Effect of crosslinker/porogen ratio on sponge-nested polymer monoliths for solid-phase extraction

Area of Science:

• Analytical Chemistry
• Materials Science
• Polymer Chemistry

Background:

• Limited options exist for free-standing polymer monoliths in analytical sample preparation, particularly for solid-phase extraction (SPE).
• Melamine-formaldehyde sponges offer a flexible support for creating diverse shapes of polymer monoliths.

Purpose of the Study:

• To evaluate the crosslinker/porogen ratio for highly porous sponge-nested divinylbenzene (DVB) polymer monoliths.
• To develop and optimize a method for the solid-phase extraction of bisphenols using these novel monoliths.

Main Methods:

• Preparation of divinylbenzene (DVB) polymer monoliths nested within melamine-formaldehyde sponges.
• Optimization of the crosslinker/porogen ratio to enhance monolith porosity and extraction efficiency.
• Application of the developed monoliths for the solid-phase extraction of bisphenol F, bisphenol A, bisphenol AF, and bisphenol B.

Main Results:

• Monoliths composed of 50 wt % DVB and 50 wt % porogens demonstrated the highest recovery rates for bisphenols.
• The optimized method exhibited a linear range from 2.5 µg L⁻¹ to 150 µg L⁻¹ for BPA and BPAF, and 5 µg L⁻¹ to 150 µg L⁻¹ for BPB and BPF.
• Limits of detection (LOD) ranged from 0.36 µg L⁻¹ to 1.09 µg L⁻¹, and limits of quantification (LOQ) ranged from 1.20 µg L⁻¹ to 3.65 µg L⁻¹.
• Recoveries for spiked bisphenols in tap water and polycarbonate container water samples were between 82% and 114%.

Conclusions:

• Sponge-nested DVB polymer monoliths are effective for the solid-phase extraction of bisphenols.
• The optimized monoliths provide sensitive and efficient extraction of target bisphenols from aqueous samples.
• This approach offers a promising solution for analytical sample preparation, particularly for environmental and food safety analysis.