Sensitive detection of organic pollutants in water using self-assembled monolayers of p-tert-butylcalix[4]arenetetrathiol on a quartz crystal microbalance

This paper discusses a novel approach to chemical sensing of trace organics in aqueous, liquid media utilizing a self-assembled monolayer of p-tert-butylcalix[4]arenetetrathiol (BCAT) on a quartz crystal microbalance (QCM). Replacement of the phenol functionalities of p-tert-butyl-calix[4]arene with thiols enables the self assembly of these basket-shaped, complexing agents onto a mercury-coated QCM. The results demonstrate that the BCAT cage exhibits reversible, shape- or size-selective adsorption of various organic pollutants at the low ppm level in water.