Multi-Path High Electrochemiluminescence Activation Induced by SnO2/g-C3N4 Heterojunction for Ultrasensitive Bioanalysis Using SDA-Mediated Reticular DNA Structure as Signal Amplifier

. Then, a simple and efficient SDA reaction was employed to construct a reticular 3D DNA structure for signal amplification. This 3D DNA structure functioned as an ideal molecular scaffold with high loading capacity, and excellent structural stability could provide abundant Nb.BbvCI restriction enzyme cleavage sites, enabling the effective release of a large amount of dual-output DNA, significantly improving signal amplification efficiency and detection accuracy. Finally, the proposed biosensor exhibited excellent detection performance, achieving a sensitive detection limit for miRNA-222 as low as 41.3 aM.