Fabrication of Superoxide Dismutase (SOD) Imprinted Poly(ionic liquid)s via eATRP and its Application in Electrochemical Sensor

Superoxide dismutase (SOD) plays an important role in nearly all living cells. In this study, SOD imprinted poly(ionic liquid)s (SIPILs) were prepared on the surface of the bare Au electrode modified with nano-palladium and nano-gold (Au/nPd/nAu/SIPILs). SIPILs was synthesized with 1-vinyl-3-propyl imidazole sulfonate ionic liquids as functional monomers via electrochemically mediated atom transfer radical polymerization (eATRP) catalyzed by SOD. The Au/nPd/nAu/SIPILs was examined by cyclic voltammetry (CV), scanning electron microscope (SEM), energy-dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS). The Au/nPd/nAu/SIPILs was also used as an electrochemical sensor to determine SOD by differential pulse voltammetry (DPV). Under the optimal conditions, the detection range of SOD was from 1.0×10 −8 to 1.0×10 2 mg L −1 with a limit of detection of 8.90×10 −9 mg L −1 (S/N=3). Compared with other methods, the sensor based on SIPILs had the broader linear range and lower detection limit.