Controlled-Release Electrochemiluminescence Biosensor with Strong Self-On Effect by a Multiple Signal Amplification Strategy for Trace Detection of Prostate-Specific Antigen.

The enhancement of sensitivity in biological analysis detection can reduce the probability of false positives of the biosensor. In this work, a novel self-on controlled-release electrochemiluminescence (CRE) biosensor was designed by multiple signal amplification and framework-enhanced stability strategies. As a result, the changes of the ECL signal were enhanced before and after the controlled-release process, achieving sensitive detection of prostate-specific antigen (PSA). Specifically, for one thing, Fe3O4@CeO2-NH2 with two paths for enhancing the generation of coreactant radicals was used as the coreaction accelerator to boost ECL performance. For another, due to the framework stability, zeolitic imidazolate framework-8-NH2 (ZIF-8-NH2) was combined with luminol to make the ECL signal more stable. Based on these strategies, the constructed CRE biosensor showed a strong self-on effect in the presence of PSA and high sensitivity in a series of tests. The detection range and limit of detection (LOD) were 5 fg/mL to 10 ng/mL and 2.8 fg/mL (S/N = 3), respectively, providing a feasible approach for clinical detection of PSA.