School of Chemistry and Chemical Engineering, Institute for Energy Research, Jiangsu University, Zhenjiang, 212013, China.
Jiangsu Key Laboratory for Environment Functional Materials, Jiangsu Key Laboratory of Intelligent Building Energy Efficiency, Suzhou University of Science and Technology, Suzhou, 215009, China.
Mikrochim Acta. 2019 Nov 1;186(11):737. doi: 10.1007/s00604-019-3856-0.
A self-powered photoelectrochemical (PEC) aptamer probe is presented for the determination of oxytetracycline (OTC). The assay is based on the use of g-CN and NiO nanocrystals (NCs) which form a heterojunction. The latter was prepared by two-step hydrothermal pyrolysis by using the ionic liquid 1-hydroxyethyl-3-methylimidazole chloride which functions as a morphological template to form NiO NCs. The heterojunction exhibits much better electronic conductivity, wider absorption range, higher electron-hole-separation productivity, and stronger photocurrent compared to plain g-CN. The heterojunction was adopted to construct a self-powered PEC aptamer probe for OTC detection. An OTC-binding aptamer was immobilized on the heterojunction and the probe was constructed. The aptamer on the probe binding with OTC can form steric hindrance for transmitting of electrons and cause the PEC signal change depending on the OTC concentration. The photocurrent decreases with increasing OTC concentration in the 0.01 to 100 nM concentration range and its detection limit is 4 pM (at S/N = 3). Graphical abstract Schematic representation of a self-powered photochemical aptamer probe. The probe performs enhanced ability for oxytetracycline (OTC) determination due to the formation of NiO nanocrystals/g-CN (NiO NCs/g-CN) heterojunction and the specification recognition of the aptamer.
一种自供电光电化学（PEC）适体探针被提出用于测定土霉素（OTC）。该测定基于使用 g-CN 和 NiO 纳米晶体（NCs）形成异质结。后者通过两步水热热解制备，使用离子液体 1-羟乙基-3-甲基咪唑氯化物作为形态模板形成 NiO NCs。与纯 g-CN 相比，异质结表现出更好的电子导电性、更宽的吸收范围、更高的电子-空穴分离生产率和更强的光电流。该异质结被用于构建用于 OTC 检测的自供电 PEC 适体探针。将 OTC 结合适体固定在异质结上并构建探针。探针上的适体与 OTC 结合会形成对电子传递的空间位阻，并且根据 OTC 浓度导致 PEC 信号变化。光电流随 OTC 浓度在 0.01 至 100 nM 浓度范围内的增加而降低，其检测限为 4 pM（S/N = 3）。
