Development of a novel macroporous passive sampler with integrated solid phase extraction for cost-effective water...

Passive samplers, for instance Chemcatcher, Microporous Polyethylene Tube passive samplers (MPTs) and Diffusive Gradients in Thin Films (DGT), are widely used for monitoring time-weighted average concentrations (C_TWA) of contaminants in waters. This study presents ChemTRAP, a novel passive sampler using two macroporous filters (MFs) as both sorbent support and diffusion matrix for analyte uptake. This design enables analyte recovery by solid-phase extraction (SPE), thereby reducing per-unit costs and simplifying workflows. Six organic analytes and six heavy metals were used to evaluate ChemTRAPs embedded with Hydrophilic-Lipophilic Balanced resin or Chelex100 resin. The ChemTRAP, as an SPE device, achieved a mean recovery of 94.3% for all 12 analytes in both simulated and Lake Nanhu water. The performance of Chelex100 resin remained stable over 10 reuse cycles. In a preliminary field test, ChemTRAPs showed an average sampling rate of 2.4 mL/d, comparable to MPTs and DGTs. The average recovery of 12 analytes was 73.4% (95% Confidence Interval: 54-92%), indicating that ChemTRAP-derived C_TWA are representative of ambient concentrations, despite a slight negative bias likely attributable to biofouling. While further field validation is necessary, investigation of analyte diffusion in MFs is also desirable to develop a predictive R_S model comparable to that established for DGTs.