Fabrication of bi-monomer copolymer of pyrrole-indole for highly efficient solid phase microextraction of benzene derivatives

A procedure for direct electrochemical deposition of poly(pyrrole-indole) on gold nanoparticles coated stainless steel wire was established, and the formation of copolymer was confirmed by infrared spectroscopy . The synthesized coating showed unique microstructure, excellent extraction efficiency (2–10 times of corresponding single-component coating), high thermal stability (up to 280   °C) and good durability (could be used for more than 200 times). As a novel and promising extraction coating, it was used for the headspace solid phase microextraction−gas chromatography detection of some benzene derivatives , including chlorobenzene , bromobenzene , p-bromotoluene, m-nitrotoluene and p-nitrotoluene. Under the optimized conditions, their GC peak areas were linear to their concentrations in the ranges of about 0.05–100   μg   L −1 , and the detection limits were 0.012–0.029   μg   L −1 (S/N = 3). The run-to-run RSDs were lower than 3.9% (n = 4), the fiber-to-fiber RSDs were 4.3–7.8% (n = 4). The proposed method was successfully applied to the determination of benzene derivatives mentioned above in real samples with good recoveries from 88.3% to 103.7%.