Development of fluorinated low temperature glassy carbon films for solid-phase microextraction

Area of Science:

• Analytical Chemistry
• Materials Science
• Separation Science

Background:

• Solid-phase microextraction (SPME) is a widely used technique for sample preparation.
• Development of novel SPME fiber coatings is crucial for improving extraction selectivity and efficiency.
• Fluorinated materials offer unique properties for selective chemical interactions.

Purpose of the Study:

• To synthesize and characterize novel SPME fibers based on supported fluorinated glassy carbon.
• To evaluate the selectivity of these new fibers for extracting monohalogenated benzenes from aqueous solutions.
• To compare the performance of the novel fibers with commercially available SPME materials.

Main Methods:

• Synthesis of oligo[1,3-dibutadiynylene-1,3-(tetrafluoro)phenylene] and its conversion to fluorinated glassy carbon via thermal treatment.
• Fabrication of SPME fibers incorporating the synthesized fluorinated glassy carbon.
• Extraction of monohalogenated benzenes (fluorobenzene, chlorobenzene, bromobenzene, iodobenzene) and toluene from aqueous solutions using the developed SPME fibers.
• Analysis of extracted compounds and comparison of selectivity with commercial SPME fibers (PDMS, PDMS/DVB, PDMS/Carboxen).

Main Results:

• The extent of graphitization of the fluorinated glassy carbon increased with processing temperature.
• The novel fluorinated glassy carbon SPME fibers demonstrated selective extraction of monohalogenated benzenes over toluene.
• Selectivity for halogenated compounds followed the order: fluorobenzene < chlorobenzene < bromobenzene < iodobenzene, with optimal performance at processing temperatures below 400°C.
• Dispersive interactions were identified as a key factor in the retention mechanism of halocarbons on the fluorinated glassy carbon phase.
• The fluorinated glassy carbon SPME fibers exhibited higher selectivity for halogenated compounds compared to commercial SPME fibers, with an opposite selectivity trend observed.

Conclusions:

• Supported fluorinated glassy carbon SPME fibers represent a novel and effective material for selective extraction of halogenated aromatic compounds.
• The developed SPME fibers offer superior selectivity for halogenated benzenes compared to conventional commercial SPME materials.
• Further investigation into the retention mechanisms can lead to the design of even more advanced SPME materials for environmental and chemical analysis.