Self-assembled ZnO quantum dot bioconjugates for direct electrochemical determination of allergen

We report a direct biosensor for the detection of allergy chicken ovomucoid (CHOM) based on ZnO quantum dots (QDs) and a CHOM bioconjugate. The CHOM was self-assembled onto ZnO QDs through electrostatic interaction between positively charged QDs surface and negatively charged protein. Concanavalin A was employed as a recognition element for ZnO QDs labeled CHOM. The extent detection was accomplished by square wave voltammetric (SWV) of captured QDs. The biosensor shows concentration-dependent SWV development by capturing CHOM-functionalized ZnO QDs on concanavalin A-coated chips and has a detection limit of 1 ng/mL. The proposed method makes the CHOM/ZnO QDs bioconjugate a promising biosensor for the detection of CHOM.