Journal of Analytical Science and Technology (Jun 2023)
A novel cysteine catalytic oxidation-based colorimetric approach for sensitive analysis of acute pancreatitis-related microRNA
Abstract
Abstract It is essential to establish simple, sensitive and accurate quantitative approaches for microRNAs (miRNAs) identification due to its crucial roles in a variety of physiological and pathological processes. Herein, we propose a novel RCA-based colorimetric method for sensitive and reliable miRNA analysis. In this approach, cyclization of the padlock sequence by miRNA-21 initiates the RCA to produce numerous G-rich sequences. The generated G-rich sequences fold to G-quadruplex DNAzyme that is capable of catalyzing cysteine to cystine which could mediate the gold nanoparticle-based color reaction, outputting results that can be observed directly by naked eyes. Based on this, the approach exhibits a wide detection range with a low limit of detection of 4 fM. In addition, the dual target recognition endows the method a greatly improved selectivity.
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