Target-activated DNA Nanomachine for ATP detection based on SERS of plasmonic coupling from gold nanoparticles aggregation
The self-assembly plasmonic nanoparticles provides a powerful approach to generate surface-enhanced Raman scattering (SERS), which promotes the actual applications in chemical and biomolecular analysis. Herein, we have developed a facile SERS sensing strategy for ATP assay with 3-D DNA Nanomachine that walks by the Exo III cleavage leading to the formation of AuNPs aggregates, which brought the enhancement of the electromagnetic field. Depending on the target-activated and Exo III cleavage, the 3-D Nanomachine can walk along the 3-D track on the surface of AuNPs and generate self-assembled hot-spots to enhance the SERS signal of Raman dye, allowing homogenous assay of ATP concentration with high sensitivity and reproducibility. Under optimized experimental conditions, the biosensor detects ATP with a widened dynamic range from 1 pM to 1×105 pM the limit of detection up to 0.29 pM. Hence, the novel strategy provides a useful and practical platform for SERS assay of ATP with high sensitivity and repeatability. Besides, this platform also owns great potential to be applied to high throughput assays for drug screening and clinical diagnostics.