Application of low-temperature glassy carbon films in solid-phase microextraction.

Area of Science:

• Analytical Chemistry
• Materials Science

Background:

• Solid-phase microextraction (SPME) relies on selective sorbent coatings.
• Existing commercial SPME phases have limitations in selectivity.
• Low-temperature glassy carbon (LTGC) presents unique adsorptive properties.

Purpose of the Study:

• Investigate LTGC films as a novel sorbent coating for SPME.
• Evaluate the selectivity of LTGC coatings based on molecular characteristics and processing temperature.
• Demonstrate the application of LTGC-SPME for analyzing aromatic hydrocarbons and taste/odor contaminants.

Main Methods:

• LTGC films were prepared by coating porous silica with a precursor, followed by heat curing (300-1000°C).
• LTGC-coated silica particles were immobilized onto stainless steel fibers using a sol-gel process.
• Extractions were performed using headspace and liquid SPME, followed by Gas Chromatography-Flame Ionization Detection (GC-FID) analysis.

Main Results:

• LTGC coatings exhibited selectivity based on solute molecular shape and polarizability.
• Higher processing temperatures enhanced the selective adsorption mechanism.
• Effective extraction of aromatic hydrocarbons and taste/odor compounds (geosmin, 2-methylisoborneol, 2,4,6-trichloroanisole) was demonstrated.

Conclusions:

• LTGC films are a promising selective sorbent for SPME applications.
• The selectivity is tunable via processing temperature, offering advantages over commercial phases.
• LTGC-SPME provides a viable method for analyzing complex environmental samples.