Functionalized β-cyclodextrin MOF with carbon nanotube conductive veins for highly sensitive and wide-concentration-range bisphenol A sensing

Bisphenol A (BPA), as an endocrine disruptive compound of public concern, is widely present in natural water and wastewater. The development of BPA detection technology is of great significance. However, the insoluble organic nature of BPA hinders its adsorption and electron transfer at hydrophilic sensing interfaces, limiting the improvement of electrochemical sensing performance. Based on the high affinity and selectivity of β -cyclodextrin ( β -CD) toward BPA, a composite material (CNT@CD-MOF) of β -cyclodextrin metal–organic framework (CD-MOF) embedded with carbon nanotubes (CNTs) was prepared in this article for electrochemical sensing of BPA. Compared with β -CD, the three-dimensional ordered structure of CD-MOF promoted the adsorption and enrichment of BPA. The doping of CNTs led to the growth of smaller sized CD-MOF, improved the material’s charge transfer ability, and enhanced its stability. Under the synergistic effect of CNTs and CD-MOF, the CNT@CD-MOF modified glassy carbon electrode exhibited a catalytic effect on BPA oxidation and significantly improved response signals, achieving detection of BPA in a fairly wide linear range of 1 nM ∼ 500 μM with a low detection limit of 0.5 nM. This study successfully applied functionalized CD-MOF for the electrochemical detection of BPA for the first time, greatly improving the electrochemical sensing performance of BPA and promoting the application of electrochemical sensing technology in BPA detection. In addition, the excellent properties of CNT@CD-MOF make it of great application value in the fields of BPA adsorption and removal.