乙酰氨基阿维菌素乳剂HPLC含量检测方法的建立

[目的]建立高效液相色谱法测定乙酰氨基阿维菌素乳剂含量的方法。[方法]采用C18（150×4．6mm,5μm）色谱柱,以乙腈-水（70：30）为流动相,流速为1．0mL/min,检测波长为245nm,进样量为20μL,柱温为25℃。[结果]乙酰氨基阿维菌素在0．1～20μg/mL浓度范围内呈现良好的线性关系,标准曲线方程为C=1．6015A-0．00206,r=1．000（n=5）,该方法的RSD在0．72％～1．40％,平均回收率在96．5％～100．5％。[结论]该方法灵敏度高、准确度高、重现性好、简便快速,可用于乙酰氨基阿维菌素乳剂和其他剂型的质量控制。     

牛血浆中乙酰氨基阿维菌素HPLC-FLD检测方法的建立

为了研究乙酰氨基阿维菌素(eprinomectin, EPR)缓释注射液在牛体内的药代动力学情况,试验建立了检测牛血浆中EPR浓度的高效液相色谱荧光(HPLC-FLD)法,并进行了系统的方法学验证,向空白牛血浆样品中加入内标阿维菌素(AVM),用乙腈沉淀蛋白质,再用固相萃取柱进行净化,洗脱液浓缩至干后以N-甲基咪唑和三氟乙酸酐对EPR及AVM进行衍生化,采用HPLC-FLD法进行检测。该检测方法所用色谱柱为Elite Hypersil ODS(4.6 mm×250 mm, 5μm);流动相为甲醇∶乙腈∶水=64∶32∶4;流速为1 mL/min;柱温为35℃;荧光检测器激发波长为365 nm,发射波长为463 nm。结果表明：建立的HPLC-FLD检测方法中EPR的保留时间为8.076 min, AVM保留时间为12.922 min。检测限为0.5 ng/mL,定量限为1 ng/mL。血浆样品中EPR浓度在1～100 ng/mL之间时,血浆药物浓度与峰面积之比呈良好的线性关系,线性方程为y=0.912x+0.924,相关系数(R² )为0.994 7。准确度为80...     

乙酰氨基阿维菌素缓释注射剂中乙酰氨基阿维菌素含量与有关物质HPLC检测方法的建立

试验旨在建立一种高效液相色谱检测方法,同时测定乙酰氨基阿维菌素(EPR)缓释注射剂的主成分与有关物质,采用外标法计算主成分的含量,采用自身对照法计算有关物质的含量。色谱柱为Phenomenex Luna 5 μ-C8-100A 250 mm×4.60 mm,5 μm;色谱条件为:流动相为乙腈-0.1%高氯酸水溶液,梯度洗脱,流速为1.5 mL/min,检测波长为245 nm,柱温为35 ℃,进样量为20 μL。结果表明,EPR缓释注射剂主成分与杂质分离度良好,B1a与B1b之间分离度>3;在EPR浓度为1.5625~1 000 μg/mL的范围内线性关系良好;EPR的检测限与定量限分别为0.01和0.34 μg/mL,3种精密度的相对标准偏差(RSD)均<2%,稳定性的RSD为0.28%,加样回收率为102.54%,且RSD为3.14%(n=9)。耐用性试验表明,EPR缓释注射剂主成分的分离度均>1.5,理论塔板数>4 500,表明该检测条件的耐用性良好。3批样品中,EPR缓释注射剂含量的平均值为102.60%,B1b占B1a与B1b之和的1.68%,总杂质的平均含量为2.57%。建立的EPR缓释注射剂中主成分含量与有关物质的测定方法具有简便、专属性强、灵敏度高、结果准确等特点,可用于EPR缓释注射剂的质量控制。     

