Entropy-driven catalytic amplification adjusted by stoichiometry for single-nucleotide variants detection with high abundance sensitivity.

Single-nucleotide variants (SNV) detection with high abundance sensitivity is of great significance in clinical application, molecular diagnostics and biological research. In this study, a high abundance sensitivity SNV detection strategy based on entropy-driven catalytic (EDC) amplification adjusted by stoichiometry is proposed. In EDC, the toehold exchange reaction is used to initiate subsequent catalytic reaction and can be adjusted by stoichiometry. When the by-product concentration in the toehold exchange reaction is excessive, the forward reaction will be inhibited, which can reduce or even block the unexpected reaction between the non-target and the probe. Meanwhile, some targets can still successfully take a toehold exchange reaction with the probe, thus completing the subsequent EDC. By adjusting the EDC, the SNV identification specificity of this system was improved and is superior to any single adjusted stoichiometry or EDC. When the low abundance target is detected from the mixture, this strategy enables SNV detection at 0.1% abundance with high abundance sensitivity. And even if the mixture contains three kind of 1000-fold interference sequences, this strategy can still discriminate the target SNV. Furthermore, the practical applicability of the adjusted EDC system was verified by p53 mutation discrimination in human urine. Image 1 • A SNV detection strategy based on EDC adjusted by stoichiometry is proposed. • EDC adjusted by stoichiometry improves specificity of the SNV detection system. • This strategy can detect SNV at 0.1% abundance with high abundance sensitivity. • Targets can be identified from a mixture containing three 1000-fold interference. • P53 mutation in human urine can be detected by this strategy. [ABSTRACT FROM AUTHOR]