The electronic conductive metal-organic frameworks (EC-MOFs) based on a single ligand are not suitable for the accurate detection of bisphenol A (BPA) due to the limitations of their electron-transfer-based sensing mechanism. To overcome this drawback, we developed EC-MOFs with novel dual-ligands, 2,3,6,7,10,11-hexahydroxy-sanya-phenyl (HHTP) and tetrahydroxy 1,4-quinone (THQ), and metal ions. A new class of 2D π-conjugation-based EC-MOFs (M-(HHTP)(THQ)) was synthesized by a self-assemble technique. Its best member (Cu-(HHTP)(THQ)) was selected and combined with reduced graphene (rGO) to form a Cu-(HHTP)(THQ)@rGO composite, which was thoroughly characterized by X-ray diffraction, field scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Cu-(HHTP)(THQ)@rGO was drop-cast onto a glassy carbon electrode (GCE) to obtain a sensor for BPA detection. Cyclic voltammetry and electrochemical impedance tests were used to evaluate the electrode performance. The oxidation current of BPA on the Cu-(HHTP)(THQ)@rGO/GCE was substantially higher than on unmodified GCE, which could be explained by a synergy between Cu-(HHTP)(THQ) (which provided sensing and adsorption) and rGO (which provided fast electron conductivity and high surface area). Cu-(HHTP)(THQ)@rGO/GCE exhibited a linear detection range for 0.05–100 μmol·L−1of BPA with 3.6 nmol·L−1(S/N = 3) detection limit. We believe that our novel electrode and BPA sensing method extends the application perspectives of EC-MOFs in the electrocatalysis and sensing fields.
The current study aimed to present a molecularly imprinted electrochemical sensing platform for bisphenol A (BPA) detection by synergistically combining conductive RGO-PANI hybrids with porous CoNi-MOF. The RGO-PANI network facilitated electron transfer efficiency, while the porosity of CoNi-MOF enhanced molecular recognition capacity through expanded surface area and tailored recognition cavities. The conditions affecting the determination of BPA were also optimized. A linear increase of the current signal was observed in the concentration range of 1–500 nM BPA. The corresponding detection limit was calculated to be 0.36 nM. Selectivity tests showed good adsorption to BPA, which was attributed to the specificity of the MIP film. Practical validation recoveries of 95.12–103.18 % (RSD<3.6 %) were achieved in milk samples, demonstrating reliability in complex matrices. This study balanced sensitivity and cost-effectiveness compared to other sensors. This sensor provided a viable method for environmental and food safety monitoring.
危险品化学品经营许可证（带存储）