Characterization of large surface area polymer monoliths and their utility for rapid, selective solid phase...

Area of Science:

• Polymer Chemistry
• Analytical Chemistry
• Materials Science

Background:

• Polymer monoliths are utilized in solid phase extraction (SPE) but lack comprehensive characterization linking physical properties to performance.
• Understanding the relationship between monolith structure and SPE efficiency is crucial for optimizing analytical methods.

Purpose of the Study:

• To investigate two methods for fabricating large surface area polymer monoliths with bimodal pore structures.
• To characterize these monoliths and compare their performance in SPE using probe analytes.

Main Methods:

• Fabrication of polymer monoliths using high poly(divinyl benzene) (PDVB) content and hypercrosslinking.
• Adsorption studies using frontal analysis with anisole, benzoic acid, cinnamic acid, ibuprofen, and cortisone.
• Comparison of SPE performance with particulate adsorbents and assessment of analyte recovery at different flow rates.

Main Results:

• PDVB monoliths exhibited higher adsorption capacity (298 mg/g) for anisole compared to hypercrosslinked monoliths (164 mg/g).
• BET surface area analysis revealed significant microporosity in hypercrosslinked materials (817 m²/g), while PDVB showed a similar surface area in both solvated and BET states (531 m²/g).
• PDVB monoliths demonstrated consistent anisole recovery (90%±0.103) across varying flow rates and selective permeation for efficient saccharin purification from urine.

Conclusions:

• PDVB monoliths offer superior adsorption capacity and robust performance for SPE applications.
• The bimodal pore structure of PDVB contributes to selective analyte permeation and efficient purification.
• Comprehensive characterization is essential for understanding and optimizing polymer monoliths in SPE.