Combination of ultrasonic-assisted dispersive liquid phase micro-extraction with magnetic dispersive solid-phase extraction for the pre-concentration of trace amounts of atrazine in various water samples

Herein, ultrasonic-assisted liquid phase micro-extraction in tandem with dispersive µ-solid-phase extraction was utilised for the determination of atrazine at µg L⁻¹ concentration levels. Initially, a liquid phase micro-extraction based on dispersion of organic solvent was used for the rapid extraction of atrazine from aqueous solution followed by the extraction organic solvent effectively collected from the solution by using C-18-magnetic nanoparticles without any requirement to centrifugation step. After the elution of the extracted targets from the magnetic nanoparticles, atrazine concentration was monitored by high-performance liquid chromatography with Ultraviolet detector at µg L⁻¹ level. The influencial parameters in the pre-concentration step were as follows: pH of solution, magnetic-based sorbent amount (mg) and 1-octanol volume (µL). Additionally, the selected data for the factors produced by the Box-Behnken design were: pH of sample: 9.0, sorbent amount: 22 mg and the extraction solvent volume: 36 µL. Relative standard deviations under the optimised conditions by the hybrid mentioned extraction method was determined to be <7% and the method detection limit for atrazine was calculated to be 0.3 µg L⁻¹. Limit of quantification was calculated to be 0.8 µg/L for the studied analyte.