Electrochemical protein detection by target-responsive programmable dynamic DNA assembly

Abstract

Nucleic acid amplification is responsible for pushing the limit-of-detection of molecular diagnostic assays to unprecedented levels. We developed an assay based on protein-responsive programmable dynamic DNA assembly (PRPDA) to detect proteins via an intermediate process involving nucleic acids for taking advantage of nucleic acid amplification strategies. PRPDA has previously been designed for sensitive protein analysis in fluorescent assay formats. To further push the detection limit and to achieve assay miniaturization and multiplexing, we sought to combine PRPDA with electrochemical readout. We were able to achieve LOD of 1 pM by employing wrinkled gold electrode for the PRDA protein detection scheme. Which is 2800 times improvement compare to the 2.8 nM demonstrated by fluorescent transduction.