College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, China.
Xingzhi College, Zhejiang Normal University, Jinhua 321004, China.
Langmuir. 2021 Mar 30;37(12):3612-3619. doi: 10.1021/acs.langmuir.0c03593. Epub 2021 Mar 17.
Kanamycin (Kana) is widely used as a veterinary medicine and its abuse causes a serious threat to human health, raising the urgent demand for detection of residual Kana in animal-derived food with high specificity and sensitivity. Here, we developed a photoelectrochemical (PEC) biosensor for rapid quantification of Kana, with lead sulfide quantum dots/titanium dioxide nanoparticles (PbS QDs/TiO NPs) as a photosensitive composite, a Kana-specific DNA aptamer as a functional sensor, and ruthenium(III) hexaammine (Ru(NH)) as a signal booster. To prepare the PEC aptasensor, TiO NPs, PbS QDs, and polyethyleneimine (PEI) were respectively used to modify the indium tin oxide electrode, and then the amine-terminated aptamer probe was connected to the PEI via glutaraldehyde. Finally, Ru(NH) was attached on the surface of the aptamer to increase the photocurrent intensity. When Kana binds competitively with Ru(NH) to the aptamer immobilized on the surface of the aptasensor, Ru(NH) will be released from the aptamer, resulting in a decrease of the photocurrent signal. This PEC aptasensor exhibits a good linear relationship between the photocurrent shift and the logarithm of Kana concentration within the range of 1.0-300.0 nmol L, and the detection limit is 0.161 nmol L. Importantly, the PEC aptasensor presented good detection selectivity owing to specific interaction with Kana and was successfully implemented to quantify Kana in honey and milk, suggesting that the PEC aptasensor has the potential of rapid detection of residual Kana in animal-derived foods.
卡那霉素（Kana）被广泛用作兽药，其滥用对人类健康构成严重威胁，因此迫切需要具有高特异性和灵敏度的方法来检测动物源性食品中的残留卡那霉素。在这里，我们开发了一种用于快速定量卡那霉素的光电化学（PEC）生物传感器，该传感器以硫化铅量子点/二氧化钛纳米粒子（PbS QDs/TiO NPs）作为光敏复合材料，以卡那霉素特异性 DNA 适体作为功能传感器，并以钌（III）六氨合（Ru（NH））作为信号增强剂。为了制备 PEC 适体传感器，分别使用 TiO NPs、PbS QDs 和聚乙烯亚胺（PEI）来修饰氧化铟锡电极，然后通过戊二醛将氨基末端适体探针连接到 PEI 上。最后，将 Ru（NH）附着在适体的表面上以增加光电流强度。当 Kana 与固定在适体传感器表面上的 Ru（NH）竞争结合时，Ru（NH）将从适体上释放出来，从而导致光电流信号降低。该 PEC 适体传感器在 1.0-300.0 nmol L 的范围内，光电流变化与 Kana 浓度的对数之间呈现出良好的线性关系，检测限为 0.161 nmol L。重要的是，由于与 Kana 的特异性相互作用，PEC 适体传感器表现出良好的检测选择性，并成功用于定量蜂蜜和牛奶中的 Kana，表明该 PEC 适体传感器具有快速检测动物源性食品中残留 Kana 的潜力。
