Original scientific paper
https://doi.org/10.2478/aiht-2020-71-3292
Experimental central composite design-based dispersive liquid-liquid microextraction for HPLC-DAD determination of diazinon in human urine samples: method development and validation
Reza Mohammadzaheri
; Department of Chemistry, Science and Research Branch, Islamic Azad University, Kerman, Iran
Mehdi Ansari Dogaheh
; Department of Pharmaceutics, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran
Maryam Kazemipour
; Department of Chemistry, Science and Research Branch, Islamic Azad University, Kerman, Iran
Kambiz Soltaninejad
orcid.org/0000-0002-6770-1376
; Department of Forensic Toxicology, Legal Medicine Research Center, Legal Medicine Organization, Tehran, Iran
Abstract
Diazinon poisoning is an important issue in occupational, clinical, and forensic toxicology. While sensitive and specific enough to analyse diazinon in biological samples, current methods are time-consuming and too expensive for routine analysis. The aim of this study was therefore to design and validate a simple dispersive liquid-liquid microextraction (DLLME) for the preparation of urine samples to be analysed for diazinon with high performance liquid chromatography with diode-array detector (HPLC-DAD) to establish diazinon exposure and poisoning. To do that, we first identified critical parameters (type and volume of extraction and disperser solvents, pH, surfactant, and salt concentrations) in preliminary experiments and then used central composite design to determine the best experimental conditions for DLLME-HPLC-DAD. For DLLME they were 800 μL of methanol (disperser solvent) and 310 μL of toluene (extraction solvent) injected to the urine sample rapidly via a syringe. The sample was injected into a HPLC-DAD (C18 column, 250×4.6 mm, 5 μm), and the mobile phase was a mixture of acetonitrile and buffer (63:37 v/v, pH 3.2; flow rate: 1 mL/ min). Standard calibration curves for diazinon were linear with the concentration range of 0.5–4 μg/mL, yielding a regression equation Y=0.254X+0.006 with a correlation coefficient of 0.993. The limit of detection and limit of quantification for diazinon were 0.15 μg/mL and 0.45 μg/mL, respectively. The proposed method was accurate, precise, sensitive, and linear over a wide range of diazinon concentrations in urine samples. This method can be employed for diazinon analysis in routine clinical and forensic toxicology settings.
Keywords
disperser solvent; extraction solvent; high performance liquid chromatography; liquid phase microextraction; Taguchi orthogonal array
Hrčak ID:
236208
URI
Publication date:
27.3.2020.
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