Determination of carboxylic acid salts in pharmaceuticals by high-performance liquid chromatography after pre-column fluorogenic labelling.
2-Bromoacetyl-6-methoxynaphthalene (Br-AMN) was used as a fluorogenic labelling reagent for high-performance liquid chromatographic (HPLC) analyses of pyroglutamic acid, 4-hydroxybutyric acid and thioctic acid in pharmaceutical formulations. The reaction was carried out in aqueous medium in the presence of a cationic surfactant to obtain the direct derivatization of the salts of 4-hydroxybutyric acid and thioctic acid or in acetonitrile for pyroglutamic acid. The resulting naphthacylesters were then chromatographed under reversed-phase (C-18) conditions and detected fluorimetrically (lambda exc, 300 nm; lambda em, 460 nm). The method proved to be suitable for the sensitive and selective analysis of commercial formulations of the cited acidic drugs.
Gatti
R
R
Dipartimento di Scienze Farmaceutiche, Università di Bologna, Italy.
Bousquet
E
E
Bonazzi
D
D
Cavrini
V
V
D002264:Carboxylic Acids / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000706:statistics & numerical data; D005456:Fluorescent Dyes; D009281:Naphthalenes; D004364:Pharmaceutical Preparations / Q000032:analysis*; D011761:Pyrrolidonecarboxylic Acid / Q000032:analysis; D012680:Sensitivity and Specificity; D012978:Sodium Oxybate / Q000032:analysis; D013678:Technology, Pharmaceutical; D008063:Thioctic Acid / Q000032:analysis
D002264:Carboxylic Acids; D005456:Fluorescent Dyes; D009281:Naphthalenes; D004364:Pharmaceutical Preparations; C084840:2-bromoacetyl-6-methoxynaphthalene; D008063:Thioctic Acid; D012978:Sodium Oxybate; D011761:Pyrrolidonecarboxylic Acid