Optical Cavity Fibre Sensor for Detection of Microcystin-LR in Water

Abstract

The deterioration of water quality by Cyanobacteria causes outbreaks and epidemics associated with harmful diseases in Humans and animals because of the released toxins. Microcystin-LR (mcyst) is one of the most widely studied hepatotoxin and World Health Organization recommends a maximum value of 1 µg L-1 of mcyst in drinking-water. Therefore, there is a great demand for remote, real-time sensing techniques to detect and quantify the presence of mcyst. In this work a Fabry-Perot sensing probe based on a fibre tip coated with a mcyst sensitive thin film is presented. Highly specific recognition membranes, using sol-gel based Molecular Imprinted Polymers (MIPs), were developed to quantify microcystins in water, showing great potential in the analysis of this kind of samples. The fibre Fabry-Pérot MIP sensor shows a linear response to mcyst concentration with a sensitivity of -13.2 ± 0.4 nm L μg-1.