From porous aromatic frameworks to nanoporous carbons: A novel solid-phase microextraction coating

A novel nanoporous carbon (NPC) was constructed by utilizing the porous aromatic framework-6 (PAF-6) as both the template and carbon source along with KOH as a chemical activator. The newly-synthesized PAF-6 derived nanoporous carbon (PAF-6-NPC) was then employed as a solid-phase microextraction (SPME) fiber coating. Coupled with gas chromatography-flame ionization detection, the PAF-6-NPC fiber-based SPME method exhibited large enhancement factors, low limits of detection, good linearity and acceptable repeatability for the determination of some n-alkanes in various water and soil samples. The method recoveries for the n-alkanes were in the range of 89.5-102.9% for water and 86.0-104.5% for soil samples, respectively. The PAF-6-NPC coated fiber showed no obvious decrease of the extraction efficiency for the analytes after 100 replicate extractions. The PAF-6-NPC fiber-based SPME method was successfully applied for the determination of n-alkanes in water and soil samples.