基于量子点二抗偶联物的荧光免疫分析法测定牛奶中的氨苄青霉素

Determination of ampicillin in milk by fluorescence immunoassay based on quantum dot secondary antibody conjugates

中文关键词:  量子点  氨苄青霉素  牛奶  残留检测

英文关键词:quantum dots  ampicillin  milk  residue detection

中文摘要:

      目的 建立基于量子点二抗偶联物的荧光免疫分析法测定牛奶中的氨苄青霉素。方法 采用共价偶联的方法将Qdot 655红色荧光量子点(quantum dots, QDs)与二抗偶联, 利用制备好的QDs-二抗偶联物代替传统酶标二抗应用到检测牛奶中氨苄青霉素残留检测的荧光免疫分析方法中, 并将该方法与酶联免疫吸附法(enzyme linked immunosorbent assay, ELISA)和高效液相色谱法(high performance liquid chromatography, HPLC)进行比较。结果 该方法50%抑制浓度(IC50)为8.3 μg/L; 检测限为2.5 μg/L。空白牛奶加标回收率为94.0%~106.2%, 变异系数为2.1%~9.2%。在实际样品的检测中, 该方法与ELISA方法和HPLC方法测定的结果相比无显著差异(P>0.05)。结论 该方法准确、灵敏, 适用于牛奶中氨苄青霉素残留的检测。

英文摘要:

      Objective To establish a fluorescence immunoassay for the determination of ampicillin in milk based on quantum dot secondary antibody conjugates. Methods The red fluorescent quantum dots (QDs) of Qdot 655 were coupled with the secondary reactance by covalent coupling, the prepared QDs- secondary antibody conjugate was used to detect ampicillin residue in milk instead of the traditional enzyme standard secondary antibody by fluorescence immunoassay. The method was compared with enzyme linked immunosorbent assay (ELISA) and high performance liquid chromatography (HPLC). Results The 50% inhibitory concentration (IC50) of the method was 8.3 g/L, the limit of detection was 2.5 g/L. The blank milk spiked recoveries were 94.0%?106.2%, and the coefficients of variation were 2.1%?9.2%. In the detection of actual samples, the method has no significant difference compared with the results determined by ELISA and HPLC (P>0.05). Conclusion The method is accurate, sensitive, and suitable for the detection of ampicillin residues in milk.