College of Chemistry, Green Catalysis Center, Zhengzhou University, PR China.
Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450001, PR China.
Anal Chim Acta. 2024 Aug 15;1317:342920. doi: 10.1016/j.aca.2024.342920. Epub 2024 Jun 28.
As a broad-spectrum tetracycline antibiotic, Oxytetracycline (OTC) was widely used in a variety of applications. But, the overuse of OTC had led to the detection of it in food, water and soil, which could present significance risk to human health and cause damage to ecosystem. It was of great significance to develop sensitive detection methods for OTC. Herein, an environmentally friendly photoelectrochemical (PEC) aptasensor was constructed for the sensitive detection of OTC based on CuO-induced BiOBr/AgS/PDA (Polydopamine) photocurrent polarity reversal.
BiOBr/AgS/PDA composites modified electrode not only produced stable initial anodic photocurrent but also provided attachment sites for the aptamer S1 of OTC by the strong adhesion of PDA. On the other hand, CuO loaded OTC aptamer S2 (Cu-S2) was got through Cu-S bonds. After the target OTC was identified on the electrode surface, CuO was introduced to the surface of ITO/BiOBr/AgS/PDA through the specific binding of OTC to S2. This identification process formed dual Z-type heterojunctions and resulted in a remarkable reversal of photocurrent polarity from anodic to cathodic. Under optimization conditions, the PEC aptasensor showed a wide linear range (50 fM ∼ 100 nM), low detection limit (1.9 fM), excellent selectivity, stability and reproducibility for the detection of OTC. Moreover, it was successfully used for the analysis of OTC in real samples of tap water, milk and honey, and had the potential for practical application.
This work developed an environmentally friendly photocurrent-polarity-switching PEC aptasensor with excellent selectivity, reproducibility, stability, low LOD and wide linear range for OTC detection. This sensitive system, which was including BiOBr, AgS, PDA and CuO were low toxicity, not only reduced the risk of traditional toxic semiconductors to operators and the environment, but can also be used for the detection of real samples, broadening the wider range of applications for BiOBr, AgS, PDA and CuO.
作为一种广谱四环素抗生素，土霉素（OTC）被广泛应用于各种领域。但是，由于 OTC 的过度使用，它已经在食物、水和土壤中被检测到，这对人类健康构成了重大威胁，并对生态系统造成了损害。因此，开发用于 OTC 的灵敏检测方法具有重要意义。在这里，我们构建了一种基于 CuO 诱导的 BiOBr/AgS/PDA（聚多巴胺）光电流极性反转的环保光电化学（PEC）适体传感器，用于 OTC 的灵敏检测。
BiOBr/AgS/PDA 复合材料修饰电极不仅产生稳定的初始阳极光电流，而且通过 PDA 的强粘附作用为 OTC 的适体 S1 提供了附着位点。另一方面，通过 Cu-S 键得到负载 OTC 适体 S2（Cu-S2）的 CuO。在电极表面识别出目标 OTC 后，通过 OTC 与 S2 的特异性结合，将 CuO 引入到 ITO/BiOBr/AgS/PDA 表面。这个识别过程形成了双 Z 型异质结，导致光电流极性从阳极到阴极发生显著反转。在优化条件下，PEC 适体传感器对 OTC 的检测表现出宽的线性范围（50 fM ～ 100 nM）、低检测限（1.9 fM）、优异的选择性、稳定性和重现性。此外，它还成功地用于自来水、牛奶和蜂蜜等实际样品中 OTC 的分析，具有实际应用的潜力。
本工作开发了一种环保的光电化学适体传感器，具有出色的选择性、重现性、稳定性、低检测限和宽线性范围，用于 OTC 的检测。该灵敏系统包括 BiOBr、AgS、PDA 和 CuO，毒性较低，不仅降低了传统有毒半导体对操作人员和环境的风险，而且还可用于真实样品的检测，拓宽了 BiOBr、AgS、PDA 和 CuO 的应用范围。
