喹烯酮及其主要代谢物在猪体内的药动学研究

本试验旨在研究喹烯酮及其主要代谢物在猪体内的药物代谢动力学过程。将喹烯酮按40 mg/kg的剂量对7头猪进行灌胃给药,采用HPLC-MS/MS法测定血浆中喹烯酮及其主要代谢物的浓度,药代动力学软件WinNonlin 5.2处理血浆中药物浓度－时间数据。灌胃给药后猪血浆中能检测到原药和N1-脱氧喹烯酮、脱二氧喹烯酮及3-甲基喹噁啉-2-羧酸(MQCA)3种代谢物。喹烯酮的浓度－时间数据符合一级吸收一室开放模型,其主要药代动力学参数为:T_1/2Ka＝(0.97±0.08)h,T_1/2λz＝(2.79±0.16)h,CL＝(26.03±0.65)L/h·kg,Cmax＝(0.26±0.01)μg/mL,Tmax＝(2.23±0.06)h,AUC＝(1.54±0.04)h·μg/mL;采用统计矩法处理N1-脱氧喹烯酮和脱二氧喹烯酮的浓度－时间数据,N1-脱氧喹烯酮主要药代动力学参数为:Tmax＝(6.33±1.37)h,Cmax＝(8.81±2.08) ng/mL,T_1/2λz＝(3.03±1.27)h,AUC＝(0.07±0.01)h·ng/mL,MRT＝(6.58±0.40)h;脱二氧喹烯酮的主要药动学参数:Tmax＝(10.29±0.29)h,Cmax＝(6.20±1.11)ng/mL,T_1/2λz＝(5.84±2.78)h,AUC＝(0.15±0.01)h·ng/mL,MRT＝(3.64±0.72)h。同时,在少数时间点检测到代谢物MQCA。猪口服喹烯酮后,吸收较快,消除较慢。血浆中检测到N1-脱氧喹烯酮、脱二氧喹烯酮及3-甲基喹噁啉-2-羧酸3种代谢物,且浓度较低、消除缓慢。     

超高效液相色谱-质谱法测定血浆和尿样地西泮

采用超高效液相色谱串联质谱联用仪分析猪血浆和尿液中的地西泮.血浆和尿液先经过β-盐酸葡萄糖醛苷酶水解,然后用乙酸乙酯振荡提取酶解液,分离上层有机溶剂蒸干,用乙腈溶解残渣,取上清液过滤后用LC-MS/MS进行检测.通过对提取方式和液相色谱分离条件的优化,建立猪尿和血浆中地西泮的LC-MS/MS检测方法.该方法中空白样品的加标回收率为81.6 %～105.4 %,RSD为3.8 %～13.6 %,检出限为0.5 μg/L.     

喹乙醇代谢残留标识物3-甲基喹恶啉-2-羧酸检测方法的优化

建立鸡肉中喹乙醇代谢标识物3-甲基喹恶啉-2-羧酸(MQCA)的高效液相色谱-串联四级杆质谱(UPLC-MS/MS)残留分析方法。样本在一定温度下酶解、盐酸酸化后,用酸乙酯提取,吹干浓缩后再用0.1%甲酸水溶液+乙腈(V∶V=1∶9)溶解,加入正已烷除杂;以0.1%甲酸水溶液-乙腈为流动相,经C18柱分离,采用多反应监测(MRM)正离子模式进行检测。实验结果表明,MQCA提取效果好,检出限为0.05μg/kg,在0.5μg/kg~5.0μg/kg添加水平的平均回收率在73.72%~95.22%之间,相对标准偏差为1.27%~2.79%。本方法适用于鸡肉组织中喹乙醇代谢物残留检测。     

高效液相色谱-串联质谱法检测动物血清、尿液中硝基呋喃代谢物残留

本试验旨在建立动物血清、尿液样品中硝基呋喃代谢物的高效液相色谱-串联质谱检测方法。样品在酸性条件下与2-硝基苯甲醛发生衍生化反应,经乙酸乙酯提取,采用液相色谱-串联质谱仪器进行检测。结果表明:呋喃西林代谢物、呋喃唑酮代谢物、呋喃他酮代谢物、呋喃妥因代谢物在牛血清、猪血清、鸡血清、牛尿和猪尿中的定量限均为1.0μg/kg,平均回收率为80.6%~103.9%,相对标准偏差小于15%(n=6)。该方法灵敏度高,前处理步骤简单,可适用于动物血清、尿液样品中硝基呋喃代谢物含量的检测。     

