Abstract
Paraquat was directly determined by high performance liquid chromatography (HPLC) with a UV detector using a reversed phase column packed with Nucleosil 5C18 (4.0 mm×0.15 m) and an ionpairing reagent in the mobile phase. Mobile phase consisted of 0.0075 M sodium 1-hexanesulfonate and 0.06 M sodium perchlorate in 15% methanol-water ; the pH was adjusted to 2.2 with phosphoric acid. Vanillic acid was used as an internal standard. The blood sample was mixed with equal volume of vanillic acid solution and a tenth part of acetic acid to the blood to prevent the choke of the column. After centrifugation, the supernatant was injected to HPLC. Recovery of paraquat obtained from the blood spiked at 50 μg/ml was 106.7±2.5%.
