MIPs-graphene nanoplatelets-MWCNTs modified glassy carbon electrode for the determination of cardiac troponin I

An electrochemical sensor with high selectivity in addition to sensitivity was developed for the determination of cardiac troponin I (cTnl), based on the modification of cTnI imprinted polymer film on a glassy carbon electrode (GCE). The sensor was fabricated by layer-by-layer assembled graphene nano platelets (GS), multiwalled carbon nanotubes (MWCNTs), chitosan (CS), glutaraldehyde (GA) composites, which can increase the electronic transfer rate and the active surface area to capture a larger number of antigenic proteins. MWCNTs/GS based imprinted polymers (MIPs/MWCNTs/GS) were synthesized by means of methacrylic acid (MAA) as the monomer, ethylene glycol dimethacrylate (EGDMA) as the cross linker axe-azobisisobutyronitrile (AIBN) as the initiator and cTnl as the template. In comparison with conventional methods, the proposed electrochemical sensor is highly sensitive for cTnl, providing a better linear response range from 0.005 to 60 ng cm(-3) and a lower limit of detection (LOD) of 0.0008 ng cm(-3) under optimal experimental conditions. In addition, the electrochemical sensor exhibited good specificity, acceptable reproducibility and stability. Moreover, satisfactory results were obtained in real human serum samples, indicating that the developed method has the potential to find application in clinical detection of cTnI as an alternative approach. (C) 2016 Elsevier Inc. All rights reserved.