Enzyme Mimic Behavior of Platinum(II) Complex with Tridentate Ligand—Fe3O4—MWCNT Nanocomposite for the Electrochemical Detection of H2O2 and NADH
摘要
A platinum-based complex molecule, [PtLCl]Cl (Pt-L), featuring a tridentate ligand (L = 2,6-bis(benzimidazol-2-yl)-4-hydroxypyridine) was synthesized. Subsequently, Pt-L was successfully bonded to amine-terminated Fe3O4NP, and MWCNTs were incorporated into the modified Fe3O4 surface. The resulting electrode was shown to possess outstanding electrocatalytic activity for detecting H2O2 and NADH, characterized by enhanced cathodic or anodic peak responses and favorable shifts in the reduction or oxidation peak potentials for both analytes. The sensing platform demonstrated excellent electrochemical performance in non-enzymatic measurements of H2O2 and NADH, achieving notably low detection limits of 0.017 µmol L−1 for H2O2 and 0.113 µmol L−1 for NADH. These findings were acquired within the concentration range of 10 to 500 µmol L−1, indicating the linear portion of the calibration graphs obtained in the concentration ranges of 10 to 5000 µmol L−1 for H₂O₂ and 10 to 25,000 µmol L−1 for NADH, which exhibited exponential behavior for both analytes. The developed sensor displayed high responsiveness, long-lasting stability, and requisite interference, rendering it suitable for routine detection of H2O2 and NADH in biological specimens.
Graphical Abstract