A sensitive gas chromatographic assay for the determination of serum viloxazine concentration using a nitrogen-phosphorus-selective detector.
A gas-liquid chromatographic procedure for measuring the serum levels of the antidepressant viloxazine is described. The drug and the internal standard [imipramine (IMI)] are extracted from 1 ml serum. The method involves a three-step extraction, derivatization of viloxazine with acetic anhydride, and injection into a gas chromatograph equipped with a nitrogen-phosphorus-selective detector. The retention times for IMI and viloxazine were 4.7 and 6.1 min, respectively. The standard curves were linear over the 100- to 2,000-ng/ml range. The recovery averaged 64.5% and the lowest detection limit was 80 ng/ml. The within-run and day-to-day coefficients of variations were 11.9 and 12.5%, respectively, at 250 ng/ml, and 8.9 and 9.2%, respectively, at 1,500 ng/ml. The method is adequate both for single-dose pharmacokinetic studies and for monitoring serum viloxazine levels in chronically treated patients.
D000328:Adult; D002849:Chromatography, Gas / Q000295:instrumentation / Q000379:methods / Q000592:standards; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D009025:Morpholines / Q000097:blood*; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D012015:Reference Standards; D014745:Viloxazine / Q000097:blood* / Q000592:standards
D009025:Morpholines; D010758:Phosphorus; D014745:Viloxazine; D009584:Nitrogen