Separation and Determination of Paraquat and Diquat in Human Plasma and Urine by Magnetic Dispersive Solid Phase Extraction Coupled with High-Performance Liquid Chromatography.

Ou Sha,Hua Liu,Xiaobing Chen,Yuqing Zhu,Jiawei Yao,Bowen Cui

doi:10.1155/2020/7359582

Abstract

A magnetic dispersive solid phase extraction method coupled with high-performance liquid chromatography was proposed for the simultaneous separation and determination of paraquat (PQ) and diquat (DQ) in human plasma and urine samples. Based on the reduction of PQ and DQ to a blue radical and yellow-green radical by sodium dithionite in an alkaline medium, a fast colorimetric method was also developed for the fast detection of PQ or DQ. In this paper, CoFe2O4@SiO2 magnetic nanoparticles were used as the adsorbent for the magnetic dispersive solid phase extraction of paraquat and diquat, and these two analytes were found to be eluted directly from the adsorbent by NaOH solution. The main factors affecting the extraction efficiency including amount of extractant, extraction time, sample volume, sample solution pH, and elution volume were optimized. Under the optimized experimental conditions, the calibration curve was linear at a concentration range of 28.5–570.2 μg/L, and the correlation coefficient of paraquat and diquat was 0.9986 and 0.9980, respectively. The limits of detection of paraquat and diquat were 4.5 μg/L and 4.3 μg/L. The proposed MSPE-HPLC method was successfully applied to the detection of the paraquat and diquat in human plasma and urine with satisfied recoveries of PQ and DQ in the range of 87.5%–98.7%.

Highlights

Paraquat (PQ) and diquat (DQ) are nonselective contact herbicides, which have been widely used in the world for controlling the growth of weeds and grass in order to achieve high agricultural productivity (Figure 1) [1, 2]
Different approaches to measuring PQ or DQ concentration are available including highperformance liquid chromatography (HPLC) [8], high-performance liquid chromatography-mass spectrometry (HPLC–MS) [9], gas chromatography-mass spectrometry (GC–MS) [3], square wave voltammetry [10], and the spectrophotometric method [11]
Depending on the urgent needs for developing rapid and high selective methods to determine PQ and DQ with lower detection limits in plasma and urine samples, magnetic dispersive solid phase extraction coupled with HPLC-UV, CoFe2O4@SiO2 nanoparticles selected as the adsorbent, was developed for the separation and determination of PQ and DQ for the first time

Summary

Introduction

Paraquat (PQ) and diquat (DQ) are nonselective contact herbicides, which have been widely used in the world for controlling the growth of weeds and grass in order to achieve high agricultural productivity (Figure 1) [1, 2]. Different approaches to measuring PQ or DQ concentration are available including highperformance liquid chromatography (HPLC) [8], high-performance liquid chromatography-mass spectrometry (HPLC–MS) [9], gas chromatography-mass spectrometry (GC–MS) [3], square wave voltammetry [10], and the spectrophotometric method [11]. Depending on the urgent needs for developing rapid and high selective methods to determine PQ and DQ with lower detection limits in plasma and urine samples, magnetic dispersive solid phase extraction coupled with HPLC-UV, CoFe2O4@SiO2 nanoparticles selected as the adsorbent, was developed for the separation and determination of PQ and DQ for the first time. Based on the reduction of PQ and DQ to form a blue radical and yellow-green radical by sodium dithionite in alkaline medium, respectively, a rapid and simple method was established to colorimetrically detect PQ or DQ in human plasma and urine samples with naked eyes. is method proposed in this paper could offer a fast assessment of patient outcome based on the experimental data and helped the doctor to decide treatment strategies

Experimental

Results and Discussion

Method

Conclusion

Disclosure