建立一种基于超高效液相色谱-串联质谱测定猪肉中地克珠利和妥曲珠利残留的方法

本文建立了一种检测猪肉中地克珠利和妥曲珠利残留的超高效液相色谱-串联质谱方法。地克珠利和妥曲珠利在10.0μg/kg～500.0μg/kg线性范围内,标准曲线的相关系数(r)均大于0.996,呈现良好的线性关系。地克珠利和妥曲珠利的检出限分别为1.22μg/kg和1.25μg/kg,在加标回收试验中的回收率范围分别为81.4%～105.0%和86.0%～103.0%,相对标准偏差范围为3.8%～6.2%。试验结果表明,该方法简单、快速、准确,且检出限低、回收率高,能适用于猪肉中地克珠利和妥曲珠利残留的检测。     

妥曲珠利在肉鸡组织中残留的研究

用高效液相色谱法(HPLC)检测肉鸡肌肉、肝脏和肾脏组织中妥曲珠利的残留量。将妥曲珠利以20、200和2 000μg/kg的含量分别添加到空白组织中,测得肌肉、肝脏和肾脏组织的回收率大于75%,变异系数均低于7%。用该方法测定肌肉、肝脏和肾脏组织中妥曲珠利的最低检测限为10μg/kg。肉鸡分别在第9,10,16,17,23,24天以8 mg/kg的剂量灌服2.5%妥曲珠利溶液,每天给药1次。最后一次给药后测定不同组织中妥曲珠利的浓度。停药后肌肉、肝脏、肾脏组织中妥曲珠利的残留量逐渐下降;停药第6天后肌肉中检测不到妥曲珠利,停药后第7天肝脏和肾脏组织中均检测不到。     

鸡组织中地克珠利和妥曲珠利残留HPLC检测方法的建立

建立了同时检测鸡组织中地克珠利和妥曲珠利残留的高效液相色谱.经乙腈提取,正己烷脱脂,旋转蒸发浓缩后,以0.05mol/L磷酸/三乙胺(pH3.0):乙腈(40:60)作为流动相,反相高效液相色谱-紫外检测法检测,检测波长240 nm.鸡组织中地克珠利和妥曲珠利的回收率分别为92.0%～102.0%和83.4%～89.0%,变异系数为5.9%～12.2%,地克殊利和妥曲珠利的检测限分别为0.012 mg/kg和0.010 mg/kg,在0.05～1.0 mg/L质量浓度范围内呈良好的线性相关.该法样品处理简单,可同时检测地克珠利和妥曲珠利的残留,且准确度和精密度均符合残留分析的要求.     

HPLC对妥曲珠利纳米乳中有效成分含量的检测

建立高效液相色谱法测定妥曲珠利纳米乳中妥曲珠利含量的方法。色谱柱为Agilent C18(4.6mm×150mm,5μm);流动相为磷酸二氢钾缓冲液(pH3):乙腈(45:55),流速1mL/min,紫外检测波长240nm,柱温30℃,进样量20μL。结果表明,妥曲珠利含量在0.0625μg/mL～100μg/mL范围内与峰面积呈良好的线性关系,检测限为5ng/mL,定量限为15ng/mL,平均加样回收率为99.73%。试验表明,该方法简便灵敏,结果准确可靠,可用于妥曲珠利纳米乳中妥曲珠利的质量控制。     

妥曲珠利纳米乳在鸡体内药代动力学研究

为了解妥曲珠利纳米乳在鸡体内的药物动力学过程,按7mg/kg经口灌服妥曲珠利纳米乳,高效液相色谱法测定血药浓度,通过3P87药物动力学程序软件分析药时数据,同时以妥曲珠利溶液为对照。结果表明,健康肉鸡单次灌服妥曲珠利纳米乳和妥曲珠利溶液后血药浓度-时间数据均符合有吸收二室模型,主要药代动力学参数分别为:T1/2α:11.202h±0.707h和4.203h±0.303h,T1/2β:46.689h±9.247h和23.774h±1.744h,AUC:368.958(μg·mL-1)h±37.36)/(μg·mL-1)h和175.249(μg·mL-1)h±14.256)/(μg·mL-1)h。提示妥曲珠利纳米乳在鸡体内具有明显的缓释性,同时生物利用度极显著提高。     

曲妥珠单抗的高效液相色谱定量分析

本文采用高效液相色谱法以磷酸盐缓冲液为流动相,凝胶柱和紫外检测器定量分析曲妥珠单抗注射液中曲妥珠单抗的药物含量。结果表明曲妥珠单抗注射液浓度在10μg/m L~1mg/m L范围内浓度与紫外吸收峰面积呈良好的线性关系,线性相关系数r≥0.99。     

妥曲珠利在鸡组织内的残留研究

研究鸡单剂量喂服(50 mg/kg·d,100mg/kg·d,连服2 d)妥曲珠利后在肝脏、肾脏、肌肉组织中的残留量,以便制定妥曲珠利预混剂的休药期.用乙腈-乙酸乙酯(3/2,v/v)提取组织中的药物,利用高效液相色谱法测定组织中妥曲珠利的浓度.试验结果表明,100mg/kg饲料添加妥曲珠利在鸡体内休药期为14 d,50 mg/kg时休药期为8 d.该结果与农业部制定的无公害食品饲养兽药使用准则中所规定的75～100 mg/kg鸡饮水妥曲珠利的休药期一致.     

