An ultrasensitive electrochemical bisphenol A sensor based on hierarchical Ce-metal-organic framework modified with cetyltrimethylammonium bromide

Abstract

This work constructed an ultrasensitive electrochemical bisphenol A (BPA) sensor using hierarchical Ce-metal-organic framework (Ce-MOF) modified with cetyltrimethylammonium bromide (CTAB) as a sensing platform. Ce-MOF had been successfully prepared and conveniently modified with a cationic surfactant (CTAB) via the electrostatic interaction. Ce-MOF and CTAB/Ce-MOF were characterized by scanning electron microscopy, X-ray diffraction, infrared spectrum, thermogravimetric analysis and zeta potentials analysis. CTAB/Ce-MOF suspension was dropped onto glassy carbon electrode (GCE) surface to fabricate CTAB/Ce-MOF/GCE. Combined with preconcentration of BPA of the long alkane chain in CTAB via hydrophobic interaction and electrocatalytic activity of Ce-MOF, the dual amplification made CTAB/Ce-MOF/GCE exhibit high electrochemical response toward the oxidation of BPA, and an electrochemical BPA sensor was constructed based on CTAB/Ce-MOF/GCE by differential pulse voltammetry. The designed BPA sensor had a wide linear range from 0.005 to 50 μmol L−1 and a low detection limit of 2.0 nmol L−1 (S/N = 3). The proposed sensor had excellent reproducibility, stability and anti-interference, and was successfully employed for BPA detection in real samples. This convenient and sensitive sensor proved to be a promising and reliable tool for detecting BPA in food and environmental pollution.