We report an electrodeposited poly(pyrrole-co-pyrrolepropylic acid) copolymer modified electroactive graphene-carbon nanotubes composite deposited on a glassy carbon electrode to detect the protein antigen(cTnI). The ...We report an electrodeposited poly(pyrrole-co-pyrrolepropylic acid) copolymer modified electroactive graphene-carbon nanotubes composite deposited on a glassy carbon electrode to detect the protein antigen(cTnI). The copolymer provides pendant carboxyl groups for the site-specific covalent immobilization of protein antibody, antitroponin I. The hybrid nanocomposite was used as a transducer for biointerfacial impedance sensing for cTnI detection.The results show that the hybrid exhibits a pseudo capacitive behaviour with a maximum phase angle of 49° near 1 Hz,which is due to the inhomogeneous and porous structure of the hybrid composition. The constant phase element of copolymer is 0.61(n = 0.61), whereas, it is 0.88(n = 0.88) for the hybrid composites, indicating a comparatively homogeneous microstructure after biomolecular functionalization. The transducer shows a linear change in charge transfer characteristic(R_(et)) on cTnI immunoreaction for spiked human serum in the concentration range of 1.0 pg mL^(-1)–10.0 ng mL^(-1). The sensitivity of the transducer is 167.8 ± 14.2 Ω cm^2 per decade, and it also exhibits high specificity and good reproducibility.展开更多
文摘We report an electrodeposited poly(pyrrole-co-pyrrolepropylic acid) copolymer modified electroactive graphene-carbon nanotubes composite deposited on a glassy carbon electrode to detect the protein antigen(cTnI). The copolymer provides pendant carboxyl groups for the site-specific covalent immobilization of protein antibody, antitroponin I. The hybrid nanocomposite was used as a transducer for biointerfacial impedance sensing for cTnI detection.The results show that the hybrid exhibits a pseudo capacitive behaviour with a maximum phase angle of 49° near 1 Hz,which is due to the inhomogeneous and porous structure of the hybrid composition. The constant phase element of copolymer is 0.61(n = 0.61), whereas, it is 0.88(n = 0.88) for the hybrid composites, indicating a comparatively homogeneous microstructure after biomolecular functionalization. The transducer shows a linear change in charge transfer characteristic(R_(et)) on cTnI immunoreaction for spiked human serum in the concentration range of 1.0 pg mL^(-1)–10.0 ng mL^(-1). The sensitivity of the transducer is 167.8 ± 14.2 Ω cm^2 per decade, and it also exhibits high specificity and good reproducibility.