The rapid extraction of paraquat from plasma using an ion-pairing technique.

A method for the quantitative extraction of paraquat from plasma is described. The method relies on the use of an organic-soluble ion pair of paraquat with dodecyl sulphate. The use of the extraction procedure in conjunction with the dithionite colour reaction gives a method which is suitable for emergency estimations with a sensitivity limit of 50 micrograms/l. The extraction procedure alone offers a new first step in the clean up of paraquat for analysis by other methods.