Nanostructured hybrid monolith with integrated stirring for the extraction of UV-filters from water and urine samples.

This article presents a monolithic extraction unit with integrated stirring using carbon nanohorns and methacrylate-based compounds as monomers. The hybrid monolithic material was prepared by thermal polymerization at 70 °C for 24 h, and was applied for the extraction of UV-filters from waters and human urine samples. To achieve the integrated stirring unit, the monolith was grown over an ironware. Variables dealing with the polymerization mixture composition and the microextraction procedure were studied in depth. The resulting hybrid monolithic polymer was also characterized by scanning electron microscopy (SEM) and nitrogen intrusion porosimetry. The target analytes were quantified by UPLC-DAD, and the limits of detection were between 1 and 10 μg/L. The precision of the method (inter extraction units) expressed as relative standard deviation ranged from 5.4% and 7.9%. Also, relative recoveries values of the analyte spiked to swimming pool water and urine samples varied in the interval 72-124 and 71-114%, respectively.