State Key Laboratory of Pharmaceutical Biotechnology and Collaborative Innovation Center of Chemistry for Life Sciences, Department of Biochemistry, Nanjing University, Nanjing, 210093, PR China; Department of Laboratory Medicine, The Second Affiliated Hospital of Southeast University, Nanjing, 210003, PR China.
School of Pharmacy, Nanjing Medical University, Nanjing, 211166, PR China.
Anal Chim Acta. 2018 Oct 5;1026:140-146. doi: 10.1016/j.aca.2018.04.015. Epub 2018 Apr 18.
A reusable biosensor has been fabricated in this work for the assay of α-glucosidase activity and the inhibitor screening. In this design, the aptamer of ATP is split as split aptamer 1 (Apt 1) and split aptamer 2 (Apt 2), and Apt 2 can link gold nanoparticles (AuNPs) modified with Apt 1 and 4-aminophenyl-α-d-glucopyranoside (pAPG). Consequently, the functional AuNPs can be immobilized onto the surface of gold electrode, allowing for salt-induced regeneration. In the presence of α-glucosidase, the glycosyl of pAPG is cut off, and the electroactive phenolic hydroxyls appear to give a strong current signal. Furthermore, the biosensor can be recovered very easily by incubating it in water to dissociate the AuNPs modified with Apt 1 and pAPG. So, a new biosensor for α-glucosidase activity detection and inhibitor screening is developed based on enzyme-activated signal generation and recovery. The biosensor may also exhibit good sensitivity for α-glucosidase determination with the detection limit 0.005 U/mL and can be reused by water-washing regeneration with good repeatability. Meanwhile this biosensor can also be utilized for inhibitor screening, which may have potential for clinical applications.
在这项工作中，我们制备了一种可重复使用的生物传感器，用于检测α-葡萄糖苷酶活性和抑制剂筛选。在这个设计中，ATP 的适体被分割为分裂适体 1（Apt 1）和分裂适体 2（Apt 2），Apt 2 可以连接修饰有 Apt 1 和 4-氨基苯-α-d-吡喃葡萄糖苷（pAPG）的金纳米粒子（AuNPs）。因此，功能化的 AuNPs 可以固定在金电极表面，允许盐诱导的再生。在α-葡萄糖苷酶存在下，pAPG 的糖苷被切断，电活性的酚羟基出现，产生强电流信号。此外，通过将生物传感器在水中孵育以解离修饰有 Apt 1 和 pAPG 的 AuNPs，可以非常容易地回收生物传感器。因此，基于酶激活信号的产生和恢复，开发了一种用于检测α-葡萄糖苷酶活性和抑制剂筛选的新型生物传感器。该生物传感器对α-葡萄糖苷酶的测定也表现出良好的灵敏度，检测限为 0.005 U/mL，并且可以通过水洗再生进行重复使用，具有良好的重复性。同时，这种生物传感器也可以用于抑制剂筛选，这可能具有临床应用的潜力。
