固相萃取-UPLC-MS/MS快速测定猪尿中的苯乙醇胺A

建立了-种固相萃取-超高效液相色谱-串联质谱法（SPE—UPLC—MS／MS）快速测定猪尿中苯乙醇胺A的方法。猪尿样品以莱克多巴胺-D,为内标,尿液经酸化后离心,上清液经OasisMCX固相萃取柱净化,超高效液相色谱-串联质谱法测定。苯乙醇胺A监测离子为m／z345〉150和m／z 345〉327。结果表明在0．2～5μg／L范围内苯乙醇胺A呈良好的线性关系,高中低浓度绝对回收率在80—110％,精密度小于15％,最低定量限0．2μg／L。本方法快速、简便,适于猪尿中苯乙醇胺A的残留测定。     

LC-MS/MS结合定量触发相关MS/MS扫描功能同时定性确证和定量测定饲料中的违禁药物喹乙醇

本实验利用定量触发相关MS/MS扫描(QED-MS/MS)功能,建立饲料中喹乙醇的同时定性确证和定量测定LC-MS/MS方法。饲料中喹乙醇经5%甲醇-水溶液提取,Oasis HLB固相萃取柱净化后,通过LC-MS/MS分析。LC-MS/MS采用Zorbax SB C18柱(3.5μm,2.1×150 mm),0.2%乙酸-甲醇梯度洗脱,加热电喷雾离子化,选择性反应监测m/z 264>212作为定量测定,同时以数据依赖扫描模式对m/z 150～265扫描,作为定性确证结果。结果表明:本方法在0.2～10 mg/kg范围内线性关系良好,最低同时定性定量限为0.2 mg/kg。因此基于QED-MS/MS的LC-MS/MS方法可用于饲料中喹乙醇的检测。     

超高效液相色谱-串联质谱法测定原料乳和奶粉中三聚氰胺的含量

该试验建立了使用超高效液相色谱-串联四极杆质谱测定原料乳和奶粉中三聚氰胺含量的检测方法。用三氯乙酸溶液和乙酸铅提取．提取液经MCX固相萃取柱净化后用UPLC-MS-MS进行检测。色谱条件：CAPCELLPAKCRl：4柱（2．0mm×100mmi．d．,5μm）,流动相：乙腈-0．01mol／L乙酸铵溶液,梯度洗脱流速0．3ml／min。采用正离子模式的电喷雾质谱检测．以一级质谱得到的准分子离子m／z 126．8作为母离子,进行碰撞诱导解离（CID）二级质谱（MS2）分析,选择母离子和MS2的碎片离子m／z84．9、67．8定性确证,提取m／z84．9离子质量色谱峰面积定量。基质标准线性范围为0．01～1．00μg/ml,检出限10μg／kg（S／N=10）,原料乳回收率为82．4%～97．8％．奶粉回收率为80．7％～95．7％。     

超高效液相色谱-串联质谱法测定原料乳和奶粉中三聚氰胺的含量

该试验建立了使用超高效液相色谱-串联四极杆质谱测定原料乳和奶粉中三聚氰胺含量的检测方法.用三氯乙酸溶液和乙酸铅提取,提取液经MCX固相萃取柱净化后用UPLC-MS-MS进行检测.色谱条件:CAPCELL PAK CR1:4柱(2.0 mm×100 mmi.d.,5 μm),流动相:乙腈-0.01 mol/L乙酸铵溶液,梯度洗脱流速0.3ml/min.采用正离子模式的电喷雾质谱检测,以一级质谱得到的准分子离子m/z 126.8作为母离子,进行碰撞诱导解离(CID)二级质谱(MS2)分析,选择母离子和MS2的碎片离子m/z 84.9、67.8定性确证.提取m/z 84.9离子质量色谱峰面积定量.基质标准线性范围为0.01～1.00 μg/ml,检出限10 μg/kg(S/N=10),原料乳回收率为82.4%～97.8%,奶粉回收率为80.7%～95.7%.     

