An insertion approach electrochemical aptasensor for mucin 1 detection based on exonuclease-assisted target recycling

作者：Wen Wei; Hu Rong; Bao Ting; Zhang Xiuhua; Wang Shengfu^*

来源：Biosensors and Bioelectronics, 2015, 71: 13-17.

DOI：10.1016/j.bios.2015.04.001

• Electrochemical aptasensor
• Insertion approach
• Exonuclease
• Target recycling
• Mucin 1

In this work, a sensitive exonuclease-assisted amplification electrochemical aptasensor through insertion approach was developed for the detection of mucin 1 (MUC 1). In order to construct the aptasensor, 6-Mercapto-1-hexanol (MCH) was used to block partial sites of gold electrode (GE), followed by thiolated capture probe self-assembled on GE. Methylene blue (MB) labeled aptamer hybridized with capture probe at both ends to form double-strand DNA. For the MB labeled termini was close to GE, the electrochemical response was remarkable. The presence of MUC 1 caused the dissociation of the double-strand DNA owing to the specific recognition of aptamer to MUC 1. Then exonuclease I (Exo I) selectively digested the aptamer which bound with MUC 1, the released MUC 1 participated new binding with the rest aptamer. Insertion approach improved the reproducibility and Exo I-catalyzed target recycling improved the sensitivity of the aptasensor significantly. Under optimal experimental conditions, the proposed aptasensor had a good linear correlation ranged from 10 pM to 1 mu M with a detection limit of 4 pM (Signal to Noise ratio, S/N=3). The strategy had great potential for the simple and sensitive detection of other cancer markers.

• 出版日期2015-9-15
• 单位湖北大学