高效液相-串联质谱法同时检测鸡蛋中金刚烷胺与四种氟喹诺酮类药物残留的研究

试验建立了可同时测定鸡蛋中金刚烷胺、环丙沙星、恩诺沙星、达氟沙星和沙拉沙星残留量的高效液相-串联质谱法(HPLC-MS/MS)。样品经1%甲酸乙腈提取、氮吹浓缩、复溶、正己烷脱脂净化等步骤处理后,用HPLC-MS/MS检测。结果表明:5种药物在1~50μg/L浓度范围内具有良好的线性关系,空白样品同时添加5种药物的回收率均在76.6%~102.1%之间;定量限为1μg/kg,检出限为0.5μg/kg。该方法操作简单、快速、灵敏、高效。     

鸡蛋中氟喹诺酮类药物残留量检测方法研究

建立一种可同时检测鸡蛋中四种氟喹诺酮类药物(环丙沙星、达氟沙星、恩诺沙星和沙拉沙星)残留的高效液相色谱-荧光检测法。结果表明,四种氟喹诺酮类药物中环丙沙星、恩诺沙星、沙拉沙星在2~500 ng/mL范围内峰面积与浓度呈良好的线性关系,R2均大于0.9999;达氟沙星在0.4~100 ng/mL范围内峰面积与浓度呈良好的线性关系,R2大于0.9999。环丙沙星、恩诺沙星、沙拉沙星的定量限为10μg/kg,达氟沙星的定量限为2μg/kg。环丙沙星、恩诺沙星、沙拉沙星在10~200μg/kg的浓度添加水平上,其回收率为70%~100%;达氟沙星在2~40μg/kg的浓度添加水平上,其回收率为70%~100%,批内、批间的相对标准偏差均小于10%。     

高效液相色谱-串联质谱法检测鸡蛋和鸡组织中恩诺沙星、环丙沙星残留的研究

为建立一种高效液相色谱-串联质谱法检测鸡蛋和鸡组织(肝脏、肾脏、肌肉、脂肪)中恩诺沙星、环丙沙星的残留,鸡蛋和鸡组织(肝脏、肾脏、肌肉、脂肪)经酸化乙腈提取,正己烷除脂净化,以0.1%甲酸水溶液和乙腈为流动相进行梯度洗脱,同位素内标法定量。结果显示:恩诺沙星、环丙沙星均在线性范围内呈现良好线性关系,相关系数(R2)均大于0.99;恩诺沙星、环丙沙星在组织中的检测限为1μg/kg,定量限为5μg/kg;两种药物的平均回收率范围为75.5%～106%,批内、批间变异系数均小于11.2%。研究表明,该方法样品前处理简单,灵敏度高,适用同时检测鸡组织(肝脏、肾脏、肌肉、脂肪)和鸡蛋中恩诺沙星、环丙沙星残留。     

液质联用法检测禽蛋中氟苯尼考和氟苯尼考胺残留

建立了超高效液相色谱串联质谱法检测禽蛋中氟苯尼考和氟苯尼考胺残留物的方法。采用电喷雾离子源（ESI）、多反应监测（MRM）、正负离子模式同时扫描检测,内标法定量。禽蛋试样采用碱化乙酸乙酯和乙腈提取,正己烷萃取,LC/MS-MS分析。结果表明,该方法的检测限（LODs）为0.1 μg/kg,定量限（LOQs）为0.2 μg/kg。在0.2~200 μg/L范围内均呈良好线性关系,并且3个添加浓度的平均回收率范围为70%~110%,相对标准偏差（RSD）小于10%。该方法简便高效、准确可靠,可作为禽蛋中氟苯尼考和氟苯尼考胺残留的检测方法。     

