液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量的不确定度评估

采用液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量,对标准溶液、体积、质谱峰面积、浓缩过程及回收率等测定不确定度因素进行了分析,通过评定各不确定度分量及标准不确定度,得出11种β-受体激动剂的扩展不确定度在0.7 ～ 1.1 ng/mL范围内.由各因素对合成不确定度的贡献比分析可知,影响较大的因素为试验回收率及标准溶液浓度.     

液相色谱-串联质谱法测定猪肉中四环素类药物残留量的不确定度评定

评定液相色谱-串联质谱法（LC-MS/MS）测定猪肉中四环素类药物残留量的不确定度。依据GB/T 21317-2007《动物源性食品中四环素类兽药残留量检测方法 液相色谱-质谱/质谱法与高效液相色谱法》,建立相关数学模型,对实验过程中的不确定度来源进行分析与评定。当采用LC-MS/MS法测定猪肉中土霉素、四环素、金霉素、强力霉素的残留量分别为50.05、42.81、42.45、41.60μg/kg时,扩展不确定度分别为 5.44、6.72、2.86、4.80μg/kg (k=2)。检测结果的不确定度主要受回收率、标准溶液配制、工作曲线拟合的影响。     

高效液相色谱法测定牛奶中四环素残留量的不确定度评定

建立了高效液相色谱法测定牛奶中四环素残留量的不确定度评定的数学模型.通过对测量过程中的不确定度来源进行分析与评定,当残留量为85.3 μg/kg时,求得扩展不确定度为5.0μg/kg(k=2).结果表明,标准溶液配制、重复性测量、定容体积和回收率引入的不确定度为测量结果不确定度的主要影响因素.     

液相色谱法测定饲料中苏丹红残留量的不确定度研究

介绍一种饲料中苏丹红残留量测定的不确定度分析方法。对影响饲料中苏丹红残留量测定不确定度的因素进行分析,包括标准品浓度、体积、样品质量、回收率的重复性等因素,计算得出试验中4种苏丹红(I～IV)测定结果的扩展不确定度分别为0.026、0.060、0.047和0.052mg/kg。     

液质联用法测定猪肝中β-受体激动剂残留的不确定度评定

采用超高效液相色谱-串联质谱法(UPLC-MS/MS)测定猪肝中9种β-受体激动剂残留量,对标准溶液、标准曲线、样品称量、称量重复性、定容体积等因素进行分析,通过评定各不确定度分量及标准不确定度,得出9种β-受体激动剂的合成相对标准不确定度为5.60%~8.90%,影响较大的因素为标准曲线和测量重复性。     

高效液相色谱-串联质谱法测定鸡肉中癸氧喹酯残留量的测量不确定度评定

分析了影响应用高效液相色谱-串联质谱法测定鸡肉中癸氧喹酯残留量的测量不确定因素,并对各不确定度分量进行了量化计算,最终求得扩展不确定度为0.51礸/kg,分析表明重复测量、制备标准溶液及内标溶液引入的不确定度分量是影响癸氧喹酯残留量测量不确定度的主要因素。     

液相色谱法测定饲料中巴氯芬残留量的不确定度评估

本文采用液相色谱法对饲料中巴氯芬残留量的不确定度进行评估,根据《测量不确定度评定与表示》等有关规定,建立数学模型,对试样的称量、标准溶液的配制、样品浓缩、标准品和样品的峰面积以及样品回收率等影响因素进行了评定,并对测量结果的不确定度来源进行量化,计算合成不确定度,得出本次含量测定的扩展不确定度为0.099mg/kg。     

高效液相色谱-串联质谱法测定鸡肉中癸氧喹酯的测量不确定度评定

分析了影响应用高效液相色谱-串联质谱法测定鸡肉中癸氧喹酯残留量的测量不确定因素,并对各不确定度分量进行了量化计算,最终求得扩展不确定度为0.56μg/kg,分析表明重复测量、制备标准溶液及内标溶液引入的不确定度分量是影响癸氧喹酯残留量测量不确定度的主要因素。     

