QUANTIFICATION OF POLYCYCLIC AROMATIC-HYDROCARBONS AND POLYCHLORINATED DIBENZO-P-DIOXINS IN HUMAN SERUM BY COMBINED MICELLE MEDIATED EXTRACTION (CLOUD-POINT EXTRACTION) AND HPLC

Quantification of polycyclic aromatic hydrocarbons (PAHs) and polychlo rinated dibenzo-p-dioxins (PCDDs) usually requires preconcentration an d cleanup prior to analysis. These procedures often involve using larg e amounts of toxic organic solvents. The sample preparation from serum is even more complex because of the coextraction of lipids and other nonpolar serum components. We describe the unprecedented use of cloud- point extraction to preconcentrate, extract, and clean up PAHs and PCD Ds from human serum using the nonionic surfactant Triton X-100. The sa mples were analyzed by highperformance Liquid chromatography with ultr aviolet detection. The phase separation was induced by the addition of salt to the micellar serum solutions. The surfactant-rich phase was t reated with acetonitrile and water to precipitate and remove some of t he unwanted substances in the serum sample extract without significant ly affecting the recoveries of the analytes. The favorable characteris tics of cloud-point extraction discussed here strengthen its potential use as an alternative to other techniques of separation.