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.