ADSORPTION-ISOTHERMS OF VOLATILE ORGANOCHLORINE POLLUTANTS ON GEOMATERIALS

The analysis of drugs contained in biological matrices is generally pe rformed by gas chromatography coupled with mass spectrometry. Because of these complexity of these matrices a sample preparation step is nec essary. Subcritical fluid extraction has been developed for the determ ination of opiates (morphine, 6-monoacetylmorphine, codeine and ethylm orphine) in urine and hair. This procedure has been compared to conven tional techniques for this kind of matrice. For urine, classical solid phase extraction with a mired mode silica is the method of choice, ev en if subcritical fluid extraction gives some comparable results. In t ire case of hair, which is a complementary matrice, subcritical fluid extraction shows numerous advantages in regard to classical procedures : analysis time reduced, sample handling simplified and on-line coupli ng with chromatography possible. Finally, applications of real cases a re presented for the analysis of opiates, cocaine and its major metabo lite (the benzoylecgonine) and methadone contained in hair. In the cas e of opiates, a quantitative determination has been carried out on a l inear dynamic range of concentrations (between 0.25 to 5.0 ng/mg). Goo d coefficients of variation (between 3 to 12%) have been obtained. The limits of detection and quantification are respectively of 0.03 ng/mg and 0.1 ng/mg for codeine, ethylmorphine and morphine. These values a re multiplied by a factor of 2 for 6-monoacetylmorphine.