Dual-Target Electrochemical Biosensing Based on DNA Structural Switching on Gold Nanoparticle-Decorated MoS2 Nanosheets

A MoS2-based electrochemical aptasensor has been developed for the simultaneous detection of thrombin and adenosine triphosphate (ATP) based on gold nanoparticles-decorated MoS2 (AuNPs-MoS2) nanocomposites. Two different aptamer probes labeled with redox tags were simultaneously immobilized on an AuNPs-MoS2 film modified electrode via Au-S bonds. The aptamers presented structural switches with the addition of target molecules (thrombin and ATP), resulting in methylene blue (MB) far from or ferrocene (Fc) close to the electrode surface. Therefore, a dual signaling detection strategy was developed, which featured both "signal-on" and "signal-off" elements in the detection system because of the target-induced structure switching. This proposed aptasensor could simultaneously determine ATP and thrombin as low as 0.74 nM ATP and 0.0012 nM thrombin with high selectivity, respectively. In addition, thrombin and ATP could act as inputs to activate an AND logic gate.