Preparation of hemoglobin (Hb) imprinted polymers with CO2 response and its biosensing application

A novel hemoglobin (Hb) imprinted polymers with CO 2 response (CHIPs) were prepared on the surface of Au electrode modified by zinc oxide (CHIPs/ZnO/Au) via electrochemically mediated atom transfer radical polymerization (eATRP). The imprinted polymers were synthesized with Hb both as catalyst and template, and N,N-diethylaminoethyl methacrylate (DEAEMA) as CO 2 -responsive functional monomer. The obtained CHIPs/ZnO/Au electrode was characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and electrochemical methods. The results showed that CHIPs/ZnO/Au electrode could give higher affinity for the target protein inside a CO 2 -treated aqueous medium compared to that under N 2 -treated conditions, which make it a good electrochemical biosensor in the presence of CO 2 . The biosensor could be successfully applied for the determination of Hb by differential pulse voltammetry (DPV) measurement. The linear response range of CHIPs/ZnO/Au for detecting Hb was 1.0×10 −12 ~1.0×10 −1 mg L −1 and the detection limit was 2.1×10 −13 mg L −1 ( S / N =3). Briefly, the work in this study introduced an easy and non-toxic method for Hb determination under specific conditions and also provided a progressive approach for designing protein imprinted polymers.