A melamine-formaldehyde-resorcinol aerogel as the sorbent of in-tube solid-phase microextraction

Aerogels have attracted more and more attention in many fields due to the unique properties, including large surface area, high porosity, excellent adsorption, and low thermal conductivity. Based on the specific advantages, an organic aerogel was developed as the coating for solid-phase microextraction (SPME) in this work. Melamine-formaldehyde-resorcinol aerogel was in situ prepared on the surface of basalt fibers through the copolymerization reaction, the fibers were placed into a polyetheretherketone tube to achieve SPME tube. Coupled to high performance liquid chromatography (HPLC), the tube was investigated and exhibited good extraction selectivity towards polycyclic aromatic hydrocarbons (PAHs) by pi-pi stacking and hydrophobic interactions. Under the optimal conditions, an online in-tube SPME-HPLC method was established with satisfactory enrichment factors (1128-2016), wide linear ranges (0.03-30 mu g L-1 and 0.15-30 mu g L-1), low limits of detection (0.01-0.05 mu g L-1) and acceptable repeatability (RSD <= 3.9%, n = 5). The method was successfully applied to the determination of several PAH targets in real samples.