A hydrophilic-lipophilic triazine based hyper-crosslinked polymer for efficient enrichment of nitrobenzene compounds

Sensitive, accurate, and simultaneous determination of nitrobenzene compounds (NBs) in environmental water samples is of great significance due to their high risk to human health. In this work, a new triazine-based hyper-crosslinked polymer named CC-Py was constructed via the Friedel-Crafts reaction between cyanuric chloride (CC), pyridine (Py) and 1,2-dichloroethane. Due to its excellent stability, high surface area and hydrophilic-lipophilic (amphiphilic) structure, the CC-Py exhibited a high affinity toward the NBs (nitrobenzene, 2-nitrotoluene, 2,6-dimethylnitrobenzene, 3-nitrotoluene, 4-nitrotoluene, 3-nitrochlorobenzene, 4-nitrochlorobenzene, 2-nitrochlorobenzene, 2,4-dimethylnitrobenzene, 3-nitrobromobenzene, 4-nitrobromobenzene and 4-nitroiodobenzene). Then, a CC-Py based solid-phase microextraction coupled with gas chromatography-flame ionization detection was developed to detect the twelve NBs in real water samples. The results showed that the method had low limits of detection (0.20-0.50 μg L^-1), good reproducibility (relative standard deviations (RSDs) < 8.6%) and high enrichment factors (967-1590). The recoveries for the NBs in six different types of water samples were between 90% and 111% with the RSDs less than 7.5%. This work provides a facile and sensitive method for the determination of trace level of NBs in real water samples.