Bi-enzyme functionlized hollow PtCo nanochains as labels for an electrochemical aptasensor

作者：Bai, Lijuan; Yuan, Ruo^*; Chai, Yaqin; Yuan, Yali; Zhuo, Ying; Mao, Li

来源：Biosensors and Bioelectronics, 2011, 26(11): 4331-4336.

DOI：10.1016/j.bios.2011.04.032

• Hollow PtCo nanochains
• Bi-enzyme
• Amplification
• Electrochemical aptasensor
• Thrombin

In this work, a new signal amplification strategy based on hollow PtCo nanochains (HPtCoNCs) functionalized by bi-enzyme-horseradish peroxidase mimicking DNAzyme (HRP-DNAzyme) and glucose oxidase (GOD), as well as ferrocene-labeled secondary thrombin aptamer (Fc-TBA 2), is developed to construct a highly sensitive electrochemical aptasensor. The HRP-DNAzyme contains a special G-quadruplex structure with an intercalated hemin. With the surface area enlarged by HPtCoNCs, the amount of immobilized Fc-TBA 2, hemin and GOD can be enhanced. Under the enzyme catalysis of GOD, D-glucose is rapidly oxidized into gluconic acid accompanying with the generation of H2O2, which is further electrocatalyzed by Pt nanoparticles and HPR-DNAzyme to improve the electrochemical signal of Fc. With several amplification factors mentioned above, a wide linear ranged from 0.001 to 30 nM is acquired with a relatively low detection limit of 0.39 pM for thrombin. The present work demonstrates that using HPtCoNCs as labels is a promising way to amplify the analysis signal and improve the sensitivity of aptasensors.

• 出版日期2011-7-15
• 单位西南大学