两种固相萃取柱在乙酰氨基阿维菌素药动学前处理中的比较

为评价乙酰氨基阿维菌素(EPR)药动学前处理中两种固相萃取(SPE)柱的净化、萃取效果,首先在空白胎牛血清中加入一定量的EPR标准溶液,经色谱甲醇提取后,分别经Agilent和Waters公司的C_(18) SPE柱对其进行萃取,再经N-甲基咪唑和三氟乙酸酐衍生化,最后用超高效液相色谱-荧光检测器进行测定;同时,将等量的EPR标准溶液进行衍生化,用超高效液相色谱-荧光检测器进行测定,将其结果作为对照;以绝对回收率作为评价两种SPE柱净化、萃取EPR效果的标准。结果显示,含有EPR的胎牛血清分别经Agilent和Waters公司的C_(18) SPE柱萃取后,两者的EPR峰形均尖锐对称且无明显杂质峰,但绝对回收率有差异,分别为94.50%和85.79%。结果表明,Agilent公司的C_(18) SPE柱对EPR的萃取效果更理想。     

3种固相萃取柱在测定牛血清样品中乙酰氨基阿维菌素前处理中的比较研究

初步评价在乙酰氨基阿维菌素药动学前处理中3种固相萃取柱对乙酰氨基阿维菌素的净化、萃取效果。首先在空白胎牛血清中加入一定量的乙酰氨基阿维菌素标准溶液,经色谱甲醇提取后,分别经Agilent公司、Waters公司和Agela Technologies公司的C₁₈SPE柱进行萃取(分别简称A固相萃取柱、W固相萃取柱、AT固相萃取柱),再经N-甲基咪唑和三氟乙酸酐衍生化,最后用超高效液相色谱-荧光检测器进行测定。与此同时,将等量的乙酰氨基阿维菌素标准溶液进行衍生化,用超高效液相色谱-荧光检测器进行测定,其结果作为对照。以绝对回收率作为评价3种SPE柱净化、萃取EPR效果的标准。结果显示,含有EPR的胎牛血清经A固相萃取柱萃取后,EPR峰形尖锐对称且无明显杂质峰,其绝对回收率为80.79%;经W固相萃取柱萃取后,乙酰氨基阿维菌素峰形尖锐对称且无明显杂质峰,其绝对回收率为83.61%;经AT固相萃取柱萃取后,乙酰氨基阿维菌素峰形尖锐对称且无明显杂质峰,其绝对回收率仅为64.20%。相对于A与AT固相萃取柱,Waters公司的C₁₈SPE柱萃取EPR的效果更好。研究结果为后期乙酰氨基阿维菌素的药物代谢动力学试验奠定了基础。     

乙酰氨基阿维菌素国家对照品的研制

以乙酰氨基阿维菌素为原料研制首批乙酰氨基阿维菌素国家对照品,并进行质量评价。采用高效液相色谱法和质谱法对原料进行结构确证,分装后的乙酰氨基阿维菌素对照品采用质量平衡法定值,同时采用高效液相色谱外标法加以佐证。结果显示,以质量平衡法计算乙酰氨基阿维菌素(B_1a+B_1b)含量为97.79%,液相色谱外标法测定含量为98.18%,两种方法测定结果基本一致。本次研制的乙酰氨基阿维菌素对照品可用于乙酰氨基阿维菌素及其制剂的鉴别与含量测定。     

酒石酸乙酰异戊酰泰乐菌素在猪体内的药代动力学研究

健康猪口服酒石酸乙酰异戊酰泰乐菌素(AIV),不同时间点采血,高效液相色谱法测定血药浓度,残数法拟合药时曲线,计算药动学参数.结果表明,6头猪口服AIV(20mg/kg体重)后,其药动学表现有吸收因素二室模型特征.最佳药时曲线方程为:C=0.654·e-2.0593·t+0.981 3·e-3.0973·t-1.635 3·e-63.3197·t;吸收半衰期(t1/2Ka)为0.014 9±0.012 7 d,消除半衰期(t1/2ke)为0.1138±0.055 5 d,药时曲线下面积(AUC)为0.604 5±0.068 3(μg/mL)·d.表明酒石酸乙酰异戊酰泰乐菌素在猪体内吸收迅速,消除相对较慢.     