HPLC法测定猪血浆中帕托珠利的方法学建立

建立了HPLC法测定猪血浆中帕托珠利含量的方法。色谱柱为安捷伦ZORBAX Eclipse XDB-C18柱(250 mm×4.6 mm,5μm),流动相0.2%乙酸水溶液-乙腈(47∶53),柱温35℃,流速为1 m L/min,检测波长为250 nm。在本方法条件下,帕托珠利在0.1～10μg/m L浓度范围内线性关系良好(r0.999),检测限(LOD)为0.04μg/m L,定量限(LOQ)为0.1μg/m L,批内和批间回收率均大于90%,批内和批间精密度RSD均小于9%。本方法简单、准确、快速,可用于测定猪血浆中帕托珠利的含量。     

两种妥曲珠利混悬液口服给药在仔猪的药动学比较研究

16只体重较一致的健康断奶仔猪随机分成2组,采用单剂量平行随机对照试验设计,分别单剂量(20 mg/kg体重,以妥曲珠利计)经口内服国产(受试品)和进口(对照品)妥曲珠利混悬液。结果表明,与妥曲珠利混悬液对照品相比较,妥曲珠利触变混悬液受试品单剂量内服给药吸收和消除较慢,但药物吸收完全。给药后按预定时间采集血样,血浆中妥曲珠利含量采用HPLC紫外检测器进行分析。实测血药浓度-时间数据采用Winnonlin5.2药动学分析软件计算药代动力学参数。结果显示,妥曲珠利混悬液对照品单剂量内服后,其平均消除半衰期(T1/2β)约为40.806 h,达峰时间(Tmax)和峰值浓度(Cmax)分别为16.500 h和27.494 mg/L,平均药时曲线下面积(AUC)为1 375.738(μg/m L/h),平均滞留时间(MRT)为50.677 h;妥曲珠利触变混悬液受试品单剂量内服后,其T1/2β约为51.642 h,Tmax和Cmax分别为37.500 h和21.452mg/L,AUC为1 843.842μg/m L/h,MRT为64.058 h,相对生物利用度为134.02%。与妥曲珠利混悬液对照品相比,妥曲珠利触变混悬液受试品口服吸收AUC(P=0.020)、Tmax(P=0.001)、MRT(P=0.019)有显著性差异;但两种混悬剂的其他药动学参数,如T1/2β(P=0.224)、Cmax(P=0.146)无显著差异。     

高效液相色谱法测定鸡血浆中帕托珠利和托曲珠利含量研究

为建立一种测定鸡血浆中帕托珠利和托曲珠利含量的高效液相色谱法，试验采用C₁₈色谱柱，分别以0.2%乙酸水-乙腈(47∶53)和0.02 mol/L磷酸二氢钾缓冲液(pH 3.0)-乙腈(40∶60)为流动相，柱温分别为35℃和30℃，流速为1 mL/min，紫外检测器检测，检测波长分别为250 nm、240 nm，外标法定量建立检测方法。结果显示，帕托珠利和托曲珠利的浓度与色谱峰面积在0.10～20.00μg/mL浓度范围内线性关系良好(R²>0.999)，帕托珠利平均加样回收率为89.65%～96.12%，托曲珠利平均加样回收率90.84%～94.27%，批内和批间变异系数均小于5%。结果表明，建立的高效液相色谱法简便、有效、重现性良好，可用于鸡血浆中帕托珠利和托曲珠利含量的测定。     

妥曲珠利固体分散物的制备

为增加难溶性药物妥曲珠利的溶出度,加速药物在体内的溶解,吸收,提高妥曲珠利的生物利用度。以聚乙二醇6000为载体,加入助溶剂Z,采用了熔融法来制备妥曲珠利固体分散体,用正交设计方法优选制剂工艺,确定出最优处方为：妥曲珠利：PEG-6000：助溶剂Z=1：6：1．6（g／g）。妥曲珠利原料药在水中溶解度为4．12×10^-4g／L;妥曲珠利－PEG-6000（1：6）的溶解度为0．78g／L,体外溶出度达到88．75％。初步稳定性实验结果表明妥曲珠利固体分散物比较稳定,在水溶液中可以稳定存在,将妥曲珠利制备成固体分散剂可以很好的提高其溶出度。     

Sulfonamide and toltrazuril therapy of experimental turkey coccidiosis

Following experimental infection of caged turkeys with a mixed oocyst suspension of E. meleagrimitis, E. adenoeides and E. gallopavonis, the efficacy of sulfachlorpyrazine, sulfaquinoxaline + pyrimethamine, sulfaquinoxaline + diaveridine, and toltrazuril was investigated based on clinical and parasitological parameters. Infected turkeys developed severe clinical symptoms. Only weak symptoms were observed in those groups which were treated with the sulfa- and sulfa-DHFR-inhibitors. The toltrazuril-treated group remained free of clinical symptoms. At the 8th day after infection, the clinical lesions coincided with the intensity of the gut lesions together with parasitological findings based on microscopical examination of mucosal smears. The same coincidence was observed for parameters such as oocyst excretion and body weight development.     