HPLC-ESI-MS/MS法检测N-氨甲酰谷氨酸的含量

建立了检测样品中N-氨甲酰谷氨酸含量的HPLC-ESI-MS/MS分析方法。采用负离子多反应监测方法（MRM）测试,以碎片离子m/z 147.9和m/z 83.9进行定性,以碎片离子m/z 129.9进行定量。色谱柱为Agilent Zorbx SB-C18（4.6×150 mm,5μm）柱;流动相为乙腈—0.1%甲酸水溶液（5∶95,V/V）;柱温为20℃。结果表明,N-氨甲酰谷氨酸在20.0~500.0 g/L内呈良好的线性关系,相关系数为0.999 8;精密度和准确度等均符合样品检测的要求。建立的方法准确、灵敏、特异性强,适用于样品中N-氨甲酰谷氨酸的含量检测。     

超高效液相色谱-串联质联用法筛查猪肉中66种药物残留

建立了猪肉中磺胺类、氟喹诺酮类、四环素类、大环内酯类、林可胺类、硝基咪唑类、氯霉素类、解热镇痛类、抗病毒类、镇定剂类和头孢类等11类66种药物液相色谱-串联质谱（UPLC—MS／MS）检测方法。样品经乙腈-甲醇（V/V,95：5）和乙腈-水（V/V,15：2）溶液分别提取后,Agela Cleanert@PEP-2固相萃取柱净化后采用UPLC—MS／MS测定,外标法定量。结果表明,猪肉中66药物检测限为O．2～5μg／kg,定量限为0．5-20μg/kg。在2～100μg/kg添加浓度范围内药物回收率在35％～140％之间,批内相对标准偏差均小于20％。本方法可实现对多种兽药的同时检测,为动物源性食品中药物残留监控提供快速、灵敏的分析手段,具有很重要的现实意义。     

动物源食品中氯霉素、甲砜霉素、氟苯尼考及氟苯尼考胺残留检测－超高效液相色谱-串联质谱法研究

建立了动物源食品中氯霉素、甲砜霉素、氟苯尼考及氟苯尼考胺残留检测的超高效液相色谱-串联质谱（UPLC—MS／MS）分析方法。样品在碱性条件下用乙酸乙酯提取后,再用正己烷去除脂肪,浓缩后用BEH C18（50mm×2．1mm,1．7μm）色谱柱分离,以乙腈和水为流动相进行梯度洗脱,流速为0．3mL／min,多反应监测（MRM）模式检测。结果表明：四种药物在2—500μg／L的系列浓度范围内均呈良好线性关系,相关系数r均大于0．990。样品中氯霉素的检测限为0．1μg／kg,定量限为0．2μg/kg;甲砜霉素、氟苯尼考和氟苯尼考胺的检测限为0．5μg/kg,定量限为1μg／kg。本方法氯霉素在0．2～1μg／kg的添加浓度范围内,甲砜霉素、氟苯尼考及氟苯尼考胺在1—50μg／kg的添加浓度范围内平均回收率均为70％-120％,相对标准偏差（RSD）均小于20％。该方法具有简便快捷、灵敏度高、定性准确等特点。     

液质联用法检测田七花总皂苷中人参皂苷Rb_1含量的研究

为了测定田七花总皂苷中人参皂苷Rb1的含量,试验采用HPLC-MS/MS分析方法,以BDS HYPERSUL C18(150 mm×2.1 mm,5μm)柱为色谱柱;乙腈-水(梯度洗脱)为流动相;柱温为30℃;检测模式为多反应离子监测模式(MRM),用于定量分析的对照品离子对为人参皂苷Rb1(m/z1 107.9→783.7),内标物紫杉醇(m/z 852.5→525.3)。结果表明:人参皂苷Rb1标准曲线的线性范围为0.159~16.0μg/m L,精密度和准确度等均符合样品分析要求。说明该方法准确、灵敏、特异性强,适用于田七花总皂苷及其制剂中人参皂苷Rb1浓度的检测。     

市售猪肉及其组织中"瘦肉精"残留调查

采用德国r-Biopharm拜发公司试剂盒，用竞争性EUSA法对某市13个菜场共抽取40份瘦肉、30份猪肝、18份猪肾脏、30份猪肺、15份猪骨和30份猪血、30份猪毛，总计样品进行了瘦肉精残留检测。结果表明，在抽检的193份样品中共有38份瘦肉精含量大于1．0ng／g，占总数的19．7％，其中猪肝与猪毛的检出率最高。同时在瘦肉精含量大于1．0ng／g的样品中抽取9份，用GC／MS／MS法确证，结果与ELISA法相符。     

