Determination of paracetamol (acetaminophen) in different body fluids and organ samples after solid-phase extraction using HPLC and an immunological method

A solid-phase extraction method routinely used for serum samples was improv ed and applied to the qualitative and quantitative determination of paracet amol in different body fluids, e.g. blood, urine, cerebrospinal fluid, syno vial fluid, vitreous humor, and in tissue samples. A very simple method sho wed best results: Body fluids were mixed with phenacetine as internal stand ard and phosphate buffer (pH 6.8). Then protein was precipitated using acet onitrile. After strong centrifugation the supernatant was transferred to a preconditioned Bakerbond C18-SPE-column. Elution with methanol without a pr ior washing step showed best recovery rates. The extracts were investigated using high-performance liquid chromatography with ultraviolet detection, a photometrical and an immunochemical method.