A novel nano multi MIP sensor for simultaneous detection of cTnT & HbA1c

A nano-molecularly imprinted polymer (N-MIP) dual-sensor based on a graphene screen-printed electrode was developed for the detection of glycated hemoglobin and cardiac troponin T (cTnT), separately. In order to obtain a biomimetic surface, a conductive co-polymer matrix was deposited on the surface of graphene oxide (GO) electrode. The sensor probe was modified via electropolymerization of aniline and carboxylated aniline on the graphene oxide (GO) electrode, in the presence template proteins (cTnT for cardiac troponin T probe and HbA1c for glycated hemoglobin probe) by cyclic voltammetry. The surfaces of both sensors were characterized using cyclic and differential pulse voltammetry (CV), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), quartz crystal microbalance (QCM). The best biomimetic surface nanotexture was obtained at aniline/carboxylatedaniline ratio of 1:4. The linear ranges of cTnT and HbA1c were from 0.02 to 0.09 ng/mL and from 0.004 to 0.81 μg/mL, with detection limits of 0.008 ng/mL and 4.3 ng/mL, respectively. The reliability of the M-NIP cTnT and HbA1c sensors was examined by comparing the results with those obtained from HPLC method and It was observed that the results from N-MIP sensors and HPLC had a great correlation.