应用酶联免疫吸附法(ELISA)结合胶体金试纸法快速筛选猪尿中的盐酸克伦特罗残留

猪尿中盐酸克伦特罗（Clenbuterol．简称CL）的残留检测，目前的检测方法．主要有高效液相色谱法（HPLC）．气相色谱-质谱法（GC/MS）．毛细管区带电泳法（CE）和酶联免疫吸附法（ELISA）等。其中GC／MS法是农业部规定的动物组织中CL确证检测方法（NY/T468-2001）．ELISA法是农业部规定的猪尿中CL筛选检测方法。GC/MS法具有灵敏、准确、特异的优点，但存在仪器贵重、操作烦琐、费用昂贵、耗费时间等问题．限制其在基层日常工作中的应用。     

Confirmation of indandione rodenticide toxicoses by mass spectrometry/mass spectrometry.

Mass spectrometry/mass spectrometry (MS/MS) with collision-activated dissociation (CAD) was utilized to unequivocally distinguish 1,3-indandione rodenticides in 2 cases of anticoagulant toxicosis. Anecdotal evidence provided by the veterinarian in a case involving feedlot cows and physical evidence at the site of occurrence in a similar case involving lambs strongly implicated diphenadione (diphacinone; DP) in both instances. However, high performance liquid chromatography indicated chlorophacinone (CP), not DP, was present in the blood samples obtained from both cows and lambs. Intact 1,3-indandiones exhibit poor gas chromatographic properties, so procedures were developed for analysis by MS/MS using a direct exposure probe for sample introduction. The EI mass spectra of DP and CP contained a base peak at m/z 173, with molecular ions (M+) at m/z 340 and m/z 374 (Cl isotope cluster), respectively. Corresponding MS/MS CAD parent ion spectra of m/z 173 showed an ion of m/z 340 for DP and 374 (Cl cluster) for CP. CAD analysis of the blood extracts showed a parent ion scan of m/z 173 identical to that of CP, with the m/z 374 (Cl cluster). (Additional evidence was obtained by MS/MS examination of the CAD daughter ion spectrum of m/z 374.) Blood extracts from the affected animals revealed CAD daughter ion spectra for m/z 374 identical to that of reference CP. Positive confirmation of CP in both cases led to identification of the source of the toxicant and prevention of further animal exposures.     

Direct MS-MS identification of isoxsuprine-glucuronide in post-administration equine urine.

Isoxsuprine is routinely recovered from enzymatically-hydrolyzed, post-administration urine samples as parent isoxsuprine in equine forensic science. However, the specific identity of the material in horse urine from which isoxsuprine is recovered has never been established, although it has long been assumed to be a glucuronide conjugate (or conjugates) of isoxsuprine. Using ESI/MS/MS positive mode as an analytical tool, urine samples collected 4-8 h after isoxsuprine administration yielded a major peak at m/z 554 that was absent from control samples and resisted fragmentation to daughter ions. Titration of this material with increasing concentrations of sodium acetate yielded m/z peaks consistent with the presence of monosodium and disodium isoxsuprine-glucuronide complexes, suggesting that the starting material was a dipotassium-isoxsuprine-glucuronide complex. Electrospray ionization mass spectrometry negative mode disclosed the presence of a m/z 476 peak that declined following enzymatic hydrolysis and resulted in the concomitant appearance of peaks at m/z 300 and 175. The resulting peaks were consistent with the presence of isoxsuprine (m/z 300) and a glucuronic acid residue (m/z 175). Examination of the daughter ion spectrum of this putative isoxsuprine-glucuronide m/z 476 peak showed overlap of many peaks with those of similar spectra of authentic morphine-3- and morphine-6-glucuronides, suggesting they were derived from glucuronic acid conjugation. These data suggest that isoxsuprine occurs in post-administration urine samples as an isoxsuprine-glucuronide conjugate and also, under some circumstances, as an isoxsuprine-glucuronide-dipotassium complex.     

Identification of hydroxyropivacaine glucuronide in equine urine by ESI+/MS/MS.