荧光定量技术检测牛奶中四环素类药物残留准确性的研究与探讨

以四环素为对照物建立标准曲线,得出该药物最低检出限为4.93 μg/L。为保障产品的稳定性,可认为四环素类荧光定量检测卡在生鲜乳中的检测限为5.00 μg/L。样品各添加浓度的回收率均在84.60%~113.94%,各添加浓度的批内、批间变异系数均低于15.00%。四环素类荧光定量检测卡检测为阳性和仪器法检测为阳性的符合率为100.00%。     

基于HPLC-MS/MS的鸡蛋中59种残留杀虫剂的测定

研究建立了高效液相色谱-串联质谱法(HPLC-MS/MS)测定鸡蛋中的59种残留杀虫剂的方法。经乙腈提取,过SinCHERS萃取柱净化,进HPLC-MS/MS检测,通过电喷雾正负离子扫描模式对59种杀虫剂残留同时进行鉴定与定量分析。结果表明,该方法的标准工作曲线线性良好,相关系数均大于0.9900,回收率均在60%～120%之间,相对标准偏差(RSD)为1.2%～15.0%,方法的检出限为0.5～2.0μg/kg,定量限为2.0～10.0μg/kg。该方法前处理简便、可靠、灵敏度高,可适用于鸡蛋中多种杀虫剂残留的测定。     

化学发光免疫试剂盒检测猪肉中呋喃西林代谢物的残留

为了快速检测猪肉中呋喃西林代谢物残留量,试验采用自主研发的以磁性微球为固定相的化学发光免疫试剂盒,并对其方法学进行评价及与高效液相色谱-串联质谱法(HPLC-MS/MS法)检测结果进行比较分析。结果表明:采用化学发光免疫试剂盒测定猪肉中呋喃西林代谢物的灵敏度为0.331μg/kg,精密度较好,最低检测限为0.077μg/kg,与呋喃西林原药的交叉反应率为8.9%,与其他类似物的交叉反应率均0.1%,平均回收率为92.7%~104.8%,与HPLC-MS/MS法检测样本的阴性和阳性结果一致。说明该试剂盒具有灵敏度高、特异性强、检测速度快等特点,适用于现场快速检测猪肉中呋喃西林代谢物的残留。     

新型反相固相萃取吸附剂测定鸡蛋中4种氟喹诺酮类药物残留量

建立了一种使用新型反相固相萃取吸附剂(PRiME HLB)的前处理净化流程,采用高效液相色谱-荧光检测器同时测定鸡蛋中环丙沙星、达氟沙星、恩诺沙星和沙拉沙星残留量的方法。试样经乙腈∶0.2%甲酸水溶液(80∶20)提取,PRiME HLB固相萃取柱净化后进行测定,外标法定量。实验结果表明:(1)在鸡蛋中环丙沙星、恩诺沙星和沙拉沙星的检测限为0.75μg/kg,达氟沙星的检测限为0.15μg/kg;在0.005~0.5μg/mL质量浓度范围(达氟沙星在0.001~0.2μg/mL浓度范围)内线性回归关系良好(r0.99999)。(2)环丙沙星、恩诺沙星和沙拉沙星的添加量为0.005、0.05、0.5μg/mL(达氟沙星0.001、0.02、0.2μg/mL)时,方法的添加回收率在74.24%~98.78%,RSD5.15%。本方法适用于鸡蛋中4种氟喹诺酮类药物残留量的测定。     

