Supramolecular interaction of 2,4-dichlorophenol and β-cyclodextrin functionalized ionic liquid and its preliminary study in sensor application

The supramolecular interaction of 2,4-dichlorophenol (2,4-DCP) and β-cyclodextrin functionalized ionic liquid, a mono-6-deoxy-6-(3-benzylimidazolium)-β-cyclodextrin tosylate (β-CD-BIMOTs) has been investigated. The inclusion complex of β-CD-BIMOTs-2,4-DCP complex was analyzed with conventional spectroscopic techniques and compared with native β-CD-2,4-DCP complex. The mechanism of the inclusion too was studied and discussed based on FTIR, 1H NMR and 2D NOESY analysis. β-CD-BIMOTs has a stronger binding affinity towards 2,4-DCP compared to native β-CD based on the formation constant value calculated. In this work, modified electrodes were fabricated by mixing β-CD-BIMOTs and carbon paste electrode (CPE) for determination of 2,4-DCP. The electrochemical behavior of 2,4-DCP at β-CD-BIMOTs/CPE exhibits higher electrochemical performance than that of native β-CD/CPE and CPE, revealing that CPE modified β-CD-BIMOTs not only displays good electrical properties of the ionic liquid but also exhibits high supramolecular recognition properties of β-CD-BIMOTs through the formation of an inclusion complex between β-CD-BIMOTs and 2,4-DCP molecules. This preliminarily study shows that β-CD-BIMOTs can act as an inexpensive electrochemical sensor that is suitable for the determination of 2,4-DCP.