Ratiometric DNA Walking Machine for Accurate and Amplified Bioassay.

Ratiometric DNA Walking Machine for Accurate and Amplified Bioassay. Chemistry. 2019 Jul 07;: Authors: Wang C, Hu J, Lv Y, Liu R Abstract DNA walking machines opened new avenues for the biosensing and demonstrated great success in the past few years. Since DNA machines are mainly non-equilibrium systems driven by dynamic interactions, the matrix effects on DNA machines is a bottleneck and more intricated than common DNA-mediated assays, especially for complicated physiological samples. Herein, to realize an accurate and reliable quantitative machine, a ratiometric DNA walking machine was developed in human serums and cell lysates based on the elemental isotope ratio measurement. The target DNA-triggered walking machine converted and amplified biological signals into mass spectrometric signal ratios (197Au/115In) via a burnt-bridge mechanism. Under the optimized conditions, the limit of detection (LOD, 3σ) was 8 fM for target DNA, with a dynamic linear range of 50-700 fM. The ratiometric DNA walking machine was directly applied in human serum samples with satisfactory recoveries of 94% to 105%, demonstrating an excellent stability and a high accuracy. Combining the aptamer-based specific recognition, the proposed DNA machine is expected to be a versatile platform for other targets, such as small biomolecules and proteins. PMID: 31282008 [PubMed - as supplied by publisher]
Source: Chemistry - Category: Chemistry Authors: Tags: Chemistry Source Type: research
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