Xue Jie, Gao Chaomin, Zhang Lina, Cui Kang, He Wenxing, Yu Jinghua
School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China.
J Mater Chem B. 2018 Jul 28;6(28):4697-4703. doi: 10.1039/c8tb00992a. Epub 2018 Jul 4.
In this study, a single-interface photoelectrochemical (PEC) sensor for detecting two antigens, alpha fetoprotein (AFP) and cancer antigen 153 (CA 153), was achieved based on the heterostructure of branched titanium dioxide nanorods (B-TiO NRs)@strontium titanate (SrTiO) heterostructures. The B-TiO NRs@SrTiO heterostructure, prepared by a facile hydrothermal method with the feature of enhanced photogenerated charge carrier separation properties, was first employed as a photoactive substrate for anchored analyst. In order to achieve the goal of successfully detecting two biomarkers at a single interface, the two specific enzyme tags β-galactosidase and acetylcholine esterase linked with a secondary detection antibody were utilized to catalytically hydrolyze p-aminophenyl galactopyranoside and acetylthiocholine to p-aminophenol and thiocholine, respectively. Based on the above enzyme-catalyzed reactions to produce sacrificial electron donors, the photocurrent signals generated from different analytes could be distinguished at a single interface. The results demonstrate that this single-interface PEC sensor not only provides a method for the early detection of AFP and CA 153 but also provides new insight into designing a novel PEC sensor for the detection of two biomarkers with high efficiency and a simple method of operation.
在本研究中，基于分支二氧化钛纳米棒（B-TiO NRs）@钛酸锶（SrTiO）异质结构，实现了一种用于检测两种抗原，即甲胎蛋白（AFP）和癌抗原153（CA 153）的单界面光电化学（PEC）传感器。通过简便的水热法制备的B-TiO NRs@SrTiO异质结构具有增强的光生电荷载流子分离特性，首次被用作固定分析物的光活性底物。为了实现在单个界面成功检测两种生物标志物的目标，利用与二抗连接的两种特异性酶标签β-半乳糖苷酶和乙酰胆碱酯酶分别催化水解对氨基苯基吡喃半乳糖苷和乙酰硫代胆碱生成对氨基酚和硫代胆碱。基于上述产生牺牲电子供体的酶催化反应，可以在单个界面区分不同分析物产生的光电流信号。结果表明，这种单界面PEC传感器不仅为AFP和CA 153的早期检测提供了一种方法，而且为设计一种高效检测两种生物标志物的新型PEC传感器和一种简单的操作方法提供了新的思路。
