Exploring colorimetric detection of perfluorooctane sulfonate using micelle solubilised porphyrin

Abstract

The harmful pollutant perfluorooctane sulfonate (PFOS) is difficult to detect without extensive laboratory equipment used by trained personnel. Herein, we report the use of a micelle-encapsulated porphyrin host molecule as a rapid colorimetric indicator for PFOS and its anionic salts. A range of common commercially available surfactants were tested and optimised to encapsulate the hydrophobic highly pigmented porphyrin sensor molecule. This method was used for the detection of PFOS in aqueous solutions at concentrations as low as 3 ppm. Colour space RGB information was extracted from a mobile phone photograph and parameterised, allowing for threshold PFOS detection, demonstrating the applicability of this method as an easily accessible approach to inform an untrained user.