Phenytoin free fraction determination: comparison of an improved direct serum injection high-performance liquid chromatographic method to ultrafiltration coupled with fluorescence polarization immunoassay.
Recent developments in restricted-access media (RAM) liquid chromatography make the simultaneous determination of total and free phenytoin concentrations possible by direct injection of drug-containing serum samples. A comparison of phenytoin free fraction determination by ultrafiltration coupled with fluorescence polarization immunoassay (TDX) to an improved direct injection RAM-HPLC method is presented. Our improved method differs from those previously reported with regard to column type, mobile-phase composition, and column temperature. Replicate samples analyzed by each method yielded similar values for serum phenytoin free fraction.
Gurley
B J
BJ
Department of Pharmaceutics, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock 72205, USA.
Marx
M
M
Olsen
K
K
D000927:Anticonvulsants / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D016231:Fluorescence Polarization Immunoassay; D006801:Humans; D010672:Phenytoin / Q000097:blood*; D013056:Spectrophotometry, Ultraviolet; D014462:Ultrafiltration
D000927:Anticonvulsants; D010672:Phenytoin