Preparation of gold nanoparticles and barium coordination polymer doped polypyrrole solid-phase microextraction coating for the detection of nitropolycyclic aromatic hydrocarbons

A stable gold nanoparticles (AuNPs) and barium coordination polymer (BaCP) doped polypyrrole (Ppy) solid phase microextraction coating was prepared by electrodeposition. It was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetry. The obtained coating exhibited broccoli-shape with many particles attached on it, and it could bear 300 °C. Five nitropolycyclic aromatic hydrocarbons (NPAHs) were selected as models to test its extraction property. Due to the π-π, metal ion-π interaction, hydrogen bonding and hydrophobic interaction between the target analytes and the coating, high extraction efficiency was observed. Under the selected conditions, by coupling with GC-FID detection limits of 0.92 ~ 4.16 ng/L (S/N = 3) and linear ranges of 10 ~ 3500 ng/L were achieved. The relative standard deviation for different coatings was 4.20 ~ 10.2%, and the relative standard deviation for the same coatings was 2.86 ~ 5.70%. The detection of the five NPAHs in water samples was successfully performed by using this method and the recoveries ranged from 80.3% to 115.6%.