A flexible capacity-metric creatinine sensor based on polygon-shape polyvinylpyrrolidone/CuO and Fe2O3 NRDs electrodeposited on three-dimensional TiO2–V2O5–Polypyrrole nanocomposite
Hamid Dehghan-Manshadi, Mohammad Mazloum‐Ardakani, Sayed Ahmad Mozaffari
Abstract
The innovations of the present work include these items; (i) Design and preparation of three-dimensional flexible conductive polymeric nanocomposites (3D-FCPNCs) containing polypyrrole (PPy), V 2 O 5 and TiO 2 and modification of their surface with polygon-shape polyvinylpyrrolidone/CuO nanorods (PVP/CuO NRDs) and Fe 2 O 3 NRDs using an hierarchical process based on isoelectric point (IEP), (ii) Application of the prepared surfaces as the flexible enzymeless creatinine sensors using four calibration curves (impedimetric, real capacitance (C ′ ), imaginary capacitance (C ″ ) and double layer capacitance (C dl )) obtained from electrochemical impedance spectroscopy (EIS) technique. The best results have been obtained using PVP/CuO NRDs–Fe 2 O 3 NRDs/TiO 2 –V 2 O 5 –PPy 3D-FCPNC hierarchical electrode with a wide range of the linear concentration range (10 nmol L −1 −1.3 mmol L −1 ). Although, determination of creatinine through extraction of parameters such as charge transfer resistance (R ct ) and C dl from measuring impedance at a wide range of frequencies provides useful information about the characteristics of the electrolyte/electrode interface, but measuring real and imaginary capacitances at a specific frequency instead of a wide frequency range can decrease the response time to lower than 1 min. Finally, the prepared hierarchical enzymeless sensors have been successfully used to estimate creatinine concentration in blood serum.