DNA circuits as amplifiers for the detection of nucleic acids on a paperfluidic platform

Abstract

This article describes the use of non-enzymatic nucleic acid circuits based on strand exchange reactions to detect target sequences on a paperfluidic platform. The DNA circuits that were implemented include a non-enzymatic amplifier and transduction to a fluorescent reporter; these yield an order of magnitude improvement in detection of an input nucleic acid signal. To further improve signal amplification and detection, we integrated the enzyme-free amplifier with loop-mediated isothermal amplification (LAMP). By bridging the gap between the low concentrations of LAMP amplicons and the limits of fluorescence detection, the non-enzymatic amplifier allowed us to detect as few as 1,200 input templates in a paperfluidic format.

Point-of-Care Diagnostics

“…1.2e). Another paper-based platform involving fluorescent sensing described the use of non-enzymatic nucleic acid circuits based on strand exchange reactions for the detection of target sequences [135]. Overall, although fluorescence sensing brings new capabilities to point-of-care diagnostics, the feasibility requires reduction in cost and miniaturisation of fluorescence readers.…”

Lab-on-a-Chip Devices and Micro-Total Analysis Systems

“…Here, the detection was performed in the following steps: (1) targeting DNA promoted ligation of a DNA primer to the microgel-bound DNA, (2) rolling circle amplification (RCA) between the primer and a circle DNA, and (3) hybridization of the RCA products and fluorescent DNA probe. Fluorescent sensing paper devices have also utilised non-enzymatic nucleic acid circuits based on strandexchange reaction for the detection of target sequences (Allen et al 2012).…”

Open source and DIY hardware for DNA nanotechnology labs

“…Increasingly functional examples include precise nanometer scale devices such as an engineered nanopore [9] and a locked box that opens in response to an input oligonucleotide [10]. Some practical applications have also emerged including signal amplification [11] and transduction [12]. …”