液相色谱-串联质谱法测定鸡蛋中7种氟喹诺酮类药物的残留量

建立了一种液相色谱-串联质谱法测定鸡蛋中7种氟喹诺酮类药物残留的方法。样品经EDTA-Mcllvaine缓冲液提取,冷冻离心,然后用正己烷脱脂,有效地去除杂质,HLB固相萃取柱净化,氮气吹干浓缩,流动相溶解,进行LC-MS/MS定性定量分析。其中5种氟喹诺酮类药物含量在2.5μg/kg~100μg/kg范围内,线性关系良好,环丙沙星和恶喹酸含量分别在6μg/kg~240μg/kg和0.25μg/kg~10μg/kg范围内,线性关系良好,相关系数均大于0.995 9;添加量在100、200、500μg/kg时,该方法的加标回收率为36.9%~81.2%,相对标准偏差均小于15.8%。该方法对环丙沙星和恶喹酸的检测限分别为1.2μg/kg和0.05μg/kg,定量限为24μg/kg和1μg/kg,其他5种氟喹诺酮类药物的检测限为0.5μg/kg,定量限为10μg/kg,表明所建立的方法适用于鸡蛋中7种氟喹诺酮类药物残留的定性和定量检测。     

高效液相色谱-串联质谱法研究猪毛发中克仑特罗和莱克多巴胺的残留及代谢规律

建立了高效液相色谱-串联质谱(HPLC-MS/MS)同时检测猪毛发中克仑特罗和莱克多巴胺残留的方法。猪毛发经1 mol/L氢氧化钠溶液水解、乙酸乙酯萃取、MCX固相萃取柱净化,流动相溶解后用HPLC-MS/MS进行检测。克仑特罗在1.9～463.2 ng/mL浓度范围内线性关系良好(R2=0.999 0);回收率为83.3%～86.6%,相对标准偏差为6.7%～9.2%;检出限为0.3μg/kg,定量限为0.8μg/kg。莱克多巴胺在2.8～562.9 ng/mL浓度范围内线性关系良好(R2=0.999 2);回收率为83.4%～88.4%,相对标准偏差为7.2%～9.6%;检出限为0.4μg/kg,定量限为1.2μg/kg。应用该方法研究了克仑特罗、莱克多巴胺在猪毛发中的代谢规律并进行了猪毛发样品检测。结果喂药7 d至停药21 d猪毛发中均检出克仑特罗、莱克多巴胺残留;检测猪毛发样品25份,1份样品检出克仑特罗,残留量为58.68μg/kg。     

Population pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin in chicken based on retrospective data, incorporating first-pass metabolism

Guo, Q.-J., Huang, L.-L., Fang, K., Wang, Y.-L., Chen, D.-M., Tao, Y.-F., Dai, M.-H., Liu, Z.-L., Peng, D.-P., Yuan, Z.-H. Population pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin in chicken based on retrospective data, incorporating first-pass metabolism. J. vet. Pharmacol. Therap . 33 , 84–94.
A population pharmacokinetic (PPK) model for enrofloxacin and its metabolite ciprofloxacin in chicken based on retrospective data was developed. Plasma concentrations of enrofloxacin and its metabolite ciprofloxacin were determined in blood samples from chicken administered either enrofloxacin via oral and intravenous routes or ciprofloxacin via intravenous injection. The disposition of enrofloxacin and ciprofloxacin was described simultaneously by an integrated mathematic model. Two compartments were used to describe the enrofloxacin and ciprofloxacin disposition profiles. The formation of ciprofloxacin was through the central compartment of enrofloxacin. The integrated model was estimated with nonlinear mixed effects model (NONMEM). The total clearance of enrofloxacin (CLEN) and ciprofloxacin (CLCP) was 0.613 L/h and 1.15 L/h, respectively. Correlation between CLEN, the central compartment volume of distribution for enrofloxacin (V2) and CLCP was estimated. After intravenous administration of enrofloxacin, the transformation rate of enrofloxacin to ciprofloxacin was 0.429 L/h. The bioavailability factor after oral administration was 0.926, and 12.6% of enrofloxacin after oral administration was transformed to ciprofloxacin via first-pass effect. Pharmacodynamic (PD) evaluation was performed using area under concentration time curve of active moiety from 0 to 24 h and MIC collected from literature. This study is the first one to use PPK method to investigate parent drug and its metabolite disposition and PDs using an integrated model in veterinary medicine.     

