【摘要】 目的:优化建立渗滤式(Flow through)和侧流式(Lateral flow)两种金标记免疫竞争快速筛选方法。方法:采用柠檬酸三钠还原法制备胶体金,标记氯霉素多克隆抗体,以硝酸纤维素膜为载体,包被氯霉素半抗原与卵清蛋白的偶联物作为检测带,经过竞争反应后目测结果。结果:通过简单的样品前处理方法,消除了基质影响,可成功用于猪肉、鸡肉和鳕鱼样品中痕量氯霉素残留的快速检测。检测标准溶液及组织试样的提取稀释液时,灵敏度分别为0.8μg/L和1μg/L。几种氯霉素的结构类似物及常见兽药对氯霉素检测均无干扰,通过酶联免疫吸附定量检测方法验证了2种快速筛选方法的有效性,加速稳定性试验证明渗滤式金标试纸条在4℃下6个月内可保持检测结果的可靠性。结论:所建立的方法操作简单,快速,灵敏度高,稳定性好,可作为动物源性食品中氯霉素残留现场大量筛选的有效手段。更多还原

【Abstract】 Objective: Based on the principle of competitive immunoassay, flow through and lateral flow colloidal gold-labled test strips were established for the rapid on-site detection of chloramphenicol(CAP) residues. Methods: Colloidal gold was obtained by reducing the gold chloride with sodium citrate, and labeled to an anti-CAP polyclonal antibody (PAb). CAP was conjugated to ovalbumin (OVA) and coated on a nitrocellulose (NC) membrane as the test zone. The analyte in the samples competed with the immobilized CAP conjugate in the test zone for binding the gold colloidal-labeled antibody. The more analyte present in the sample,the more effectively it would compete with the CAP-OVA for binding to the limited amount of gold-labeled anti-CAP PAb, less color presented. Results: When measuring the standard solution or the diluted extraction of chloramphenicol, visual detection limits of flow through and lateral flow were 0.8 μg/L and 1 μg/L, respectively. CAP residues in pork, chicken and codfish samples were detected. The validations of the two kinds of strips were tested by ELISA. The cross-reaction studies indicated the specificity of the developed assay to CAP. The stability test indicated that the reliability of Flow through strips was good at 4 ℃ within 6 months. Conclusion: The stability, simplicity and sensitivity make it feasible to the rapid on site determination of the CAP residues in animal derived food.更多还原