妥曲珠利微晶体的制备及其在家兔体内的药动学

采用反溶剂法制备妥曲珠利微晶体,利用显微镜观察妥曲珠利微晶体与妥曲珠利原药显微特征差异,并在25℃条件下测定两者体外溶出速率差异。将12只家兔随机分为2组,每组6只,分别按药物剂量10mg/kg灌胃,单剂量给药,采用HPLC检测血药浓度;用DAS2.0药代动力学程序计算药代动力学参数。结果显示,成功制备了妥曲珠利微晶体,微晶体与原药的显微特征差异明显,体外溶出速率明显加快;家兔单剂量灌胃妥曲珠利和微晶体后,主要药动学参数Cmax分别为（8.925±0.360）mg/L和（12.510±0.525）mg/L,tmax均为24h,AUC（0-∞）分别为（411.605±20.918）mg/（L·h）和（578.650±11.664）mg/（L·h）,相对生物利用度为140.6%,药时数据符合一级吸收二室模型。结果表明,HPLC法适用于妥曲珠利血浆浓度的测定;妥曲珠利微晶体与妥曲珠利原药相比,体内吸收速率和吸收程度有较大的提高。     

Efficacy of toltrazuril against intestinal and hepatic coccidiosis in rabbits

The anticoccidial effect of toltrazuril (Bay Vi 9142) against Eimeria flavescens, E. intestinalis, E. magna, E. perforans and E. stiedai was tested in experimentally-infected rabbits. Continuous administration of 10-15 p.p.m. of the drug in the drinking water was highly effective in reducing oocyst output of all five species and in preventing clinical signs and macroscopic lesions. Sporulation of excreted oocysts was not affected. After 5 weeks of medication, no negative influence was noted on zootechnic performance of growing healthy rabbits. Medication of rabbits with 25 p.p.m. only during schizogony or gamogony (2 days of treatment, repeated after 5 days) quickly reduced clinical signs and oocyst output. When administered during late schizogony or gamogony, toltrazuril allowed development of immunity against reinfection with homologous species.     

Chemoprophylaxis of coccidiosis in lambs with a single oral dose of toltrazuril

The prophylactic efficacy of a single oral dose of toltrazuril against coccidiosis (mixed Eimeria infections) in naturally infected lambs was evaluated in two experiments. Toltrazuril at 20 mg kg-1, given on Day 7 or Day 10 after turnout on pasture, proved to be highly efficacious in preventing clinical coccidiosis under Norwegian conditions. Toltrazuril reduced the oocyst output to very low levels, prevented the development of diarrhoea and improved weight gain during the first 4-5 weeks after treatment. Treatment on Day 7 was superior to treatment on Day 10 with respect to improving weight gain and preventing the development of soft faeces. Lambs treated with toltrazuril on Day 7 seemed to be as immune as untreated lambs to natural reinfections with coccidia later in the grazing season. In one of the experiments, natural infections with the nematode Nematodirus battus produced a coccidiosis-like disease in some lambs simultaneously with the outbreak of coccidiosis.     

Treatment with toltrazuril in a natural outbreak of coccidiosis in calves

Treatment with toltrazuril (Baycox) in calves naturally infected with several enteropathogenic agents resulted in a reduction in the mean number of Eimeria oocysts shed. The mean faecal consistency for the treated calves also differed significantly from that of the untreated calves. There was virtually no difference in weight gain in the two groups.     

The use of toltrazuril for the prevention of coccidiosis in piglets before weaning

SUMMARY: To determine the efficacy of toltrazuril as a prophylactic treatment for coccidiosis in piglets caused by Isospora suis (I suis) , a single 1.0 mL dose of toltrazuril was administered orally to 1056 piglets between 3 and 6 days of age, in 5 piggeries. Prophylactic treatment of piglets reduced the occurrence of coccidiosis in litters from 71% to 22%. The number of antibacterial treatments given and the number of piglets affected per litter were also significantly reduced, resulting in some improvement in growth rates to weaning. The severity of diarrhoea was significantly reduced, as was the amount of oocyst excretion. The number of days that piglets excreted oocysts in the faeces was reduced from 4.9 days to 2.5 days. The detection of J suis in piglets with diarrhoea was reduced from 84% in the untreated piglets to 6% in the piglets given the prophylactic treatment.