RNA aptamer-driven ECL biosensing for tracing histone acetylation based on nano-prism substrate and cascade DNA amplification strategy

A new RNA aptamer-involved electrochemiluminescence (ECL) strategy for sensitive detection of histone acetyltransferase (HAT p300) is designed well based on coenzyme A (CoA)-initiated competitive response and advanced DNA nano-biotechnology. For the first time, this interesting analytical process is comprised of significant histone acetylation catalyzed by HAT p300, competitive replacement triggered by the specific binding of CoA and its RNA aptamer , stable scaffold guided by DNA nano-prism and typical amplification managed by hybrid chain reaction (HCR). Upon recognition of the RNA aptamer to CoA generated in acetylation, auxiliary DNA (A-DNA) which can be captured by three hanging arms of the fabricated DNA nano-prism immobilized onto Au electrode surface is released from the aptamer/A-DNA complex. Moreover, A-DNA can also open skillfully one hairpin DNA (H1), then turning into HCR process by alternating hybridization with the other hairpin DNA (H2). Abundant Ru(phen) 3 2+ molecules which have a strong interaction with dsDNA can result in a significant output. This proposed platform exhibits excellent specificity and sensitivity toward HAT p300 with a detection limit of 0.001 nM and takes on outstanding practicality and superiority, which presents a great potential for HAT p300 analysis in biomedical sciences.