title: Determination of caffeine and associated compounds in food, beverages, natural products, pharmaceuticals, and cosmetics by micellar electrokinetic capillary chromatography.
abstract: A method is described for quantitating caffeine, theobromine, theophylline, paracetamol, propyphenazone, acetylsalicylic acid, salicylic acid, and codeine phosphate in corresponding real samples of food, beverages, natural products, pharmaceuticals, and cosmetic preparations by micellar electrokinetic capillary chromatography. The separation is carried out at 25 degrees C and 25 kV, using a 20 mM phosphate buffer (pH 9.0), 80 mM sodium dodecyl sulfate, and 7.5% (v/v) acetonitrile. UV detection is at 210 nm. The method is shown to be specific, accurate (recoveries over the range 98.9-101.2%), linear over the tested range (correlation coefficients>or=0.9993), and precise (relative standard deviation below 2.1%). The method is applied for the quantitative analysis of these compounds in different foods, beverages, natural products, pharmaceuticals, and cosmetic products.
authors: Faculty of Pharmacy, Department of Pharmaceutical Biology, University of Ljubljana, Askerceva 7, 1000 Ljubljana, Slovenia. injacrade@gmail.com
authors: Rade
authors: R
authors: Injac
authors: Branislava
authors: B
authors: Srdjenovic
authors: Matevz
authors: M
authors: Prijatelj
authors: Marija
authors: M
authors: Boskovic
authors: Katarina
authors: K
authors: Karljikovic-Rajic
authors: Borut
authors: B
authors: Strukelj
mesh_terms: D000082:Acetaminophen / Q000032:analysis; D000983:Antipyrine / Q000031:analogs & derivatives / Q000032:analysis; D001241:Aspirin / Q000032:analysis; D001628:Beverages / Q000032:analysis*; D001688:Biological Products / Q000737:chemistry*; D002110:Caffeine / Q000032:analysis*; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D003061:Codeine / Q000032:analysis; D003358:Cosmetics / Q000737:chemistry*; D005504:Food Analysis / Q000379:methods*; D016014:Linear Models; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D020156:Salicylic Acid / Q000032:analysis; D013805:Theobromine / Q000032:analysis; D013806:Theophylline / Q000032:analysis
chemical_list: D001688:Biological Products; D003358:Cosmetics; D004364:Pharmaceutical Preparations; D000082:Acetaminophen; D002110:Caffeine; D013806:Theophylline; D020156:Salicylic Acid; D013805:Theobromine; C009077:propyphenazone; D001241:Aspirin; D000983:Antipyrine; D003061:Codeine