Efficient solid phase microextraction of organic pollutants based on graphene oxide/chitosan aerogel

Area of Science:

• Analytical Chemistry
• Materials Science
• Environmental Science

Background:

• Developing high-performance solid-phase microextraction (SPME) coatings for diverse organic pollutants remains a challenge in sample preparation.
• Existing commercial SPME fibers often have limitations in extraction efficiency and analyte range.

Purpose of the Study:

• To design and synthesize a novel, stable chitosan cross-linked graphene oxide (GOCS) aerogel coating for SPME.
• To evaluate the extraction performance of the GOCS-coated SPME fiber for various organic pollutants.

Main Methods:

• Synthesis of a stable chitosan cross-linked graphene oxide aerogel.
• Coating the synthesized aerogel onto SPME fibers.
• Extraction and analysis of target analytes including polycyclic aromatic hydrocarbons (PAHs), pesticides, and polychlorinated biphenyls (PCBs).

Main Results:

• The GOCS aerogel exhibited interpenetrated meso- and macropores, providing a large surface area and accessible functional groups.
• Extraction capacities of GOCS-coated SPME fibers were 0.5-13 times higher than commercial fibers (PDMS, PDMS/DVB).
• Superior analytical performance for PAHs was achieved, with wide linearity (0.5-1000 ng L⁻¹), high enhancement factors (311-3740), and low limits of detection (0.03-1.28 ng L⁻¹).

Conclusions:

• The GOCS aerogel is a promising novel coating material for SPME applications.
• The GOCS-coated SPME fiber demonstrated effective determination of PAHs in real water samples with good recoveries (91.6%-110%).
• The enhanced performance is attributed to hydrophobic, π-π, halogen bond, and hydrogen bond interactions.