Dispersive solid-phase extraction of selected nitrophenols from environmental water samples using a zirconium-based amino-tagged metal-organic framework nanosorbent.

This study has centered on the establishment of an efficient, simple and reliable dispersive solid-phase extraction method followed by an accurate trace determination of selected nitrophenols as a class of compounds with high toxicity and low degradability. To achieve the above goal, a zirconium-based amino-tagged metal-organic framework nanosorbent was synthesized, characterized and eventually employed for the extraction of two nitrophenols from various environmental water samples. Once the extraction of analytes had occurred, they were desorbed from the metal-organic framework sorbent using an appropriate mixed solvent followed by high-performance liquid chromatography with ultraviolet detection. Under the optimal extraction conditions, the calibration curves for the analytes were linear over the concentration range of 1-200 μg/L. The accuracy of the method was tested by the relative recovery experiments on the fortified real samples with the results falling within the range of 91 to 106%, while the corresponding precisions varied in the span of 4.6-9.0%. Based on a signal-to-noise ratio of 3, the method detection limits were determined to be 0.5 μg/L for both analytes.