Rolling-Circle-Amplification-Assisted DNA Biosensors for Sensitive and Specific Detection of Hypochlorous Acid and Myeloperoxidase

Hypochlorous acid (HClO) is a common reactive oxygen species (ROS), with high chemical reactivity. Myeloperoxidase (MPO) an enzyme that catalyzes in vivo redox reactions between H2O2 and Cl− to produce HClO. Abnormal levels of HClO MPO may lead oxidative stress, irreversible tissue damage and, thus, serious diseases; they are thus becoming important biomarkers therapeutic targets. In this work, using HClO-induced site-specific cleavage phosphorothioate-modified DNA trigger rolling circle amplification (RCA), RCA-assisted biosensors have been developed for the highly sensitive specific detection MPO. Only two oligonucleotides used sensing systems. The powerful signal-amplification capability RCA endows systems sensitivity, fluorescent response thioflavin T (ThT) G-quadruplexes products makes label-free signal output possible. proposed were demonstrated work well not only quantitation limits 1.67 nM 0.33 ng/mL, respectively, but also screening inhibitory capacity evaluation inhibitors, holding great promise disease diagnosis drug analysis.