Ropivacaine is a local anesthetic that has a high potential for abuse in racing horses. It can be recovered from urine collected after administration as a hydroxylated metabolite following beta-glucuronidase treatment of the urine. Based on these findings, it has been inferred that ropivacaine is present in equine urine as a glucuronide metabolite; however, these metabolites have never been directly identified. Using ESI+/MS/MS, the presence of a [M+H]+ molecular ion of m/z 467 was demonstrated in urine corresponding to the calculated mass of a hydroxyropivacaine glucuronide +1. The abundance of this ion diminished after glucuronidase treatment with concomitant appearance of a m/z 291 peak, which is consistent with its hydrolysis to hydroxyropivacaine. In further work, the m/z 467 material was fragmented in the MS/MS system, yielding fragments interpretable as hydroxyropivacaine glucuronide. These data are consistent with the presence of a hydroxyropivacaine glucuronide in equine urine and constitute the first direct demonstration of a specific glucuronide metabolite in equine urine.     

The metabolite products of chlorocholine chloride (CCC) in eggs and meat of laying hens fed 15N-CCC containing diets

An experiment was conducted to evaluate the metabolic products of chlorocholine chloride (CCC) in eggs and meat of laying hens fed a diet containing (15)N-CCC. Ten brown laying hens were randomly divided into two groups of five each. One group was offered (15)N-CCC free diet while the other group received a diet with 100 ppm (15)N-CCC for 11 days. Samples of eggs and meat from the laying hens were collected. Egg yolks and albumen were separated. Meat was collected from the breast and femur. The metabolic products of CCC were measured using ion trap electrospray ionisation mass spectrometry (ion trap-ESI-MS/MS). Determination of CCC or its metabolites in eggs and meat showed that CCC was metabolised to choline. Corresponding MS/MS spectra were obtained for m/z 104 (choline) or 105 ((15)N-choline), whereas nothing was detected at m/z 122 (CCC) or 123 ((15)N-CCC). The results from this study indicate that CCC will be metabolised in tissues of laying hens.     

Identification of lidocaine and its metabolites in post-administration equine urine by ELISA and MS/MS

Lidocaine is a local anesthetic drug that is widely used in equine medicine. It has the advantage of giving good local anesthesia and a longer duration of action than procaine. Although approved for use in horses in training by the American Association of Equine Practitioners (AAEP), lidocaine is also an Association of Racing Commissioners International (ARCI) Class 2 drug and its detection in forensic samples can result in significant penalties. Lidocaine was observed as a monoprotonated ion at m/z 235 by ESI+ MS/MS (electrospray ionization-positive ion mode) analysis. The base peak ion at m/z 86, representing the postulated methylenediethylamino fragment [CH2N(CH2CH3)2]+, was characteristic of lidocaine and 3-hydroxylidocaine in both ESI+ and EI (electron impact-positive ion mode) mass spectrometry. In addition, we identified an ion at m/z 427 as the principal parent ion of the ion at m/z 86, consistent with the presence of a protonated analog of 3-hydroxylidocaine-glucuronide. We also sought to establish post-administration ELISA-based 'detection times' for lidocaine and lidocaine-related compounds in urine following single subcutaneous injections of various doses (10, 40, 400 mg). Our findings suggest relatively long ELISA based 'detection times' for lidocaine following higher doses of this drug.     

Gas chromatography/mass spectrometry identification and quantification of isazophos in a famphur pour-on and in bovine tissues after a toxic exposure.

A sample identified as "Warbex pour-on," expected to contain 13.2% famphur, and bovine tissue samples from 2 heifers that died after exhibiting signs of organophosphate intoxication were analyzed by gas chromatography/mass spectrometry (GC/MS). A product formulation problem was suspected because brain cholinesterase activities were depressed in both animals. Electron impact (EI) GC/MS of the pour-on revealed 9.7% famphur and an unidentified peak with approximately 76% of the peak area of the famphur. The unidentified peak showed a molecular ion at m/z 313, with a single Cl isotope cluster. Methane chemical ionization (MeCI) MS confirmed the molecular weight at 313 (1 Cl). A search on the molecular formula C9H17N3O3PSCl yielded a single match, isazophos. EI and MeCI GC/MS of reference isazophos confirmed the identity of the suspect peak. The concentration of isazophos in the pour-on was determined to be 6.0%. Famphur and isazophos were identified by their EI spectra and GC retention times in extracts of liver and brain from the 2 deceased animals. A GC/MS procedure utilizing selected ion monitoring (SIM) was developed for quantification of isazophos in liver, kidney, muscle, and fat of additional affected animals sacrificed at various times after exposure. Isazophos remained in animal tissues for as long as 94 days after topical exposure. Isazophos was present in fetal liver 70 days after exposure of the dam. High levels (6-3,500 ppm) of isazophos and famphur remained on the skin at 39 days postexposure.     

