Fuel-Powered DNA Nanomachines for Biosensing and Cancer Therapy.

Inspired by biological motors, various artificial nanomachines and DNA motors have been fabricated to manipulate their motion on the nanometer scale, due to the high predictability and programmability of Watson-Crick base pairing. Among them, a fuel-powered DNA nanomachine is essentially a toehold-mediated strand exchange reaction and its driving force mainly comes from the hybridization of fuel DNA. It can be initiated by an input strand and automatically operate with the assistance of fuel DNA, realizing input strand recycle and signal amplification. Meanwhile, it is used as a carrier to load various drugs, such as Dox, siRNA and photosensitizers. Due to its excellent cellular penetrability and biocompatibility, fuel-powered DNA nanomachine usually enables operation inside living systems to execute all kinds of specific tasks according to the well-designed DNA strand displacement reaction, such as biomarker imaging, DNA computing and cancer theranostic applications. Therefore, as a catalytic amplification strategy and intelligent drug release platform, fuel-powered DNA nanomachine has attracted widespread attention in biosensors and cancer therapy. Hence, we present a Review on the design mechanism of fuel-powered DNA nanomachines and recent research advances in bioimaging and cancer therapy. It is hoped that this Review will provide the constructive direction for the design of fuel-powered DNA nanomachines and their applications in biological analysis and cancer treatment.