MNPs@Captisol® assemblies for magnetic water remediation.

One of the increasingly valuable natural resources is clean water. As an example, intensive farming plays the dual role of an avid consumer and a potential polluter. In this regard, agrochemicals are considered emerging water pollutants that might be harmful to the environment and public health. Here we propose a new tool for water purification based on sulfobutylether-β-cyclodextrin (Captisol®) and magnetic nanoparticles (MNPs) supramolecular assemblies (MNP@Captisol®). The nano/microstructured morphology and cyclodextrin (CD) functionalization ensure respectively large surface-to-volume ratio and selectivity and sensitivity towards agrochemicals capturing 1. Once the inclusion complex between CD and the pollutant is formed, it is removed from aqueous solution by simply magnetic settling. The novel assembly based on trade Fe (II/III) oxides nanoparticles covered by Captisol® was prepared under Argon bubbling and vortex mixing, purified by magnetic settling, and characterized by DLS, TGA, XPS, TEM analyses and magnetization measurements. The MNPs@Captisol® assembly showed interesting preliminary results toward Paraquat water remediation. Due to its widespread use in agricultural and non-agricultural settings and its toxicity to humans and wildlife, the herbicide was selected as pollutant model in our studies.