A comprehensive review on synthesis and applications of cryogel-based sorbents in solid-phase extraction techniques

Cryogels are three-dimensional porous materials created by polymerizing water-soluble monomers and crosslinkers at sub-zero temperatures. Cryogel-based sorbents, with their distinct physical and chemical characteristics such as superporosity, elasticity, water permeability, and ease of chemical modification, hold promise in revolutionizing sample preparation across diverse applications. This review aims to offer a comprehensive overview of the materials used and synthesis methods, encompassing free radical polymerization, irradiation polymerization, condensation polymerization, and self-assembly gel formation. Moreover, it covers characterization methods such as Fourier-transform infrared spectroscopy, Scanning electron microscopy, nitrogen porosimetry, swelling and mechanical properties. Furthermore, the review highlights the advantages of cryogels over other conventional sorbents, emphasizing their remarkable extraction efficiency and selectivity when applied to various real samples, including foods, environmental and biological samples. The review also delves into recent advancements in the utilization of cryogels as sorbents in diverse solid-based extraction procedures, addressing current obstacles in this research domain and offering insights into future prospects.