Highly sensitive and stabilized sensing of 6-benzylaminopurine based on NiCo2O4 nanosuperstructures

Abstract

NiCo₂O₄ nanosuperstructures that were synthesized by a facile hydrothermal method were developed for the determination of 6-benzylaminopurine (6-BAP). As a novel electric material, NiCo₂O₄ can be utilized to structure an ultrasensitive and prominently stable electrochemical sensor. The electrochemical investigation confirmed that NiCo₂O₄ nanosuperstructures stabilized via polyethyleneimine (PEI) could remarkably boost the electrocatalytic activity for the oxidation response of 6-BAP owing to its unique properties of large pore volume, good electrical conductivity and metal catalysis. The detailed electrochemical behavior of 6-BAP at PEI-NiCo₂O₄/GCE exhibited a higher peak current and more negative oxidation potential than the bare glassy carbon electrode (GCE). Simultaneously, its kinetic and thermodynamic parameters were further calculated, indicating that this sensing platform accomplished excellent electrochemical catalysis towards 6-BAP. The fabricated sensor of PEI-NiCo₂O₄/GCE for 6-BAP presented a wide linear range from 10⁻¹⁰ to 10⁻⁵ M with a low detection limit of 0.1 nM. The modified electrode exhibited long-term stability and high sensitivity and showed good practicability for determining contamination in food and even broader applications.