酶联免疫吸附分析法测定猪、鸡粪便中11种β2–受体激动剂残留的不确定度评定

以市售β_2–受体激动剂酶联免疫检测试剂盒为基础,对采用酶联免疫吸附分析法测定猪、鸡粪便中11种β_2–受体激动剂残留的不确定度进行评估,找到影响不确定度的主要因素,为控制实验过程和评价检测结果可靠性提供依据。本研究对标准溶液配制、样品称量、样品前处理过程、样品添加回收率、酶联免疫吸附分析测试程序、酶标仪吸光度示值误差等测量不确定度来源进行了分析,通过评定各不确定度分量与不确定度大小,得到猪、鸡粪便中11种β_2–受体激动剂扩展不确定度的范围分别在0.25~2.4 ng/g和0.42~1.7 ng/g范围内。由各因素对合成不确定度贡献比的分析可知,标准溶液配制、样品前处理过程、样品添加回收率、酶联免疫吸附分析测试程序、酶标仪吸光度示值误差是主要的影响因素。通过合理地控制各影响因素有利于提高检测结果的准确性与可靠性。     

高效液相色谱法测定鸡蛋中氟苯尼考残留量的不确定度研究

通过数学模型,对DB34/T 1376-2011HPLC法测定鸡蛋中氟苯尼考残留量的方法不确定度进行评估。从影响不确定度的标准溶液配制u_s、样品的前处理u_p、仪器测量的不确定度u_m三个主要因素,对不确定度分量进行计算合成。结果表明,该方法在本实验室的合成相对标准不确定度为u_x=0.028 8,k=2。     

Residue Detection of Tetracyclines in Eggs by High Performance Liquid Chromatography

The study was aimed to establish the method of simultaneous detection of four kinds of tetracyclines,including oxytraoycline,tetracycline,chlortetracycline and doxyeycline in eggs by high performance liquid chromatography (HPLC).The eggs samples were detected with HPLC after through the procedure of extraction of 0.1 mol/L Na₂EDTA-Mcllvaine buffered solution,purification of Oasis MAX solid-phase extraction column,gradient elution of taking acetonitrile-0.01 mol/mL trifluoroacetic acid as mobile phase,separation with reverse liquid chromatography.The results showed that the calibration curves of four kinds of tetracyclines were linear correlated in the concentration range of 30 to 1 000 ng/g which the limits of detection was 10 ng/g and the limit of quantification was 50 ng/g.The average recoveries were 67.3% to 81.4%,relative standard deviations of intraday was 2.7% to 14.3%,relative standard deviations of inter-day was 0.9% to 5.0%.This mothod established in this study could simultaneously detect oxytetracycline,tetracycline,chlortetracycline and doxycycline drug residues in egg and it had high sensitivity,accuracy and precision.The method was rapid and simple to operate.     

高效液相色谱法检测饲料中四环素类药物含量研究进展

对饲料中4种四环素类药物(土霉素、四环素、金霉素、强力霉素)的高效液相色谱检测方法进行了分析和总结,并探讨了不同流动相、提取溶剂、净化方式的优点和缺点。     

Development of Colloidal Gold Rapid Detection Method of β-lactams and Tetracyclines in Milk

Colloidal gold immunochromatographic was uesd for the determination of β-lactams and tetracyclines in milk. Tetracyclines hapten was obtained by chemical synthesis. Immunogen and envelope antigen were prepared by cephalosporins and tetracyclines hapten coupled to carrier protein. Monoclonal antibodies were obtained by immunogen immunizing mice. A rapid and simple colloidal gold immunochromatographic assay was established for the determination of β-lactams and tetracyclines in milk. 12 kinds of β-lactams and 4 kinds of tetracyclines were detected at the same time by the strip. The milk sample could be used to be detected without dilution. The detection time could be 3 to 5 min. The method could be efficiently used for mass samples screening in primary laboratory.     

