离,以0.2%甲酸溶液-乙腈作为流动相进行梯度洗脱,电喷雾正离子(ESI+)模式电离,多反应监测(MRM)模式检测,同位素稀释内标法定量。8种脂溶性着色剂在1.0~200μg/L范围内线性关系良好,相关系数(r~2)均大于0.998;在饲料中的方法检出限为5.0μg/kg,定量下限为10μg/kg。在10,50,500μg/kg加标浓度下8种脂溶性着色剂的回收率为102%~111%,批内相对标准偏差(RSD)为2.8%~8.0%,批间RSD为2.8%~7.8%。该方法能满足饲料样品中脂溶性着色剂监控的需要。