Analysis of Paraquat and Diquat in Human Blood by Capillary Electrophoresis

A rapid and simple method for the determination of the harbicides paraquat (PQ) and diquat (DQ) in whole blood by capillary electrophoresis (CE) has been developed. The separation of PQ and DQ was performed using citrate buffer (pH 5.0) and poly ethylene glycol coated fused silica capillary (CEP). Whole blood samples were injected into the CE after pretreatment of dilution and ultra-filtration. Linearity of quantification was obtained in the concentration range of 1-100 μg/ml for PQ and DQ in whole blood with the correlation coefficients of more than 0.999. The detection limits of PQ and DQ in whole blood were 0.5 μg/ml(s/n=3). The within-day precisions of peak areas for PQ and DQ in whole blood were 2%, and the between-day precisions were 3%, 6%, respectively.