超高效液相色谱-串联质谱法测定鸡蛋中氯霉素的两种前处理方法比较

为选择氯霉素超高效液相色谱串联质谱分析前处理方法,分别对乙酸乙酯提取,正己烷液液萃取净化和乙腈提取,LC-Si固相萃取柱萃取净化(GB/T22338-2008方法),两种前处理方法进行对比分析。结果显示:乙酸乙酯提取法的检测限为0.1μg/kg,在0.5~10ng/mL范围内线性关系良好,r>0.99,回收率为98.2%~104.8%,RSD为1.5%~7.2%;乙腈提取法的检测限为0.05μg/kg,在0.25~10ng/mL范围内线性关系良好,r>0.995,回收率为100.0%~104.0%%,RSD值为0.5%~2.1%。结果表明:两种方法的线性范围、回收率、检测限和相对偏差均能满足畜产品检验要求。乙酸乙酯提取法步骤简单,样品处理效率高,乙腈提取法虽步骤繁琐,但结果的精密度和灵敏度更高。     

高效液相色谱法测定猪血浆及组织中喹赛多及其脱二氧代谢物

建立了测定猪血浆及肝脏、肾脏、肌肉等组织中的喹赛多及其代谢物脱二氧喹赛多的高效液相色谱(HPLC)法.血浆样用甲醇沉淀蛋白后离心取上清液进样测定.组织样先用乙腈匀浆,用正己烷脱脂后作HPLC检测.色谱柱为ODS C18柱;流动相血浆样测定为乙腈水(2080),组织样测定为甲醇水(4258),流速为1.0 mL/min;紫外检测波长305 nm.药物工作液质量浓度范围为0.005～0.500 mg/L时,血浆样品及组织样品测定条件下药物质量浓度与响应值均具良好线性关系,相关系数＞0.999.血浆中药物质量浓度为0.02、0.10、0.50 mg/L时,喹赛多及脱二氧喹赛多的回收率均大于70%,组织中药物含量为0.05、0.20、1.00μg/g时,肌肉样品的回收率均大于70%,肝脏、肾脏样品则为50%～80%.本试验条件下,喹赛多及其脱二氧代谢物的最低检出质量浓度,血浆样品分别为0.01、0.02mg/L,组织样品2种检测物均为0.025μg/g.测定了工作液3种质量浓度0.01、0.05、0.25 mg/L的仪器精密度,日内相对偏差＜8.0%,日间相对偏差＜17.0%.     

液相色谱-串联质谱法测定猪血浆和尿液中8种同化激素的残留

为建立猪血浆和尿液中8种同化激素的液相色谱-串联质谱(LC-MS/MS)检测方法,样品酶解后,用乙酸乙酯超声提取,经C18固相萃取小柱净化,进行LC-MS/MS检测。结果表明,采用基质添加标准曲线消除基质干扰,8种同化激素在1.5μg/L~100μg/L内,相关系数均大于0.99,线性关系良好。除炔诺酮定量限为1.5μg/L,其他7种药物定量限均为1μg/L。在2、10、50μg/L添加水平下,药物的回收率为71.5%~92.3%,日内相对标准偏差(RSD)为2.2%~14.6%,日间RSD为3.2%~12.7%。本方法灵敏度高,适用于同化激素类药物残留的检测分析。     

超高效液相色谱-串联质谱法测定饲料中的喹烯酮

本研究采用超高效液相色谱-串联质谱法测定饲料中喹烯酮的残留量。样品经乙腈-乙酸乙酯（1:1,V/V提取、正己烷除脂净化后，用乙腈-0.2%甲酸作为流动相，经C18分离、LC-MS/MS多反应监测、正离子模式分析，基质匹配外标法定量。结果表明：在浓度为1.035～103.5 ng/mL，四种饲料喹烯酮基质匹配标准工作曲线线性关系良好，相关系数均在0.998以上；方法检出限为6.0μg/kg、定量限为20.0μg/kg，方法加标回收率为89.6%～116.0%、相对标准偏差为3.44%～7.19%，适用于配合饲料、浓缩饲料、精料补充料和添加剂预混合饲料中喹烯酮残留量的检测。     

