Magnetic paper-based sorptive phase for enhanced mass transference in stir membrane environmental samplers

In this article, a magnetic paper-based sorptive phase is synthesized, which synergically combines the sorption capacity of a polyamide with the magnetic behavior of silica shielded Fe₃O₄ nanoparticles. The resulting material can be easily integrated into a drill-based environmental sampler, minimizing the diffusion boundary layer for enhanced mass transference. The new material has been evaluated for the extraction of four parabens and triclosan from swimming pool water samples. The main variables affecting the extraction have been studied in detail. The sampler is easy to transport allowing the on-site extraction of the analytes. This aspect can simplify the overall analytical procedure as only the sorptive phases, and not the samples, must be transported to the lab for the final analysis. The combination of the sampler with liquid chromatography-mass spectrometry allows determining the target analytes with limits of detection between 0.07 μg/L (butylparaben) and 0.1 μg/L (methylparaben and propylparaben). The precision, calculated at 5 μg/L, provides relative standard deviations better than 8%. The accuracy, which was evaluated spiking a blank swimming pool water sample with the target analytes at a concentration of 0.75 μg/L, provided relative recoveries in the range from 88 to 98%.