New polymer passive sampler for sensitive biomonitoring of lipid-rich matrices (Letter)

Abstract

The feasibility of passive sampling biological matrices to quantify contaminants has been demonstrated using polydimethylsiloxane (PDMS). PDMS has, however, low sorptive capacity for hydrophobic compounds (with Klipid-PDMS ∼ 30-40), and increasing the sampler volume and thus the extent of chemical mass transfer is not feasible because of concomitant lipid transfer. We therefore developed new polymers by graft polymerization from PDMS substrates and evaluated the mechanism and kinetics of lipid transfer. Klipid-polymer was significantly improved to 6.7 ± 0.53 for dioxins and 0.78 ± 0.15 for PCBs using poly(tert-butyl methacrylate) (PtBuMA) chain grafts. Consistent with this, the PtBuMA solubility of selected dioxins was 6-10 times higher than that of PDMS. Lipid transfer followed a swelling process, which was rapid (t95% = 20-72 h), independent of tissue lipid content and proportional to polymer sampler volume. The new PtBuMA polymer offers new opportunities for sensitive, rapid biomonitoring of PBTs and possibly also less stable neutral hydrophobic compounds in biota and food.