Abstract
A solid-phase separation fluoroimmunoassay for primidone in plasma or serum was developed using antibodies coupled to magnetisable cellulose/iron oxide particles and a fluorescein-labelled primidone derivative as tracer. Endogenous fluorophores and other potentially interfering components in serum samples were reliably and completely removed at the time the antibody-bound and free fractions were being separated. The separation and wash steps were greatly facilitated by use of magnetic sedimentation. The assay reached equilibrium within 30 minutes; all normal reliability criteria were satisfied; and the results correlated closely with those of an established enzymoimmunoassay method. The assay is specific for primidone, and no detectable interference by all other commonly employed anticonvulsants was found at serum levels of 1 g/1.