Abstract
PhD. (Chemistry)
This thesis focuses on functionalising the silicone membrane by filling it with synthesised γ-Fe2O3 nanoparticles for the purpose of using it as a passive sampling device for monitoring microcystins and cylindrospermopsin in aquatic environments. The identity and purity of the synthesised nanoparticles was verified by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), surface zeta potential analyser and Brunauer-Emmet-Teller (BET). There was no chemical uptake of microcystin compounds into the silicone membrane without a suspension of maghemite nanoparticles. But, a linear uptake of microcystin compounds was observed into the functionalised silicone membrane passive sampler throughout the exposure period. These findings suggest that the silicone membrane filled with a suspension of synthesised γ-Fe2O3 nanoparticles can be an efficient, green and less costly instrument useful in estimating biotoxin concentrations in South African waters and the world at large.