适配体增强金纳米粒子类过氧化物酶活性快速检测鸡蛋中的恩诺沙星

Aptamer enhanced gold nanoparticle peroxidase activity for enrofloxacin rapid detection

中文关键词:  金纳米粒子  类过氧化物酶  核酸适配体  恩诺沙星

英文关键词:gold nanoparticles  peroxidase  aptamer  enrofloxacin

中文摘要:

      目的 利用核酸适配体增强金纳米粒子类过氧化物酶(peroxidase, POD)活性, 建立了一种快速检测鸡蛋中恩诺沙星的方法。方法 金纳米粒子具有类POD活性, 能催化H2O2氧化3,3’-5,5’四甲基联苯胺(3,3’-5,5’tetramethylbenzidine, TMB)反应, 加入核酸适配体后, 适配体通过Au-N键吸附于金纳米粒子表面, 使催化活性增强; 进一步加入靶标物恩诺沙星后, 核酸适配体与靶标物特异性结合而脱离金纳米粒子表面, 使催化活性减弱。基于此建立了恩诺沙星比色检测方法, 优化了反应条件, 并将其用于鸡蛋样品检测中。结果 在核酸适配体浓度为10 nmol/L, TMB浓度为0.3 mmol/L, 显色反应时间为20 min时, 反应体系的吸光度变化随恩诺沙星浓度在5~150 ?mol/L范围内具有良好的线性关系, 检出限为1.98 ?mol/L。该方法具有良好的选择性和抗干扰能力, 将此法用于鸡蛋中的恩诺沙星的检测, 加标回收率为92.67%~109.04%。结论 该方法简便快速, 为鸡蛋中恩诺沙星检测提供了一种新的尝试方法。

英文摘要:

      Objective To establish a rapid method for the determination of enrofloxacin in egg by using aptamer to enhance the peroxidase (POD) activity of gold nanoparticles. Methods Gold nanoparticles had POD-like activity, which could catalyze the oxidation of 3,3’-5,5’ tetramethylbenzidine (TMB) with H2O2. After adding aptamer, the aptamer was adsorbed on the surface of gold nanoparticles by Au-N bond, which enhanced the catalytic activity. After further addition of the target enrofloxacin, the aptamer specifically binded to the target and leaves the surface of AuNPs, which weakened the catalytic activity. Based on this, the colorimetric detection method of enrofloxacin was established, the reaction conditions were optimized, and it was used in the detection of egg samples. Results When the concentration of aptamer was 10 nmol/L, the concentration of TMB was 0.3 mmol/L, and the color reaction time was 20 min, the absorbance change of the reaction system had a good linear relationship with the concentration of enrofloxacin in the range of 5?150 ?mol/L, and the limit of detection was 1.98 ?mol/L. This method showed good selectivity and anti-interference ability, and could be used in the detection of enrofloxacin in eggs, with the spiked recovery rate 92.67%?109.04%. Conclusion This method is simple and rapid, and provides a new attempt for the rapid detection of enrofloxacin in eggs.