盐酸克伦特罗确证测定样品前处理条件优化

为了简化样品前处理步骤,提高工作效率,节约成本,试验采用改进后的样品前处理方法对肉制品中的盐酸克伦特罗进行高效液相色谱串联质谱检测。样品经乙酸钠提取、高氯酸除蛋白质后,用10 mL乙酸乙酯萃取两次,然后用乙腈饱和的正己烷振荡离心除掉脂溶性杂质,最后用高效液相色谱串联质谱法进行检测。结果表明:在溶液pH值为11.0的条件下,用10 mL乙酸乙酯替代现行通用的10 mL饱和氯化钠溶液+10 mL异丙醇-乙酸乙酯(体积比为6∶4)萃取剂,并将净化过程中使用的阳离子交换小柱更改为用乙腈饱和的正己烷振荡离心,样品的回收率在90%以上。说明畜禽肌肉中盐酸克伦特罗的提取可以省略酶解步骤;同时以萃取法代替固相萃取小柱净化,节约检测成本,适用于不同类别肌肉中盐酸克伦特罗的检测。     

牛奶和牛血浆中头孢喹肟HPLC-MS/MS检测方法的建立

建立了头孢喹肟在牛奶和牛血浆中的高效液相色谱-串联质谱(HPLC-MS/MS)检测方法。牛奶样品用10%三氯乙酸沉淀蛋白,两次提取后过Strata-X-C固相萃取柱,30%乙腈洗脱后供HPLC-MS/MS检测。血浆样品用乙腈沉淀蛋白,高速离心后吸取0.2 mL上清液,与0.8 mL水混合后直接检测。以0.1%甲酸水-乙腈为流动相梯度洗脱,流速0.25 mL/min,进样量5!L。头孢喹肟在牛奶中的回收率在76.70%～87.02%之间,定量限为5 ng/mL。牛血浆中的回收率在89.41%～98.25%之间,定量限为2 ng/mL。结果表明,该方法简单快速、灵敏度高,适用于头孢喹肟在奶牛乳和血浆中的残留检测。     

喹烯酮在猪体内的代谢物研究

对5只猪按30 mg/kg单剂量口服给药,进行喹烯酮在猪体内侧链结构断开的代谢物研究。依据本试验建立的HPLC方法进行尿液代谢物含量测定。结果表明,喹烯酮以3-甲基-2-羧酸喹口恶啉的形式从尿中排出。     

The levels of zearalenone and its metabolites in plasma,urine and faeces of horses fed with naturally,Fusarium toxin–contaminated oats

Concentration profile of zearalenone (ZON) and its metabolites in plasma, urine and faeces samples of horses fed with Fusarium toxin–contaminated oats is described. In plasma, β‐zearalenol (β‐ZOL) was detected at high levels on day 10 of the study (3.21–6.24 μg/l). β‐Zearalenol and α‐zearalenol were the major metabolites in urine. Zearalenone, α‐ZOL and β‐ZOL were predominantly found in faeces. Zearalanone could also be detected in urine (1.34–5.79 μg/l) and faeces (1 μg/kg). The degree of glucuronidation was established in all sample types, approximately 100% in urine and plasma. Low per cent of glucuronidation (4–15%) was found in faeces samples. The results indicate the main conversion of ZON into β‐ZOL in horse. This finding could explain why horse is not susceptible to ZON in comparison with swine which produce α‐ZOL as a predominant metabolite.     

喹烯酮在鸡体内的代谢及药物动力学研究

以HPLC-MS/MS为定量手段,研究了喹烯酮经静脉注射(2.5 mg/kg)、口服(30 mg/kg)两种给药途径在鸡体内的代谢及药物动力学特征.鸡静脉注射喹烯酮后,血浆中检测到喹烯酮原药和1-脱氧喹烯酮;口服灌注喹烯酮后,血浆中检测到喹烯酮原药和3-甲基喹噁啉-2-羧酸(MQCA).喹烯酮在鸡体内的药动学数据采用统...     

