An specific photoelectrochemical sensor based on pillar[5]arenes functionalized gold nanoparticles and bismuth oxybromide nanoflowers for bovine hemoglobin recognition

In this work, the ultrasensitive photoelectrochemical (PEC) sensor for the detection of bovine hemoglobin (BHb) was developed based on water-soluble pillar[5]arenes (WP5) functionalized gold nanoparticles (Au NPs) and bismuth oxybromide (BiOBr) nanoflowers (Au@WP5/BiOBr). The photoelectrical signal of dopamine (DA) was decreased after adding the different concentrations of BHb due to the formation of hydrogen bond between the COOH groups of BHb molecules and the NH 2 group of DA, which could achieve the indirect detection of BHb. Benefiting from the photo-generated electron-holes of BiOBr nanoflowers, the localized surface plasmon resonance (LSPR) effect of Au NPs, the host–guest interaction of WP5 between and DA, the PEC sensor showed a specifically   recognize toward BHb with a wide detection range of 1.0 × 10 −11 –1.0 × 10 −1 mg/mL and a detection limit of 4.2 × 10 −12 mg/mL (S/N = 3). Additionally, the proposed PEC sensor also displayed good stability, remarkable selectivity and provided a promising strategy of design pillar[5]arenes functionalized photoelectric activity nanomaterials for PEC sensing application.