Therapeutic drug monitoring of risperidone and 9-hydroxyrisperidone in serum with solid-phase extraction and high-performance liquid chromatography.

This laboratory developed a simple and efficient solid-phase extraction method that is combined with high-performance liquid chromatography for rapid and precise therapeutic monitoring of risperidone (Risperdal) in blood concentrations. The solid-phase extraction uses a mixed bed column. Sensitivity of the chromatographic method is 0.5 ng/ml (180 pmol/ml) of drug in serum, and separations can be performed in a 15-minute chromatographic run. Advantages of this approach include enhanced speed, sensitivity, and efficiency. A high level of sensitivity may be achieved because of the absence of interference from other drugs, metabolites, or serum components.