title: Chromatographic determination of N-acetyl-DL-tryptophan and octanoic acid in human albumin solutions.
abstract: Chromatographic procedures have been developed for determination of the stabilizers N-acetyl-DL-tryptophan and octanoic acid in human albumin solutions. N-Acetyl-DL-tryptophan and the internal standard, N-formyl-DL-tryptophan, were separated by liquid chromatography on a reversed-phase column with UV detection at 280 nm. Deproteinization and extraction were carried out with methanol. The extraction recovery at the level of 4.9 mM was 92.5 +/- 2.5% (S.D.) (n = 10), and the average coefficient of variation (C.V.) for replicate analyses of albumin solutions (mean = 2.57, 10.44 and 17.10 mM) was 1.10% (n = 27). Octanoic acid was determined gas chromatographically as its methyl ester, with nonanoic acid as the internal standard. The sample pretreatment included acidification, extraction with hexane and derivatization with methanol-sulphuric acid. The relative recovery from albumin solutions was 89.7 +/- 5.8% (S.D.) (n = 6), and replicate determinations of the compound yielded a C.V. of 5.5% (mean = 14.82 mM, n = 9).
mesh_terms: D000418:Albumins / Q000032:analysis*; D002210:Caprylates / Q000032:analysis*; D002849:Chromatography, Gas; D002853:Chromatography, Liquid; D004355:Drug Stability; D006801:Humans; D013997:Time Factors; D014364:Tryptophan / Q000031:analogs & derivatives* / Q000032:analysis
chemical_list: D000418:Albumins; D002210:Caprylates; C006392:N-acetyltryptophan; D014364:Tryptophan