鲫鱼弗氏柠檬酸杆菌的耐药表型及耐药基因检测

为了检测鲫鱼费氏柠檬酸杆菌的耐药表型及耐药基因,试验采用标准Kirby-Bauer纸片扩散法检测鲫鱼弗氏柠檬酸杆菌对13种抗生素的耐药表型,并用PCR法检测弗氏柠檬酸杆菌对四环素类和磺胺类抗生素的6种耐药基因(tetA、tetC、tetM、Sul1、Sul2和Sul3)。结果表明:鲫鱼弗氏柠檬酸杆菌对四环素、氨苄西林、强力霉素、红霉素、头孢拉定和阿莫西林耐药;仅检测出四环素类的tetA和tetM基因,而其他未检测出。     

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。     

HPLC-PDA法测定兽药中非法添加四种解热镇痛抗炎类药物

建立了7种兽药中非法添加对乙酰氨基酚、安乃近、地塞米松和地塞米松磷酸钠药物的HPLC-PDA法。采用十八烷基键合硅胶为填充剂,磷酸二氢钠缓冲液（磷酸二氢钠3．0 g加水至1000 mL,加三乙胺1 mL,用氢氧化钠调pH值至7．0±0．2）-甲醇（80∶20）为流动相,梯度洗脱,二极管阵列检测器进行全扫描和240 nm波长测定,并采用峰纯度检查和光谱相似度检查辅助对照品比对方法,对四种目标分析物进行确证。结果显示,4种解热镇痛抗炎药物与其他物质峰分离良好,在测定范围内线性关系良好,平均回收率为73．5％～119．2％,RSD为0．1％～5．8％。本方法准确、可靠、重现性好,可用于兽药制剂中非法添加四种解热镇痛抗炎药物的定性和定量检测。     

Enzyme-linked immunosorbent assay for screening the plasma residues of tetracycline antibiotics in pigs.

The recommended therapeutic doses of three kinds of tetracyclines, oxytetracycline (OTC, withdrawal period, 10 days), chlortetracycline (CTC, withdrawal period, 5 days) and tetracycline (TC, withdrawal period, 5 days), were each administered to a group of 15 pigs. Blood was sampled before drug administration and during the withdrawal period. The concentration of tetracyclines in plasma, determined by semi-quantitative ELISA, was compared with that of internal standard (10 ppb as oxytetracycline). The absorbance ratio of internal standard to sample (B/Bs) was employed as an index to determine the tissue residues in pigs. All 45 plasma samples from nontreated pigs showed negative in the residue of any of three tetracycline antibiotics. OTC was detected in plasma of pigs treated until the 8th day, CTC until the 4th day, and TC was detected until the 3rd day of its withdrawal period. The present study showed that the semi-quantitative ELISA easily be adopted in predicting tissue residues for tetracycline antibiotics in live pigs.     

LC-MS/MS法分析生猪异位发酵床垫料中5大类兽用抗菌药物残留及蓄积趋势

建立了生猪异位发酵床垫料中四环素类、喹诺酮类、磺胺类、酰胺醇类和大环内酯类共54种抗菌药物残留量的LC-MS/MS检测方法,经超低温冷冻粉碎后的垫料样本,以费休氏-库仑滴定法测定水分,用Mcllvaine-Na2EDTA缓冲液和乙腈提取,经亲水亲脂平衡固相萃取小柱净化,用LC-MS/MS法测定抗菌药物残留量,最终结果以折水后含量表示。方法具有简便、高通量、抗干扰的特点,可以满足生猪异位发酵床垫料中主要兽用抗菌药物残留检测的要求。利用该方法,对12家养殖场垫料样本中5大类兽用抗菌药物的残留量进行了检测。12家养殖场垫料样本中共检出25种抗菌药物,各场垫料样本抗菌药物总残留量在0.7 g/t~28 g/t之间,其中四环素类药物对总残留量的贡献率在91.3%～98.8%之间。     

Study on the Effect of Different Holly bark Extracts Combined with Western Medicine on ESBLs-producing Bacterial

This research was aimed to investigate four kinds of Holly bark extracts combined with antimicrobial drugs to induce bacteria in vitro antibacterial activity. Four kinds of Holly bark extracts were prepared, the bacterial passage of drug-resistant Escherichia coli induced by Holly bark extracts combined with antimicrobial drugs were tested by 96-well reaction plate twice micro-dilution method. Four kinds of Holly bark extracts combined with antimicrobial drugs to induce bacteria passage for drug-resistant Escherichia coli had different antibacterial activities, in which extractsⅠ,Ⅲ combination with antimicrobial drugs had the best effect. Holly bark extracts Ⅰ,Ⅲ combined with antimicrobial drugs to induce bacterial passage had anti-drug-resistant bacteria effect in vitro.