Two highly stable and selective solid phase microextraction fibers coated with crown ether functionalized ionic...

Area of Science:

• Analytical Chemistry
• Materials Science

Background:

• Solid phase microextraction (SPME) is a widely used technique for sample preparation.
• Ionic liquids (ILs) offer unique properties as stationary phases in chromatography and SPME.
• Crown ethers are known for their selective binding of cations, enhancing analyte extraction.

Purpose of the Study:

• To synthesize and characterize two novel crown ether functionalized ionic liquid (FIL)-based SPME fibers.
• To evaluate the thermal stability, chemical resistance, and selectivity of the prepared FIL-SPME fibers.
• To investigate the influence of different sol-gel preparation methods on fiber performance.

Main Methods:

• Sol-gel technology was employed to prepare FIL-SPME fibers using two synthesized FILs: [TMSP(Benzo15C5)HIM][N(SO2CF3)2] and [A(Benzo15C5)HIM][N(SO2CF3)2].
• Chemical bonding of [TMSP(Benzo15C5)HIM][N(SO2CF3)2] was achieved via hydrolysis and polycondensation.
• [A(Benzo15C5)HIM][N(SO2CF3)2] was incorporated through free radical crosslinking, forming organic-inorganic copolymer coatings.

Main Results:

• The prepared FIL-SPME fibers exhibited 'bubble-like' surface characteristics and significantly enhanced thermal stability (up to 400°C).
• The fibers demonstrated strong solvent, acid, and alkali resistance, along with good reproducibility.
• High selectivity for medium polar to polar compounds was observed, attributed to synergistic interactions of ILs and benzo-15-crown-5 functionalities.

Conclusions:

• Novel crown ether FIL-based SPME fibers were successfully prepared using sol-gel technology.
• The developed fibers offer superior thermal stability and chemical resistance compared to previous materials.
• The distinct selectivity profiles of the two fibers highlight the impact of preparation methods on the final coating composition and performance.