Simple and sensitive determination of atrazine and its toxic metabolites in environmental water by carboxyl modified polyacrylonitrile nanofibers mat-based solid-phase extraction coupled with liquid chromatography-diode array detection.

Carboxyl modified polyacrylonitrile nanofibers mat (COOH-PAN NFsM) was prepared as a novel solid-phase extraction (SPE) adsorbent for the rapid and effective extraction of atrazine (ATZ) and its toxic metabolites deisopropylatrazine (DIA) and deethylatrazine (DEA) from environmental water samples. Without any pre-treatment but only with the simple filter, water samples passed through pre-conditioned COOH-PAN NFsM, which integrated extraction, purification and concentration into one single step, and the eluent was directly analyzed by high performance liquid chromatography-diode array detection (HPLC-DAD). Under the optimized conditions, the target analytes in 10mL of water sample could be completely extracted by only 4mg of COOH-PAN NFsM, and easily eluted using 400μL of methanol, indicating a high efficiency in both adsorption and desorption. Satisfactory linearity was achieved in the range of 0.4-40.0ngmL-1 for DIA, and 0.3-40.0ngmL-1 for DEA and ATZ. The limit of detection (LODs) were 0.12, 0.09 and 0.09ngmL-1 for DIA, DEA and ATZ, respectively. The recoveries ranged from 81.35 to 120.32%, with the intra-day and inter-day relative standard deviations of 4.03-9.81% even after the 6-cycle usage of NFsM. And, using just 10mL loading sample, the LOD had already satisfied the demand of surface water quality monitoring levels, revealing the good sensitivity of the proposed method.