Original signal amplification assay for N-Terminal pro-brain natriuretic peptide detection based on BiMoO photosensitive matrix.

An original dual signal amplification immunoassay for N-Terminal pro-brain natriuretic peptide (NT-proBNP) detection is developed based on Au NPs and Zn doped CdS nanoparticles (ZnCdS) co-sensitized BiMoO nanosheet photoelectrochemical (PEC) platform, the target is a good myocardial marker for diagnosing heart failure (HF). BiMoO as an outstanding photocatalysis material is successfully used in PEC analysis in this work, and the nanosheet structure provide a preponderance to capture superior ZnCdS in order to achieve anticipant PEC response. The doping of Zn makes the energy band of CdS matched more compatible with BiMoO, and improves the narrow band gap of CdS, making the surface plasma resonance (SPR) effect of Au NPs more significant, thus further improving the PEC response, as well as elevated the detection sensitivity of biological targets. The constructed PEC platform for NT-proBNP provides a wide detection range of 0.0001-1000 ng mL and gives the minimum detection value of 0.037 pg mL. Great stability, high selectivity, and good reproducibility are also achieved. The proposed PEC immunoassay provides more possibilities for other protein ultra-sensitivity detection.