Sensitive and selective electrochemical aptasensor via diazonium-coupling reaction for label free determination of oxytetracycline in milk samples
Sensitive and selective electrochemical aptasensor via diazonium-coupling reaction for label free determination of oxytetracycline in milk samples
复制标题
通过重氮偶联反应的灵敏选择性电化学适体传感器，用于无标记测定牛奶样品中的土霉素
DOI：
10.1016/j.snr.2020.100009
复制
发表时间：
2020-11-01
影响因子：
5.9
通讯作者：
Fang, Guozhen
中科院分区：
文献类型：
--
作者：
Yang, Yukun;Yan, Wenyan;Fang, Guozhen
土霉素作为四环素类抗生素的一种，在动物源性食品中的残留会严重危害人类健康。虽然用于OTC检测的适配器已被广泛报道，但成本低、制备简单、适用性好的无标记电化学适配器仍需进一步探索，以满足当前的迫切需求。本研究设计了一种用于土霉素检测的无标记电化学适体传感器。该检测方法基于重氮偶合反应共价结合在传感界面上的适体的特异性识别，并通过计算机模拟验证。实验结果表明，所构建的电化学适配器的微分脉冲伏安（DPV）电流响应与土霉素浓度的对数在1.0 × 10（-9）g mL（-1）~ 1.0 × 10（-4）g mL（-1）范围内呈线性关系（R-2 = 0.9897），检测限为2.29 × 10（-10）g mL（-1）。该适体传感器具有良好的选择性、重现性和稳定性，这可能归因于适体在传感界面上的稳定修饰。采用加标回收率法对牛奶样品中的土霉素进行检测，结果良好，回收率为87.0%~ 99.3%。该无标记电化学适体传感器可为抗生素残留的低成本、准确、快速检测提供新的方法。
As one kind of tetracycline antibiotics, oxytetracycline (OTC) residues in animal-derived foods can do serious harm to human health. Though aptasensors for the detection of OTC are widely reported, label-free electrochemical aptasensor with low cost, simple preparation and good applicability should be further explored to meet the current urgent needs. In this study, a label-free electrochemical aptasensor for OTC determination was designed. The detection was based on specific recognition by the aptamer covalently-bound on the sensing interface via diazonium coupling reaction, which was verified by computer simulation. Experiment results showed that the differential pulse voltammetry (DPV) current response of the constructed electrochemical aptasensor was linear with the logarithm of OTC concentration in the range of 1.0 x 10(-9) g mL(-1)1.0 x 10(-4) g mL(-1) (R-2 = 0.9897) with the limit of detection of 2.29 x 10(-10) g mL(-1). The proposed aptasensor indicated good selectivity, reproducibility and stability, which could be attributed to the stable modification of aptamer on the sensing interface. The OTC in the milk sample was detected by the spiked recovery method, and good results were obtained, with the recovery rate being 87.0%-99.3%. The proposed label-free electrochemical aptasensor can provide methods for low-cost, accurate and rapid detection of antibiotic residues.