A novel self-powered biosensor is engineered by the integration of DNAzyme walker and AuNPs/graphdiyne biosensing interface, realizing sensitive detection of target microRNA. The cleverly constructed DNAzyme walker with outstanding signal transduction ability to obtain an amplified signal response. In addition, the AuNPs/graphdiyne significantly improves electron transport speed of biosensing interface for improving the sensitivity of biosensor. A dynamic linear range of 0.05 fM-10 pM with a low detection limit of 0.015 fM (S/N = 3) is obtained by utilizing the self-powered biosensor. Meanwhile, the developed self-powered biosensor is capable of assaying miRNA-21 in human serum samples with satisfactory recoveries. This strategy provides a valid method for the sensitive microRNA detection, and shows great potential in point-care detection of tumor biomarker.
Keywords: AuNPs/graphdiyne; DNAzyme walker; Self-powered biosensor; Sensitive detection; microRNA.
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