Optimization of a Dispersive Liquid-Liquid Microextration Method for Analysis of Chlorpyrifos in Urine Using the Chemometrics Method

The use of simple, low cost, high-efficiency microextraction methods are considered for sample preparation in forensic toxicology. Nowadays, the chemometrics technique can be used to determine the important and influencing factors on the response, to optimize the extraction methods. The aim of this study was to design and optimize a dispersive liquid-liquid microextraction (DLLME) method for the extraction of chlorpyrifos from the urine using a chemometrics method.
Materials & In this experimental study,  at first, a DLLME method for the extraction of chlorpyrifos in the urine sample was designed. Then, the Taguchi model was used for screening and investigating the role of effective factors on the extraction of chlorpyrifos from the urine and a central composite design was used to examine the interaction of these factors. After validation of the extracted data, chlorpyrifos was extracted from the urine using an optimized DLLME method and it detected and quantified using the high-performance liquid chromatography with photodiode array detector (HPLC-PDA).
The optimized DLLME-HPLC-PDA method was linear in the range of 0.5 to 4μg/ml, and the R2 coefficient was 0.9996. The minimum rates of detection and quantification ​​were calculated by 0.08 and 0.25μg/ml, respectively. The profitability of the method in the optimal condition was calculated by %95.6.
The optimized DLLME-HPLC-PDA method can be used as a simple, fast, inexpensive, sensitive and precise method for chlorpyrifos analyzing in urine specimens in clinical and forensic toxicology laboratories.