Desenvolvimento de sorvente monolítico polimérico impresso molecularmente para extração em ponteira descartável de BDE-209

Abstract

Flame retardants are chemical substances used to reduce the flammability of materials and are widely applied in sectors such as construction, automotive, electronics, and textiles to enhance fire safety. However, traditional halogenated flame retardants pose environmental and health risks due to the release of toxic compounds. Disposable pipette tip extraction (DPX) has emerged as a promising sample preparation technique, offering speed, reduced solvent consumption, and high extraction efficiency. Nevertheless, commercially available particulate sorbents have limitations such as low selectivity and reproducibility, and require filters, increasing device costs. Monolithic sorbents, prepared directly inside the pipette tip, eliminate this need and offer advantages including good permeability, mechanical stability, and functionalization via molecular imprinting (MIP), which enhances sorbent selectivity. This study aimed to develop a hydrophobic, hierarchically porous monolithic polymer sorbent for pipette tip application, based on the polymerization of trimethylolpropane triacrylate (TMPTA) and ethylene glycol dimethacrylate (EDMA), molecularly imprinted with decabromodiphenyl ether (BDE-209). The monolith preparation was optimized using a central composite design with two variables: polymerization time and temperature. The materials were characterized by water permeability (~5 mL min⁻¹), scanning electron microscopy, infrared spectroscopy, and thermogravimetric analysis, confirming a homogeneous, highly porous, and thermally stable structure up to ~325 °C. The poly(TMPTA-co-EDMA) monoliths exhibited a specific surface area of ~250 m² g⁻¹. Extraction performance evaluation showed that the MIP monoliths achieved approximately 1.7 times greater BDE-209 extraction compared to NIP. Thus, DPX with molecularly imprinted polymeric monolithic sorbents for BDE-209 proved to be a viable and selective approach for efficient flame retardant extraction.