Dual-function antifouling/sterilization electrically neutral hydrogel mediated bipolar autoluminescencet coreactant-free electrochemiluminescent biosensor.

The scarcity of cathodic autoluminescencet restricts the development of coreactant-free electrochemiluminescent sensor for simultaneous detection of two targets. Herein, a novel coreactant-free electrochemiluminescent sensor was prepared based on Zr-DPA@TCPP MOF and AuAgNCs bimetallic nanoclusters served as a cathodic and anodic autoluminescencet emitter respectively. Significantly, this sensor system without any coreactants, effectively overcoming the simultaneous detection issue typically relying on different coreactants for cathode and anode luminescence. Meanwhile, complex matrix components can compromise the specificity and accuracy of the detection. Therefore, highly conductive and electrically neutral hydrogel was obtained to reduce interference from non-target substances. Poly (3,4-ethylenedioxythiophene): polystyrene sulphonate (PEDOT: PSS) was encapsulated in hydrogel to obtain PEDOT: PSS@hydrogel, besides, the crosslinking agents citronellal and TCPP provide a sterilization effect. Dual-function antifouling/sterilization electrically neutral hydrogel effectively addresses the main issues of complex matrix interference and secondary contamination. Under optimal conditions, the linear range was 1 × 10-3 ∼ 1 × 105 ng/L for Cd(II) and 1 ∼ 1 × 108 CFU/mL for S. aureus. The biosensor achieves remarkably low limits of detection (LODs) at 1.71 pg/L and 1.36 CFU/mL for Cd(II) and S. aureus, respectively. This work offers a new perspective on the development of coreactant-free ECL technology with high accuracy and stability.