杆菌肽在动物可食性组织和禽蛋中残留的HPLC-MS/MS检测方法

建立动物(猪、鸡、鸭)可食性组织(肌肉、肝脏、肾脏、脂肪)和禽蛋(鸡蛋、鸭蛋)中杆菌肽的高效液相色谱串联质谱(HPLC-MS/MS)检测方法.使用0.1％甲酸水溶液提取样品中的杆菌肽,三氯乙酸乙腈沉淀蛋白,正己烷除脂,混合阳离子型固相萃取柱净化后,进HPLC-MS/MS检测.待测物使用C18色谱柱分离,以0.1％甲酸水...     

Excretion pattern of enrofloxacin after oral treatment of chicken broilers

The metabolism and excretion of enrofloxacin were studied when applied as oral solution to chicken broilers for five consecutive days. Sixty 9‐day‐old broilers were isolated within an intensively rearing poultry farm during enrofloxacin therapy (15.5 mg/kg per day). The excreta of the isolated broilers were collected daily, 9 days after therapy termination, for 13 consecutive days, and analyzed for the presence of enrofloxacin and its metabolites [ciprofloxacin, desethylene‐enrofloxacin (DES‐EF) and desethylene‐ciprofloxacin (DES‐CF)]. Enrofloxacin was excreted predominantly in the form of the parent compound between days 1 and 13. Ciprofloxacin was detected in the excreta between days 1 and 6, whereas minor amounts of DES‐EF and DES‐CF were excreted only between days 1–7 and 1–6, respectively. In conclusion, the analysis of the excreta showed that approximately 74% of orally applied enrofloxacin was excreted as the parent compound, approximately 25% as the main metabolite ciprofloxacin, and approximately 1% as the minor metabolites desethylene‐enrofloxacin and desethylene‐ciprofloxacin.     

Analysis of fluoroquinolone residues in edible chicken tissues using supercritical fluid extraction

We evaluated a procedure that uses high-performance liquid chromatography to determine the levels of four fluoroquinolones (ciprofloxacin, enrofloxacin, norfloxacin, and ofloxacin) remaining in chicken breast muscle, liver, and kidneys after the analytes are extracted using supercritical fluid extraction (SFE). These antimicrobial fluoroquinolones were extracted by SFE using supercritical CO2 containing 30% (v/v) methanol. The recovery, limit of detection, accuracy, and precision of this method were evaluated on the basis of fortified matrices at concentrations of 25 to 250 microg/kg. The method is validated and shown to be linear in the range of 2.5-50 microg/kg. Spike recoveries for muscle, liver and kidney samples prepared at 4 spiking levels were ranged from 56.6-104.3%, 51.2-98.4% and 62.2-97.8%, respectively. The coefficient of variation (CV) for recovery as a measure of relative variability was between 3% and 13%, and the relative standard deviation (RSD) was < 20%. The limits of quantitation (LOQ) were 10 microg/kg for enrofloxacin, 12.5 microg/kg each for ciprofloxacin and norfloxacin and 25 microg/kg for ofloxacin; these values were lower than the maximum residue levels (MRLs) authorized by the European Community. The 4 compounds were evaluated simultaneously, and the method was shown to be applicable for analyzing their residues in edible chicken tissues.     

高效液相-串联质谱法测定鸡肉中泰妙菌素残留的研究

建立了固相萃取-高效液相色谱-串联质谱法测定鸡肉中泰妙菌素残留的分析方法。试样经磷酸盐缓冲液(pH8.0)-乙酸乙酯混合提取,经水饱和正己烷除脂后,过MCX固相萃取小柱净化,采用HPLC-MS/MS电喷雾电离正离子扫描,多反应监测模式(MRM)检测,内标法定量。泰妙菌素在0.5~50μg/L的浓度范围内呈现良好的线性关系,相关系数R2大于0.999。其检测限为0.25μg/kg,定量限为0.5μg/kg。     