氟苯尼考静注及肌注在鸡体内药代动力学研究

健康AA肉鸡 36只 ,随机分成 4组 ,以 15mg/kg和 30mg/kg两种剂量静注、肌注分别给予氟苯尼考。用高压液相色谱法测定血浆中的药物浓度 ,采用 3p97药代动力学程序软件处理药 时数据。静注药 时数据符合二室开放模型 ,主要药代动力学参数 :15mg/kg剂量组Vd(ss) 1 5 7± 0 16L/kg ,T1/2α43 96± 12 2 7min、T1/2 β16 8 18±45 2 4min、CL(s) 0 0 17± 0 0 0 30L/ (kg·min)、AUC886 40± 146 5 3(μg/ml)·min ;30mg/kg剂量组Vd(ss) 1 42±0 2 3L/kg ,T1/2α41 48± 8 6 4min、T1/2 β180 80± 74 97min、CL (s) 0 0 17± 0 0 0 2 9L/ (kg·min)、AUC176 7 15±2 6 8 2 3(μg/ml)·min。肌注药 时数据符合一室开放模型 ,主要药代动力学参数 :15mg/kg剂量组T1/2 (ka) 10 2 5±9 19min、T1/2 (ke) 15 2 41± 73 0 9min、C(max) 3 5 0± 1 13μg/ml、AUC837 88± 16 0 85 (μg/ml)·min、F94 5 3% ;30mg/kg剂量组T1/2 (ka) 11 97± 7 5 9min、T1/2 (ke) 15 2 41± 73 0 9min、C(max) 6 79± 1 38μg/ml、AUC172 5 2 9±35 7 98(μg/ml)·min、F97 6 3%。实验结果表明 :氟苯尼考在鸡体内吸收好 ,分布快 ,消除也快。静注、肌注后曲线下面积AUC与剂量呈比例关系 ,各参数无剂量依赖性。     

鸡血浆中黄芩苷及绿原酸的HPLC法建立

建立了测定鸡血浆中复方慢呼抗口服液主要成分黄芩苷和绿原酸的高效液相色谱法.流动相为乙腈、1％冰醋酸,梯度洗脱30 min,黄芩苷和绿原酸的波长分别为280、327 nm,流速1 mL/min.分别采用高氯酸法、甲醇乙腈法、正丁醇法处理血浆,选取最优方法进行考察.甲醇乙腈法处理血浆,方法专属性好,回收率较高,线性关系良好,精密度及准确度较高,可用于药代动力学研究.     

液相色谱法测定牛奶中三聚氰胺残留量的不确定度

通过数学建模,对GB/T22388-2008中HPLC法测定牛奶中三聚氰胺残留量的不确定度进行分析。将各个分量分化,运用最小二乘法对标准曲线拟合的不确定度,用极差法对测定次数较少时引起的不确定度,添加回收率的不确定度等进行分析。结果表明,合成标准不确定度U（X）=0.040,当取样量为2.00g,k=2（95%置信度）时,测得牛奶中三聚氰胺的含量为（2.00±0.160）mg/kg。     

鸡猪排泄物中恩诺沙星和环丙沙星含量HPLC检测方法的建立

建立了测定鸡、猪排泄物中恩诺沙星及环丙沙星含量的高效液相-荧光检测方法.将猪粪和鸡粪尿混合物样品分别用甲醇氨水溶液和醋酸甲醇溶液浸提,猪尿用固相萃取小柱富集净化,流动相为乙腈-三乙胺磷酸溶液（0.02 mol/L）,荧光激发波长280 nm,发射波长450 nm.检测结果表明,排泄物样品中恩诺沙星和环丙沙星含量的检测定量限,鸡粪尿混合物为0.010 μg/g,猪尿0.005 μg/mL,猪粪为0.020 μg/g.外标法标准曲线的线性范围鸡粪尿混合物中恩诺沙星为0.010～100.000 μg/g、环丙沙星为0.010～50.000 μg/g,猪尿和猪粪中恩诺沙星和环丙沙星的线性范围分别为0.005～0.500 μg/mL和0.020～1.000 μg/g.恩诺沙星和环丙沙星的回收率分别大于75%和88%.HPLC方法的样品前处理和检测方法简便、快捷,准确性较微生物检测法高.     

