核酸适配体-纳米金可视化检测盐酸克伦特罗

A New Method for the Determination of Clenbuterol Based on Aptamer and Gold Nanoparticles

摘要:

建立了一种基于核酸适配体识别-纳米金显色的盐酸克伦特罗可视化检测方法。通过合成纳米金、适配体、适配体互补链以及适配体-纳米金探针和互补链-纳米金探针，利用纳米金的变色效应，构建了盐酸克伦特罗的简单、快速、高灵敏度检测方法。当待测物中含有目标物时，适配体与目标物结合，纳米金呈现游离状态，在一定的盐浓度下，纳米颗粒发生聚集，纳米金颜色发生变化；当待测物中不含目标物时，适配体与适配体互补链互补杂交，形成稳定的网络结构，溶液颜色不发生变化。分别对适配体、互补链与纳米金连接的陈化盐浓度、适配体与互补链浓度、显色体系盐浓度等参数进行了优化。在优化的条件下，盐酸克伦特罗在1~1000 ng/mL浓度范围内，呈现良好的线性关系，回归方程为y=0.023 x+0.362（R2=0.991），最低检测限为1 ng/mL。对猪肝实际样品的加标回收率为83.5%~101.8%。该方法简单、准确、可靠，可用于实际样品的检测分析。

Abstract:

To detect clenbuterol (CL), a β-Agonist,a visual and rapid method based on aptamer and gold nanoparticles (AuNPs) was established in this study. The aptamer (DNA1) conjugating with clenbuterol, and its complementary DNA (DNA2) were designed and synthetized, respectively. The aptamer-AuNPs probe (probe1) and aptamer complementary DNA-AuNPs probe (probe2) were also synthetized in present study. In the presence of CL, aptamer bound to the target, AuNPs maintained a free state, however, these AuNPs began to aggregate and change color from red to purple in a high concentration of salt. In the absence of CL, aptamer and its complementary DNA formed a stable network, keeping red color. Some parameters, such as the concentration of aptamer, aptamer complementary DNA and salt were optimized, respectively. The results showed that in the optimum conditions, clenbuterol had a good linear relationship ranging from 1 to 1000 ng/mL, with correlation coefficients (R2) 0.991. The visual detection limit was 1 ng/g, and the recoveries at three spike levels ranged from 83.5% to 101.8%.This newly developed method was simple, sensitive, and reliable. It was suitable to detect clenbuterol in actual samples.