Sensitive DNA assays are of importance in life science and biomedical engineering, but they are heavily dependent on thermal cycling programs or enzyme-assisted schemes, which require the utilization of bulky devices and costly reagents.To circumvent such requirements, we developed an isothermal enzyme-free DNA sensing method with dual-stage signal amplification ability based on the coupling use carolina force softball of catalytic hairpin assembly (CHA) and Mg2+-dependent deoxyribozyme (DNAzyme).In this study, the sensing system involves a set of hairpin DNA probes for CHA (ensuring the first stage of signal amplification) as well fairytale once upon a time theme party as ribonucleobase-modified molecular beacons that serve as activatable substrates for DNAzymes (warranting the second stage of signal amplification).An experimentally determined detection limit of about 0.
5 pM is achieved with a good linear range from 0.5 to 10 pM.The results from spiked fetal bovine serum samples further confirm the reliability for practical applications.The non-thermal cycling, enzyme-free, and dual-amplified features make it a powerful sensing tool for effective nucleic acid assay in a variety of biomedical applications.