气相色谱-质谱法测定鸡蛋中三聚氰胺残留

采用气相色谱-质谱法(GC-MS)测定了鸡蛋中三聚氰胺残留。样品匀浆后,用三氯乙酸去蛋白提取,MCX柱净化,BSTFA和TMCS衍生化后,气相色谱-质谱检测。质谱定性离子为m/z342、327、171和99,定量离子为m/z327。方法定量限为0.5μg/g,添加浓度为0.5、2μg/g和10μg/g时的回收率在89.2%~96.2%之间,变异系数在2.9%~5.6%之间。     

液相色谱-质谱联用法研究青蒿素在鸡体内的代谢规律

为探究青蒿素（ART）在鸡体内的代谢规律,本研究建立了液相色谱串联三重四级杆质谱检测鸡血浆中ART的方法：即以电喷雾电离源（ESI）作为离子源,以蒿甲醚（ARM）做内标（IS）,以ART和ARM的[M+Na]⁺准离子峰做二级质谱扫描,选择m/z 305.2 → 151.3（ART）、m/z 321.0 → 163.1（ARM）两对离子以多监测反应方式（MRM）进行定量分析。结果表明,ART在10~1 000 ng/mL范围内线性关系良好（R²=0.9997）,最低检测限为10 ng/mL,回收率在90%~105%之间,日间、日内精密度（RSD）均小于15%。选取30日龄蛋鸡,按照3个剂量（15、40、100 mg/kg）以及口服的次数（1、11次）分成6个组,每组6只,各组分别灌胃给药。给药1次的各组前10次先口服溶剂,第11次按剂量灌服ART,给药11次的各组按剂量换算给药。每组在最后1次给药结束后10、30 min及1、1.5、2、2.5、3、4、6、8 h分别采集300 μL血液加入抗凝管中待测。经检测发现,单一剂量（15、40或100 mg/kg）口服给药后ART在鸡血浆中的达峰时间分别为1、1.5、1.5 h;但上述剂量连续多次给药后检测发现药物代谢明显加快,并有剂量依赖性。综合试验结果,本试验建立的ART检测方法操作简单,灵敏,重现性好,可用于鸡血浆中ART的检测;ART在禽类体内存在明显的自身诱导代谢现象,且剂量越高,其代谢速度越快。     

Pharmacokinetics of parenteral and oral sustained-release morphine sulphate in dogs

The pharmacokinetics of single-dose morphine sulphate (MS) administered intravenously (i.v.) and intramuscularly (i.m.) and of oral sustained-release morphine sulphate (OSRMS) were studied in dogs. Beagles (n = 6) were randomly assigned to six treatment groups using a Latin square design. Treatments included MS 0.5 and 0.8 mg/kg i.v. and i.m. and OSRMS 15 and 30 mg orally (p.o). Serum samples were drawn at intervals up to 420 min following parenteral MS and 720 min following OSRMS. Serum was analysed for morphine concentration using a radioimmunoassay . Pharmacokinetic analysis of the results revealed that MS was eliminated by a first-order process best described by a two-compartment model. For i.v. and i.m. data there were no statistically significant differences (P c 0.0 5) between steady-state volume of distribution, half-life of elimination and plasma clearance. As expected, area under the concentration vs. time curve (AUC) was significantly greater for the 0.8 mg/kg dosage for i.v. and i.m. routes, and time to maximum serum concentration was significantly longer following i.m. administration. For OSRMS there were no significant differences between dosage for any parameter (AUC, C_max. t_max t_½ F) and prolonged absorption of the drug occurred over approximately 6 h. Bioavailability (F) for both oral dosages was approximately 20%. The i.m. route is an effective method for rapid and complete delivery of MS to dogs. OSRMS may be useful in the provision of long-term analgesic therapy in dogs, but further work is required to verify the safety and effectiveness of this preparation.