Method for the determination of 5,5-diphenylbarbituric acid and its separation from 1,3-dimethoxymethyl-5,5-diphenylbarbituric acid in plasma by high-performance liquid chromatography.
A method is described for the measurement of 5,5-diphenylbarbituric acid in plasma using high-performance liquid chromatography with UV detection. Briefly, the compounds are separated on a C18 reversed-phase column using a mobile phase of 50 mM sodium acetate (pH 4.5) and methanol. The flow-rate is 1.0 ml/min and 25 microl are injected and detected at 215 nm. The method is specific and sensitive in the range of concentrations tested, with a limit of quantification of 0.25 microg/ml. The calibration curves are linear for concentrations between 0.25 and 10 microg/ml. Intra-day and inter-day coefficients of variation are less than 8.5 and 10.5%, respectively, over the linear range. Intra-day and inter-day bias are less than 7.0 and 8.0%, respectively. A pharmacokinetic study conducted in male Beagle dogs administered 10 mg/kg of 1,3-dimethoxymethyl-5,5-diphenylbarbituric acid or 8 mg/kg of 5,5-diphenylbarbituric acid intravenously demonstrates the utility of this method.
Department of Pharmacology, Georgetown University Medical Center, Washington, DC 20007, USA.
D L
DL
Thacker
D R
DR
Abernethy
A
A
Raines
D A
DA
Flockhart
D000818:Animals; D000927:Anticonvulsants / Q000097:blood* / Q000493:pharmacokinetics; D001463:Barbiturates / Q000097:blood* / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004285:Dogs; D005069:Evaluation Studies as Topic; D007275:Injections, Intravenous; D010634:Phenobarbital / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics; D051381:Rats; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D000927:Anticonvulsants; D001463:Barbiturates; C044127:5,5-diphenylbarbituric acid; C114499:1,3-dimethoxymethyl-5,5-diphenylbarbituric acid; D010634:Phenobarbital