Plasma pharmacokinetics of quinocetone in ducks after oral and intravenous administration

Quinocetone (QCT), an antimicrobial growth promoter, is widely used in food‐producing animals. However, information about pharmacokinetics (PK) of QCT in ducks still remains unavailable up to now. In this study, QCT and its major metabolites (1‐desoxyquinocetone, di‐desoxyquinocetone and 3‐methyl‐quinoxaline‐2‐carboxylic) in ducks were studied using a simple and sensitive UHPLC‐MS/MS assay. Twenty ducks were divided into two groups. (n = 10/group). One group received QCT by oral administration at dose of 40 mg/kg while another group received QCT intravenously at 10 mg/kg. Plasma samples were collected at various time points from 0 to 96 hr. QCT and its major metabolites in duck plasma samples were extracted by 1 ml acetonitrile and detected by UHPLC‐MS/MS, with the gradient mobile phase that consisted of 0.1% formic acid in water (A) and acetonitrile (B). A noncompartment analysis was used to calculate the PK parameters. The results showed that following oral dosing, the peak plasma concentration (C_max) of QCT was 32.14 ng/ml and the area under the curve (AUCINF_obs) was 233.63 (h ng)/ ml. Following intravenous dosing, the C_max, AUCINF_obs and Vss_obs were 96.70 ng/ml, 152.34 (h ng)/ ml and 807.00 L/kg, respectively. These data indicated that the QCT was less absorbed in vivo following oral administration, with low bioavailability (38.43%). QCT and its major metabolites such as 1‐desoxyquinocetone and 3‐methyl‐quinoxaline‐2‐carboxylic were detected at individual time points in individual ducks, while the di‐desoxyquinocetone was not detected in all time points in all ducks. This study enriches basic scientific data about pharmacokinetics of QCT in ducks after oral and intravenous administration and will be beneficial for clinical application in ducks.     

A high-performance liquid chromatography method for determination of 4-aminopyridine in tissues and urine

An analytical method was developed to measure 4-aminopyridine in tissues and urine to determine appropriate diagnostic samples in acute poisoning cases. Tissues from rats dosed with 4-aminopyridine were extracted with methylene chloride. Extracts were analyzed by high-performance liquid chromatography using an isocratic solvent system of acetonitrile and aqueous solution (15/85 v/v) consisting of 0.015 M sodium salt of l-heptane-sulfonic acid, 0.002 M tetramethylammonium bromide, and 0.01 M sodium dihydrogen phosphate adjusted to pH 3.0 with phosphoric acid. We concluded that suitable diagnostic samples for acute poisoning cases include stomach contents, kidney, liver, and urine.     

牛奶中苯并咪唑类药物及其代谢物残留的UPLC-MS/MS检测方法研究

建立了牛奶中苯并咪唑类药物及代谢物残留的UPLC-MS/MS检测方法。牛奶样品在弱碱性条件下经乙腈沉淀蛋白后,用乙酸乙酯提取,再经正己烷脱脂,MCX固相萃取柱净化,采用UPLC-MS/MS多反应监测(MRM)模式检测,外标法定量。本方法对苯并咪唑类药物及代谢物的检测限均为5μg/g,定量限均为10μg/g,在10～200μg/L添加浓度范围内回收率为69.9%～113.1%之间,批内变异系数在1.36%～11.48%之间,批间变异系数在1.09%～9.87%之间。本方法分析速度快,灵敏度高,重现性好,各项技术指标均满足国内外相关法规要求,可用于牛奶中苯并咪唑类药物及代谢物残留的检测。     