Clindamycin bioavailability and pharmacokinetics following oral administration of clindamycin hydrochloride capsules in dogs

Oral bioavailability and pharmacokinetic behaviour of clindamycin in dogs was investigated following intravenous (IV) and oral (capsules) administration of clindamycin hydrochloride, at the dose of 11 mg/kg BW. The absorption after oral administration was fast, with a mean absorption time (MAT) of 0.87+/-0.40 h, and bioavailability was 72.55+/-9.86%. Total clearance (CL) of clindamycin was low, after both IV and oral administration (0.503+/-0.095 vs. 0.458+/-0.087 L/h/kg). Volume of distribution at steady-state (IV) was 2.48+/-0.48 L/kg, indicating a wide distribution of clindamycin in body fluids and tissues. Elimination half-lives were similar for both routes of administration (4.37+/-1.20 h for IV, vs. 4.37+/-0.73 h for oral). Serum clindamycin concentrations following administration of capsules remained above the MICs of very susceptible microorganisms (0.04-0.5 microg/mL) for 12 or 10 h, respectively. Time above the mean inhibitory concentration (MIC) is considered as the index predicting the efficacy of clindamycin (T(>MIC) must be at least 40-50% of the dosing interval), so a once-daily oral administration of 11 mg/kg BW of clindamycin can be considered therapeutically effective. For less susceptible bacteria (with MICs of 0.5-2 microg/mL) the same dose should be given but twice daily.     

Linearity of eprinomectin pharmacokinetics in lactating dairy sheep following pour-on administration: excretion in milk and exposure of suckling lambs

Pharmacokinetics of eprinomectin (EPR) were studied in blood plasma and milk in two groups of six Istrian Pramenka dairy sheep and their suckling lambs following pour-on administration of EPR to ewes at dose levels of 0.5 and 1 mg/kg. Maximum concentration in plasma was 2.22 and 5.25 μg/l, and AUC was 13.6 and 33.7 μg day/l for the 0.5 and 1.0 mg/kg dose, respectively. These results indicate that drug exposure with a dose of 0.5 mg/kg, which is commonly used in cattle, may be subtherapeutic. The concentration time course in milk paralleled plasma concentrations. In the dose range studied, linear pharmacokinetics of EPR were demonstrated. Milk-to-plasma AUC ratio was 0.79 ± 0.12 and 1.12 ± 0.43; the fraction of dose recovered in milk was 0.037 ± 0.011 and 0.058 ± 0.027% for the low and high dose, respectively. Maximum residual levels in milk were below the maximum acceptable level of 20 μg/kg; however, EPR was detected in all samples investigated. Despite low permeability in milk, AUC in plasma of suckling lambs was between 20 and 30% of the AUC in plasma of ewes.     

高效液相色谱法测定草地早熟禾4种内源激素的方法

建立了高效液相色谱法测定草地早熟禾中玉米素（ZT）、吲哚乙酸（IAA）、脱落酸（ABA）和赤霉素（GA₃）的方法。样品用80%甲醇水溶液冷浸提取。色谱柱为Extend-C₈（4.6×150 mm,5 μm）色谱柱,流速为1 mL·min^-1,进样量均为20 μL。前3种激素的流动相为甲醇和0.6%冰乙酸梯度洗脱;检测波长为254 nm。GA₃流动相为乙腈：0.6%冰乙酸=60：40等度洗脱;检测波长为208 nm。4种激素在一定检测范围内具有良好的线性关系,相关系数均达0.99以上;平均回收率为83.78%～99.09%;相对标准偏差均小于5%。结果表明：该方法灵敏度、精密度和准确度好,可以满足草地早熟禾ZT,IAA,ABA和GA₃ 4种激素的检测。     

