Zinc(II)-based metal-organic nanotubes coating for high sensitive solid phase microextraction of nitro-polycyclic aromatic hydrocarbons.

Metal-organic nanotubes (MONTs) have great potential for solid phase microextraction (SPME) on account of high specific surface area, tunable pore sizes, and exceptional thermal and chemical stability. In this work, zinc (II)-based metal-organic nanotubes (Zn-MONTs) were used as an adsorbent for the SPME of nitro-polycyclic aromatic hydrocarbons (NPAHs) at trace levels from environmental water samples. Gas chromatography-mass spectrometry was used for sample analysis and key factors were investigated and optimized. Under optimal parameters, the developed method achieved low limits of detection (1.4-7.3 ng L-1), wide linear range (10-5000 ng L-1), and high enrichment factors (1510-17,684). In comparison to the PDMS and DVB/CAR/PDMS fiber for potential commercial use, the Zn-MONTs fiber obtained MS responses 2-9 times as high as those achieved by the commercial 100 µm PDMS and 0.2-2.3 times higher than 50/30 µm DVB/CAR/PDMS fiber did. The proposed method was successfully used in the analysis of NPAHs at trace levels in environmental samples.