DETERMINATION OF TRACES OF PYRETHRINS AND PIPERONYL BUTOXIDE IN BIOLOGICAL-MATERIAL BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

A liquid chromatographic method for the determination of pyrethrins an d of the synergist piperonyl butoxide in human plasma after C-18 solid -phase extraction is described. UV detection was found to be sensitive enough to determine concentrations far below the limit of toxicity. W ith respect to future investigations concerning studies in biological materials, a column-switching system for sample preparation was develo ped and compared with solid-phase extraction. Both methods show compar able limits of detection, but the column-switching technique has the a dvantage of fully automating the system.