Highly efficient photocathodic cascade material for constructing sensitive photoelectrochemical biosensor

Photocathodic biosensor possesses excellent anti-interference capability in bioanalysis, which however suffers from high electron-hole recombination rate with low photocurrent. Herein, a high-performance inorganic organic P3HT@C60@ZnO nanosphere with cascade energy band arrangement was synthesized as photoactive signal probe, which inherited the advantages of inorganic strong optical absorptivity and organic high mobility for photo-generated holes. Specifically, the well-matched band gap endowed not only the improved life for light generated carrier and promoted separation of electron-hole pairs, but also the expansion of charge-depletion layer, significantly improving the photoelectric conversion efficiency for acquiring an extremely high photo -cathodic signal that increased by 30 times compared with individual materials. Accordingly, by integrating with the efficient amplification of DNA nanonet derived from clamped hybrid chain reaction (C-HCR), a sensitive P3HT@C60@ZnO nanosphere based photocathodic biosensor was proposed for accurate detection of p53. The experimental results showed that the biosensor had a wide detection range from 0.1 fM to 10 nM and a low detection limit of 0.37 fM toward p53, offering a new avenue to construct sensitive PEC platform with superior anti-interference ability and hold a prospective application in early disease diagnosis and biological analysis.

Automated summary

In this study, a high-performance inorganic organic nanosphere with cascade energy band arrangement was synthesized for sensitive photocathodic biosensing. The biosensor showed a wide detection range and low detection limit for p53, demonstrating its potential in early disease diagnosis and biological analysis.