Enzymatic recognition of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) in human plasma samples using <scp>HRP</scp> immobilized on the surface of poly(arginine‐toluidine blue)‐ <scp>Fe<sub>3</sub>O<sub>4</sub></scp> nanoparticles modified polydopamine; A novel biosensor
Sanam Sardaremelli, Mohammad Hasanzadeh, Farzad Seidi
Abstract
Abstract In this study, an innovative strategy was proposed for the electrocatalytical reduction and enzymatic biosensing of hydrogen peroxide (H 2 O 2 ) using chronoamperometry technique. For the first time, immobilization of horseradish peroxidase (HRP) in polydopamine‐modified magnetic nanoparticles (PDA‐MNPs) was successfully performed. Also, poly( l ‐arginine/toluidine blue) film–modified glassy carbon electrode was constructed through co‐electropolymerization of l ‐arginine and toluidine blue on the surface of GCE using cyclic voltammetry technique. The engineered hybrid thin film provides strong functionalities for efficient grafting of PDA‐MNPs which, in turn, enable the covalent immobilization of HRP. The proposed biosensor was used for the detection of H 2 O 2 in the range of 0.5‐30 μM with a low limit of quantification 0.23 μM. It also was successfully applied for the investigation of hydrogen peroxide in human plasma samples.