Surface metallization of human hair via electroless copper-plating for self- supported nonenzymatic glucose sensor

Surface engineering of human hair was successfully used as a self-supported electrochemical sensor to detect glucose in human serum. Polydopamine (PDA) was firstly grafted on hair by oxidative self-polymerization of dopamine and then the copper nanoparticles (CuNPs) were electrolessly deposited to achieve surface metallization of hair (hair@CuNPs). The hair@CuNPs composites with uniformly dispersed conductive layer in 8 µm thickness exhibited outstanding electrocatalytic activity towards glucose oxidation. Under optimal conditions, the amperometric response of glucose on hair@CuNPs composites as self-supported nonenzymatic glucose sensor covered two linear ranges of 0.002–5 mM and 5–35 mM, respectively, and the detection limit was 1.62 µM. The proposed method provides an easy and inexpensive way to fabricate hair@CuNPs biosensor for detecting glucose level in human serum samples, indicating that hair@CuNPs composites have promising practical applications in biological analysis.