deep eutectic solvents-based ultrasonic assisted dispersive liquid-liquid micro-extraction using nanoparticles for determination of dyes pre-concentration in water samples

A simple, green, rapid, sensitive, and eco-friendly ultrasonic-assisted deep eutectic solvent-dispersive liquid-liquid microextraction method (usa-des-dllme) was developed using modified nanoparticles (zno nps) for the separation and pre-concentration of crystal violet and congo red dyes in water samples, analyzed by uv-vis spectrophotometer. in this method, synthesized zno nps were characterized using various techniques, including uv-vis, ft-ir, fe-sem, edx, and afm. the optimum conditions for the quantitative recovery of the analytes included the effects of ph, type and volume of des, volume of zno nps, extraction time, thf, and centrifugation speed and duration. under the optimized experimental conditions, the relative standard deviation (rsd%) at a concentration of 0.05 µg ml-1 was found to be 2.71% and 2.77%. the limits of detection (lod) were 0.0351 µg ml-1 and 0.0561 µg ml-1, while the limits of quantification (loq) were 0.017 µg ml-1 and 0.0187 µg ml-1. the enrichment factors (ef) were 42.914 and 47.392, with the pre-concentration factor being 41.411 for crystal violet (cv) and congo red (cr) dyes, respectively, at 53.713. the intra- and inter-day precision of the method were calculated at concentrations of 0.3 and 0.5 µg ml-1. for crystal violet dye, the intra-day precision was 2.9% and 3.2%, while the inter-day precision was 2.8% and 3.4%. for congo red dye, the intra-day precision was 2.0% and 4.2%, with inter-day precision at 3.8% and 4.4%. the method was successfully applied to the determination of crystal violet and congo red dyes in water samples.