羊肉中多黏菌素A和多黏菌素B液相色谱—串联质谱检测方法的建立

[目的] 建立一种液相色谱—串联质谱同步测定羊肉中多黏菌素A和多黏菌素B的方法。[方法] 样品经10%三氯乙酸水溶液—乙腈溶液提取,WCX固相萃取柱净化,0.1%甲酸水溶液作为流动相进行梯度洗脱,流速0.30 mL/min,多反应监测（MRM）正离子模式扫描,用液相色谱—串联质谱仪检测,基质添加标准溶液外标法定量。[结果] 多黏菌素A和多黏菌素B在5.0~110.0 μg/L浓度范围内呈良好线性关系,线性相关系数R>0.996,方法的定量限为0.50 μg/kg,3个添加水平的平均回收率为73.2%~115.6%,RSD≤10.0%。[结论] 该方法高效、准确,适用于羊肉样品中多黏菌素A和多黏菌素B的定量及确证检测。     

Pharmacokinetic variables and tissue residues of enrofloxacin and ciprofloxacin in healthy pigs

OBJECTIVES: To determine pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin after a single i.v. and i.m. administration of enrofloxacin and tissue residues after serial daily i.m. administration of enrofloxacin in pigs. ANIMALS: 20 healthy male pigs. PROCEDURE: 8 pigs were used in a crossover design to investigate pharmacokinetics of enrofloxacin after a single i.v. and i.m. administration (2.5 mg/kg of body weight). Twelve pigs were used to study tissue residues; they were given daily doses of enrofloxacin (2.5 mg/kg, i.m. for 3 days). Plasma and tissue concentrations of enrofloxacin and ciprofloxacin were determined. Residues of enrofloxacin and ciprofloxacin were measured in fat, kidney, liver, and muscle. RESULTS: Mean (+/-SD) elimination half-life and mean residence time of enrofloxacin in plasma were 9.64+/-1.49 and 12.77+/-2.15 hours, respectively, after i.v. administration and 12.06+/-0.68 and 17.15+/-1.04 hours, respectively, after i.m. administration. Half-life at alpha phase of enrofloxacin was 0.23+/-0.05 and 1.94+/-0.70 hours for i.v. and i.m. administration, respectively. Maximal plasma concentration was 1.17 +/-0.23 microg/ml, and interval from injection until maximum concentration was 1.81+/-0.23 hours. Renal and hepatic concentrations of enrofloxacin (0.012 to 0.017 microg/g) persisted for 10 days; however, at that time, ciprofloxacin residues were not detected in other tissues. CONCLUSIONS AND CLINICAL RELEVANCE: Enrofloxacin administered i.m. at a dosage of 2.5 mg/kg for 3 successive days, with a withdrawal time of 10 days, resulted in a sum of concentrations of enrofloxacin and ciprofloxacin that were less than the European Union maximal residue limit of 30 ng/g in edible tissues.     

Comparative pharmacokinetics of enrofloxacin and ciprofloxacin in lactating dairy cows and beef steers following intravenous administration of enrofloxacin

The comparative pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin were investigated in lactating cows and beef steers. The plasma elimination half-life of either enrofloxacin or ciprofloxacin was shorter in cows than in steers. The overall production of ciprofloxacin was slightly higher in steers than in cows (metabolite ratio: 64% and 59%, respectively). There was no significant difference in plasma protein binding of enrofloxacin between cows (percent bound: 59.4%) and steers (percent bound: 60.8%). Ciprofloxacin was more extensively bound to plasma proteins in steers (percent bound: 49.6%) than in cows (percent bound: 33.8%). The steady state volume of distribution of enrofloxacin is comparable in cows (1.55 L/kg) and steers (1.59 L/kg). Within either bovine class, plasma elimination half-life of enrofloxacin and ciprofloxacin are comparable, while plasma protein binding was higher for enrofloxacin than for ciprofloxacin. Ciprofloxacin was more concentrated in milk than enrofloxacin.