SUPERCRITICAL-FLUID EXTRACTION OF PRIORITY ORGANOTIN CONTAMINANTS FROM BIOLOGICAL MATRICES

The effect of different supercritical fluid extraction variables such as pressure (20-34 MPa), temperature (50-100 degrees C), modifier type (methanol, acetic acid, and toluene) with co-modifiers (e.g. tropolon e) and static extraction time (10-30 min) was evaluated for the recove ry of incurred butyltin compounds from a clam homogenate. The best ext raction conditions, obtained by a factorial fractional experimental de sign, were at low temperatures (50 degrees C) and high pressures (34 M Pa) in presence of acetic acid as static carbon dioxide modifier conta ining 0.2% of tropolone. Optimum extraction conditions were applied to the determination of incurred DBT, TBT and TPhT from a freeze-dried f ish tissue and a mussel homogenate yielding comparable results to thos e obtained by conventional solvent extraction techniques following a t issue solubilization but analysis time is reduced by factor of four. ( C) 1997 Elsevier Science B.V.