A Fluorometric Fullerenol Sensor for Rapid Detection of Ionic and Non-Ionic Surfactants

Abstract

Abstract A fullerenol sensor utilizing fluorescence quenching of a labeled protein was developed for rapid detection and quantification of ionic (cetyltriammonium bromide (CTAB), sodium dodecyl sulphate, (SDS)) and non-ionic (Tween 20 and Triton X-100) surfactants in solution. The sensor is based on the competitive adsorption of the surfactants and the fluorescently labeled protein to fullerenols – hydroxylated buckminsterfullerenes. The fluorescence quenching between fullerenols and the fluorochrome-labeled protein was detected and related to the replacement of the labeled protein by the surfactants. The non-ionic surfactants could be measured at sub to low micromolar concentrations whereas significantly higher concentration of ionic surfactants was required to efficiently cover the fullerenol surface. The combination of the novel fullerenol sensor with existing micro titer plate fluorometric instrumentation can find use as a versatile and rapid probe for tracing various types of surface active molecules.