Determination of organophosphorus pesticides in environmental water samples by dispersive liquid-liquid microextraction with solidification of floating organic droplet followed by high-performance liquid chromatography

• Published in: Analytical and bioanalytical chemistry 2010-07, Vol.397 (6), p.2543-2549
• Main Authors: Wu, Chunxia, Liu, Huimin, Liu, Weihua, Wu, Qiuhua, Wang, Chun, Wang, Zhi
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Applied sciences; Biochemistry; Calibration; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Chromatographic methods and physical methods associated with chromatography; Chromatography, High Pressure Liquid - methods; Chromatography, High Pressure Liquid - standards; Dispersive liquid-liquid microextraction based on solidification of floating organic droplet; Droplets; Exact sciences and technology; Food Science; Global environmental pollution; High performance liquid chromatography; Laboratory Medicine; Limit of Detection; Liquid chromatography; Mathematical analysis; Monitoring/Environmental Analysis; Organophosphorus Compounds - analysis; organophosphorus pesticides; Original Paper; Other chromatographic methods; Pesticides; Pesticides - analysis; Pollution; Reproducibility of Results; Solidification; Solvents; Water; Water Pollutants, Chemical - analysis; Water samples
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-010-3790-9

A simple dispersive liquid-liquid microextraction based on solidification of floating organic droplet coupled with high-performance liquid chromatography-diode array detection was developed for the determination of five organophosphorus pesticides (OPs) in water samples. In this method, the extraction solvent used is of low density, low toxicity, and proper melting point near room temperature. The extractant droplet could be collected easily by solidifying it in the lower temperature. Some important experimental parameters that affect the extraction efficiencies were optimized. Under the optimum conditions, the calibration curve was linear in the concentration range from 1 to 200 ng mL⁻¹ for the five OPs (triazophos, parathion, diazinon, phoxim, and parathion-methyl), with the correlation coefficients (r) varying from 0.9991 to 0.9998. High enrichment factors were achieved ranging from 215 to 557. The limits of detection were in the range between 0.1 and 0.3 ng mL⁻¹. The recoveries of the target analytes from water samples at spiking levels of 5.0 and 50.0 ng mL⁻¹ were 82.2-98.8% and 83.6-104.0%, respectively. The relative standard deviations fell in the range of 4.4% to 6.3%. The method was suitable for the determination of the OPs in real water samples.