HPLC-MS/MS检测双黄连注射液中非法添加13种喹诺酮类药物的研究

建立了高效液相色谱-串联质谱法检测兽用中药制剂双黄连注射液中非法添加13种喹诺酮类药物的方法。样品经0.2%甲酸溶液溶解后稀释,以0.2%甲酸溶液与甲醇作为流动相进行梯度洗脱,采用多反应监测模式进行测定。13种喹诺酮类药物检测限(LOD)为0.1~0.5 mg/m L,定量限(LOQ)为1~5 mg/m L,在5.0~200 ng/m L范围内线性关系良好,相关系数均大于0.99,在5、10、20 mg/m L三个添加浓度下,平均回收率为90.9%~101.9%,相对标准偏差为0.6%~3.8%。     

液质联用法测定水产品中喹诺酮类药物残留量的不确定度评定

文章建立了液质联用法检测水产品中喹诺酮类药物残留量结果的不确定度评估数学模型,对测量过程中的不确定度来源进行分析评定,计算各不确定度分量、相对合成不确定度和扩展不确定度,得到喹诺酮类药物的不确定度报告。分析结果显示,该测量过程产生的不确定度主要来源于液质联用仪和标准工作液配置引入的不确定度。     

高效毛细管电泳法分离检测鸡蛋中3种喹诺酮类抗菌药

旨在建立高效毛细管电泳检测鸡蛋中环丙沙星、氧氟沙星和恩诺沙星3种喹诺酮类抗生素的测定方法。研究结果显示,高效毛细管电泳在检测波长为280 nm时,最佳电泳条件是缓冲液为pH 8.53的30 mmol/L Na₂B₄O7-10 mmol/L KH₂PO₄溶液,分离电压为18 kV,温度为25 ℃。在此最佳电泳条件下,3种抗生素在12 min内实现基线分离,且各组分质量浓度与峰面积呈良好的线性关系（r＞0.996 9）,相对标准偏差（RSD）小于3%,平均加标回收率为115.92%~131.77%。该方法快速简便、灵敏度高、重现性好,可用于鸡蛋中喹诺酮类抗生素质量浓度的测定。     

食品中(氟)喹诺酮类兽药多残留检测技术的应用与发展

喹诺酮类兽药在食品中的残留问题引起各国的重视,建立高效灵敏的多残留检测方法是喹诺酮类兽药检测方法研究的热点和趋势。通过对微生物抑制法、色谱法、免疫法、蛋白芯片法在多残留检测技术的解析,概述食品中喹诺酮类药物多残留检测技术的应用现状与发展,为开展药物残留检测的研究和监测提供借鉴。     

Isolation and molecular characterization of quinolone resistant Salmonella spp. from poultry farms

The antimicrobial susceptibility of 94 Salmonella strains isolated from different poultry farms in Chile (broiler and laggin hens) were analyzed by the dilution plates method. Thirty-nine of them were resistant to flumequine, nalidixic acid and oxolinic acid with MIC values higher than 64 μg/ml. These quinolone resistant strains were analyzed in order to determine the presence of mutations in the QRDR region of gyrA gene by AS-PCR-RFLP analysis. 51.3% of the strains showed mutations at codon Ser 83 and 41.0% showed mutations at codon Asp 87. No mutations were observed on codon Gly 81. These mutations were confirmed by sequenciation of one representative strain from different RFLP pattern. Likewise, no double mutations were observed. Over 90% of the quinolone resistant strains presented mutations at the QRDR region of the gyrA gene. Three phenotypically resistant strains did not show any mutations on the QRDR region of gyrA gene. However, other molecular resistant mechanism could be involve. This is the first study that demonstrate the emergency of quinolone and fluoroquinolone resistance in Chilean Salmonella strains isolated from poultry thus indicating the requirement of monitoring programmes in veterinary medicine.     

Urban birds: An important source of antimicrobial resistant Salmonella strains in Central Spain

Antimicrobial resistance (AMR) is one of the most important threats of the 21 st century. Wild birds have been described as reservoirs of AMR in different bacterial species, such as Salmonella spp. Privation of food, climate change and overpopulation have forced many wild species to modify their feeding habits, attending urban areas. In this context, the aim of this study was to study Salmonella presence, as well as related AMR in urban birds that inhabit the city and its surroundings. A total of 300 urban birds were sampled for Salmonella detection according to the ISO 6579-1:2017 (Annex D) recommendations, and serotyping was carried out according to the White-Kauffman-Le Minor scheme. Antimicrobial susceptibility was tested following 2013/652/EU Decision guides. Wild birds analysed were positive for Salmonella in 12.3 % of cases, with white storks fed in landfills as the most Salmonella prevalent species (p < 0.05). The most common serovars isolated were zoonotic (S. Enteritidis, S. Typhimurium and S. Typhimurium monophasic variant). From Salmonella isolated strains, 40.5 % were resistant to the most prevalent AMRs found in urban birds were ciprofloxacin (36.4 %), nalidixic acid (36.4 %) and colistin (27.3 %). The scientific community, public administration and population in general should work together to control antimicrobial administration and drug waste management in order to decrease the development and spread of AMR.     

