title: Reducing the cost of phenytoin assays with in-house TDx reagents.
abstract: The Abbott TDx is frequently used for therapeutic drug monitoring of phenytoin concentrations, but reagent costs are high. In an attempt to reduce these costs, we investigated the preparation of in-house reagents. A commercial antiserum was available at reasonable cost and the fluorescent tracer was easily prepared. We describe the preparation of these reagents and their application to the TDx system. Substantially reduced costs were obtained using the in-house reagents.
authors.affiliation: Department of Chemical Pathology, Medical College of St Bartholomew's Hospital, London, UK.
authors.forename: D L
authors.initials: DL
authors.lastname: Colbert
authors.forename: G J
authors.initials: GJ
authors.lastname: Turner
authors.forename: J C
authors.initials: JC
authors.lastname: Gooch
mesh_terms: D002138:Calibration; D002855:Chromatography, Thin Layer; D003362:Cost-Benefit Analysis; D016903:Drug Monitoring / Q000191:economics*; D016650:Fluorescein-5-isothiocyanate; D016231:Fluorescence Polarization Immunoassay / Q000191:economics* / Q000379:methods; D006801:Humans; D007106:Immune Sera; D007202:Indicators and Reagents; D010672:Phenytoin / Q000097:blood*
chemical_list: D007106:Immune Sera; D007202:Indicators and Reagents; D010672:Phenytoin; D016650:Fluorescein-5-isothiocyanate