Silica Monolith Nested in Sponge (SiMNS): A Composite Monolith as a New Solid Phase Extraction Material for...

Area of Science:

• Materials Science
• Analytical Chemistry
• Environmental Science

Background:

• Developing novel materials for trace analysis of environmental contaminants is crucial.
• Existing solid phase extraction (SPE) materials often lack mechanical flexibility and require frits.

Purpose of the Study:

• To report a new composite silica monolith nested in sponge (SiMNS) material.
• To demonstrate its application in the trace analysis of environmental contaminants in water.
• To functionalize SiMNS for selective and efficient contaminant extraction.

Main Methods:

• SiMNS preparation via sponge absorption of hydrolyzed siloxanes and in situ gelation.
• Scanning electron microscopy (SEM) for structural analysis.
• Fabrication of SPE cartridges using functionalized SiMNS-SO3Na.
• High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for dipeptide analysis.

Main Results:

• SiMNS exhibits a mutually nested structure, enhancing mechanical flexibility and enabling fritless SPE cartridge production.
• SiMNS-SO3Na SPE cartridges show high extraction capacity and stability across a wide pH range (2-11).
• Improved method detection limits (MDLs) of 0.02-1.3 ng/L and method quantification limits (MQLs) of 0.05-4.3 ng/L were achieved for six dipeptides.
• Successful identification and quantification of Tyr-Gly, Phe-Gly, and Tyr-Ala in raw water samples.

Conclusions:

• SiMNS is a versatile and mechanically flexible material for SPE applications.
• Functionalized SiMNS-SO3Na enables efficient enrichment and trace analysis of dipeptides in environmental water.
• This work opens avenues for developing tailored SiMNS materials for diverse environmental and exposomic analyses.