高效液相色谱法检测海水养殖环境中喹诺酮类药物残留

建立了一种养殖海水中诺氟沙星、环丙沙星和恩诺沙星3种喹诺酮类抗生素残留量的高效液相色谱-荧光测定方法。水样经稀盐酸调pH后经HLB固相萃取柱富集、净化,用外标法定量。结果表明,诺氟沙星、环丙沙星和恩诺沙星检出限分别是2、1和1μg/L,定量限分别是6.6、3.3和3.3μg/L,添加浓度为10、20和50μg/L时,3种物质的回收率为71.9%～85.3%,批内变异系数≤10%,批间变异系数≤7%。利用该方法对黄海沿岸部分养殖场及近岸海水(北起36°40.303′N,121°8.939′E;南至35°39.36′N,119°52.433′E)进行分析,诺氟沙星、环丙沙星、恩诺沙星的检出质量浓度分别为6.20～982、55.2和11.6～55.4μg/L。实验结果表明,该方法灵敏度高,重现性好,适用于养殖海水中诺氟沙星、环丙沙星和恩诺沙星的检测。     

Molecular characterization of quinolone resistance mechanisms and extended-spectrum β-lactamase production in Escherichia coli isolated from dogs

The increasing prevalence of antimicrobial resistances is now a worldwide problem. Investigating the mechanisms by which pets harboring resistant strains may receive and/or transfer resistance determinants is essential to better understanding how owners and pets can interact safely. Here, we characterized the genetic determinants conferring resistance to β-lactams and quinolones in 38 multidrug-resistant Escherichia coli isolated from fecal samples of dogs, through PCR and sequencing. The most frequent genotype included the β-lactamase groups TEM (n = 5), and both TEM + CTX-M-1 (n = 5). Within the CTX-M group, we identified the genes CTX-M-32, CTX-M-1, CTX-M-15, CTX-M-55/79, CTX-M-14 and CTX-M-2/44. Thirty isolates resistant to ciprofloxacin presented two mutations in the gyrA gene and one or two mutations in the parC gene. A mutation in gyrA (reported here for the first time), due to a transversion and transition (TCG → GTG) originating a substitution of a serine by a valine in position 83 was also detected. The plasmid-encoded quinolone resistance gene, qnrs1, was detected in three isolates. Dogs can be a reservoir of genetic determinants conferring antimicrobial resistance and thus may play an important role in the spread of antimicrobial resistance to humans and other co-habitant animals.     

生物膜干涉技术快速定性检测牛乳中喹诺酮类药物残留

[目的]基于生物膜干涉技术建立一种快速检测牛乳中喹诺酮类抗生素残留的方法。[方法]通过疏水作用力在APS光线生物传感器探头末端固定环丙沙星-BSA偶联物,结合纳米金-喹诺酮类抗生素单克隆抗体偶联物,建立了检测牛乳中喹诺酮类抗生素的方法。[结果]所建立的检测方法具有良好的灵敏度,比免疫层析法至少高出1倍。该检测方法还具有良好的特异性．与浓度1000ng／ml的黄曲霉毒素M1、青霉素G、头孢噻呋、庆大霉素、卡那霉素、链霉素、泰乐菌素、氯霉素、三聚氰胺无交叉反应。该方法还具有良好的重复性,不同基质牛乳检测对检测结果无显著影响。分别采用免疫层析试纸条和建立的金标记BLI检测方法检测43份牛乳（原奶）样品中的喹诺酮类抗生素残留,二者检测结果一致。[结论]生物膜干涉技术检测牛乳中的喹诺酮类抗生素为一种简便、快捷的检测方法,可以用于牛乳中喹诺酮类抗生素残留的快速定性检测。     

济宁市售淡水鱼中喹诺酮类抗生素残留及其健康风险评价

[目的]了解济宁市区市售淡水养殖鱼的抗生素残留水平,评价其对人体的健康风险.[方法]于2013年3～5月采集济宁市区2个农贸市场和2个大型超市鲫鱼、鲤鱼和乌鳢3种淡水养殖鱼.使用高效液相色谱法检测其肌肉与肝脏组织中的恩诺沙星(Enrofloxacin,ENFX)、环丙沙星(Ciprofloxacin,CPFX)残留的含量,并使用恩诺沙星的ADI对其进行健康风险评价.[结果]恩诺沙星在鱼肉中的检出率为83％,残留范围为0～ 76.6 ng/g,平均含量为18.36ng/g.环丙沙星在鱼肉中的检出率为25％,残留范围为0～8.4 ng/g,平均含量为6.65 ng/g.在肝脏中,恩诺沙星的检出率为83％,残留范围为0～160.1 ng/g,平均含量为34.2 ng/g.[结论]所有鱼肉样品中2种喹诺酮的含量均符合国家标准.使用恩诺沙星ADI值评价膳食安全的结果表明,恩诺沙星在鱼肉中的残留没有健康风险.