UPLC-MS/MS法测定动物源性食品中氯苯胍及其代谢物残留

为快速有效地检测动物源性食品中氯苯胍及其代谢物残留,研究建立一种在鸡蛋、鸡肉、牛肉、鱼肉和猪肉5种动物源性食品中,同时检测氯苯胍及其代谢物（对氯苯甲酸、对氯苯甲酰氨基乙酸）残留的超高效液相色谱-串联质谱（UPLC-MS/MS）法。样品经过2%（V/V）甲酸乙腈溶液提取,无水硫酸钠去除水分,氮吹浓缩后甲醇复溶,正己烷除脂,高速冷冻离心,得到净化后的样品进行上机测定。选用Waters ACQUITY UPLC BEH C18色谱柱（2.1 mm×100 mm,1.7 μm）,将甲醇-0.1%甲酸水溶液作为流动相进行梯度洗脱。通过多反应检测（MRM）,在正/负离子模式下,采用基质匹配外标法,同时对3种化合物进行定性和定量分析。结果显示,氯苯胍、对氯苯甲酸和对氯苯甲酰氨基乙酸在各自浓度范围内线性关系良好,相关系数R²>0.999。氯苯胍的检出限（LOD）和定量限（LOQ）分别为0.5和1.0 μg/kg,对氯苯甲酸的LOD和LOQ分别为2.5和5.0 μg/kg,对氯苯甲酰氨基乙酸的LOD和LOQ分别为1.0和2.5 μg/kg。不同基质中,3种化合物在4个添加水平（氯苯胍：1.0、25、50、100 μg/kg;对氯苯甲酸：5.0、25、50、100 μg/kg;对氯苯甲酰氨基乙酸：2.5、25、50、100 μg/kg）的平均回收率为76.0%~95.9%,相对标准偏差（RSDs,n=6）为2.6%~10.6%。基质效应|ME|为0.2%~26.2%,其中氯苯胍在鸡蛋中,对氯苯甲酰氨基乙酸在鸡肉、牛肉和鱼肉中存在较强的基质效应（|ME|>20%）,空白猪肉可作为代表基质用于3种化合物的定量分析。本方法前处理简单,灵敏度较高,重现性好,可用于动物源食品中氯苯胍及其代谢物残留的测定。     

Disposition of cyadox in domesticated cats following oral,intramuscular, and intravenous administration

Cyadox (CYX) is a synthetic antibacterial agent of quinoxaline with much lower toxic effects. A safety criterion of CYX for clinical use was established by studying the pharmacokinetics and metabolism of CYX after oral (PO), intramuscular (IM), and intravenous (IV) administration. CYX was administered in six domesticated cats (three males and three females) by PO (40 mg/kg.b.w.), IM (10 mg/kg.b.w.), and IV (10 mg/kg.b.w.) routes in a crossover pattern. Highly sensitive liquid chromatography with ultraviolet detection (HPLC-UV) method was developed for detection of CYX and its metabolites present in plasma, urine, and feces. The bioavailability of CYX after PO and IM routes was 4.37% and 84.4%. The area under curves (AUC), mean resident time (MRT), and clearance (CL) of CYX and its metabolites revealed that CYX quickly metabolized into its metabolites. The total recovery of CYX and its main metabolites was >60% after each route. PO delivery suggesting first pass effect in cats that might make this route suitable for intestinal infection and IM injection could be better choice for systemic infections. Less ability of glucuronidation did not show any impact on CYX metabolism. The findings of present study provide detailed information for evaluation of CYX.     

Pharmacokinetic and urine profile of tramadol and its major metabolites following oral immediate release capsules administration in dogs

The aim of the present paper was to test the oral administration of oral immediate release capsules of tramadol in dogs, to asses both its pharmacokinetic properties and its urine profile. After capsules administration of tramadol (4 mg/kg), involving eight male Beagle dogs, the concentration of tramadol and its main metabolites, M1, M2 and M5, were determined in plasma and urine using an HPLC method. The plasma concentrations of tramadol and metabolites were fitted on the basis of mono- and non-compartmental models, respectively. Tramadol was detected in plasma from 5 min up to 10 h in lesser amounts than M5 and M2, detected at similar concentrations, while M1 was detected in negligible amounts. In the urine, M5 and M1 showed the highest and smallest amount, respectively; M1 and M5 resulted widely conjugate with glucuronic acid. In conclusion, after oral administration of tramadol immediate release capsules, the absorption of the active ingredient was rapid, but its rapid metabolism quickly transformed the parental drug to high levels of M5 and M2, showing an extensive elimination via the kidney. Hence, in the dog, the oral immediate release pharmaceutical formulation of tramadol would have different pharmacokinetic behaviour than in humans.