The effect of fasting on the plasma disposition of triclabendazole following oral administration in goats

This study was designed to investigate the effect of feeding on the plasma disposition of triclabendazole (TCBZ) in goats following oral administration. A total of eight goats, aged 14–16 months and weighing 20–30 kg were used in this study. The animals were allocated into two groups (fasted and fed groups) of four animals each. The goats in fed group were fed ad libitum but the animals in fasted group were not fed 24 h before and 6 h after drug administration. Commercial oral drench formulation of TCBZ (Endex-K, 5%) was administered orally to animals in two groups at dose of 10 mg/kg bodyweight. Heparinized blood samples were collected between 1 and 192 h after treatment and the plasma samples were analysed by high performance liquid chromatography (HPLC) for TCBZ, TCBZ sulphoxide (TCBZ–SO), and TCBZ sulphone (TCBZ–SO₂). Relatively very low concentration of TCBZ parent drug was detected between 2 and 48 h, but TCBZ–SO and TCBZ–SO₂ metabolites were present between 2 and 192 h in the plasma samples of fed and fasted animals. Fasting significantly enhanced the plasma concentration of TCBZ and its metabolites. The availability of TCBZ, TCBZ–SO and TCBZ–SO₂ in the plasma samples of fasted goats were markedly greater compared to those of fed goats. It was concluded that fasting decreases the digesta flow rate and prolongs the retention of the drug into the gastrointestinal tract, resulting in enhanced quantitative gastrointestinal absorption or systemic availability of TCBZ and its metabolites in fasted goats.     

林可霉素微球制剂在鹅体内的药代动力学研究

为了解林可霉素微球制剂在动物机体内的药代情况,在鹅体内进行了两种剂型药物的药代动力学比较研究.试验选取健康鹅分为两组,即对照组肌肉注射30％林可霉素水溶液,试验组肌肉注射30％林可霉素微球溶液,0.5 mL/只.选取0～72 h内的不同时间点采集鹅血浆样品,应用高效液相色谱法(HPLC)对鹅血浆中林可霉素的含量进行检测...     

HPLC方法同步测定四黄止痢复方中黄芩苷和小檗碱的含量

本实验旨在建立HPLC同步测定四黄止痢复方中黄芩苷和小檗碱的方法,四黄止痢复方中草药经甲醇提取,以甲醇-0.1%磷酸水为流动相进行梯度洗脱,C18色谱柱分离,278 nm波长检测。结果表明:在0.01～0.12 mg/L浓度呈良好的线性关系,加样回收率分别为(98.058±0.897)%、(98.401±0.882)%;重复性良好,相对标准偏差<1%。因此本法适用于四黄止痢复方中黄芩苷和小檗碱含量测定。     

Analytical determination and pharmacokinetics of major metabolites of carbasalate calcium in broilers following oral administration

As a newer anti-inflammatory agent, carbasalate calcium is used in various animal species. In this study, the pharmacokinetics of carbasalate calcium was investigated in broilers. Broilers, with body weight of 2.0 ± 0.3 kg, were administrated carbasalate calcium soluble powder at a single dose of 40 mg/kg body weight orally. The plasma concentrations of its metabolites, aspirin (ASA), salicylic acid (SA) and gentisic acid (GA) were determined by LC-MS/MS method and the pharmacokinetic parameters were calculated by noncompartmental analysis. After oral administration of carbasalate calcium, the plasma drug concentration for ASA, SA and GA reached a peak (C(max) ) of 8.88 ± 1.31, 42.6 ± 4.62 and 10.1 ± 2.16 μg/mL at 0.170, 2.00 and 2.00 h, respectively. The terminal half-life (t(1/2λz) ) of ASA, SA and GA was 11.2 ± 8.04, 23.7 ± 17.1 and 28.6 ± 4.90 h, respectively. In conclusion, analytical method for the quantification of ASA, SA and GA in plasma in the broilers was developed and validated. In broilers, carbasalate calcium is quickly metabolized in ASA and ASA is rapidly converted to SA and one of the metabolites of SA is GA.