应用胶体金免疫层析法检测饲料中恩拉霉素残留的方法建立

A colloidal gold immunochromatography-based method for detecting enramycin residues in feed

摘要:

为了实现饲料中恩拉霉素的快速检测，本研究开发了基于抗恩拉霉素A单克隆抗体(anti-enramycin A monoclonal antibody, anti-Er.A-mAb)的竞争抑制胶体金免疫层析试纸条。以实验室制备的高纯度抗恩拉霉素A单克隆抗体制备胶体金探针，并考察了标记pH、抗体标记量、检测线浓度对恩拉霉素胶体金免疫层析试纸条的影响。在碳酸钾添加量为8 μL、抗体标记量为4 μg/mL、检测线划膜浓度为1.0 mg/mL、金标抗体使用量为3 μL的条件下制备得到的胶体金试纸条特异性好、检出限低。经胶体金读数仪测定，恩拉霉素A检出限为25 ng/mL、线性范围为25-300 ng/mL。选用畜禽饲料进行阳性样本添加实验，结果显示检测结果重复性好，比高效液相色谱法更为灵敏，适合大批量饲料样本的恩拉霉素快速检测。

Abstract:

To achieve rapid detection of enramycin in feed, we employed the competitive inhibition method to develop a colloidal gold immunochromatographic test strip based on the anti-enramycin A monoclonal antibody (anti-Er.A-mAb). Colloidal gold probes were prepared with a laboratory-prepared high-purity anti-Er.A-mAb. The effects of pH, antibody titer, and antigen concentration (test line) on the test strip performance were investigated. The colloidal gold test strip prepared with 8 μL potassium carbonate addition, 4 μg/mL antibody, 1.0 mg/mL antigen (test line), and 3 μL gold-labeled antibody showed acceptable specificity and a low limit of detection. The test strip showed the detection limit of 25 ng/mL for enramycin A, with a linear range of 25–300 ng/mL. The experiments on the feed with positive sample addition proved that the test strip had good repeatability and was more sensitive than high-performance liquid chromatography, being applicable for the rapid detection of enramycin in large batches of feed samples.