title: Ultra-fast determination of caffeine, dipyrone, and acetylsalicylic acid by capillary electrophoresis with capacitively coupled contactless conductivity detection and identification of degradation products.
abstract: Capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C(4)D) was used for fast, simultaneous determination of dipyrone (DIP), caffeine (CAF), and acetylsalicylic acid (ASA). In the same run and in less than 1min, the degradation products from DIP and ASA were also detected. In addition, the usage of the CE-C(4)D system allowed, for the first time, the detection of methylamine as a degradation product of DIP. Capillary electrophoresis with electrospray mass spectrometry experiments were carried out in order to confirm the formation of methylamine. The limits of detection by CE-C(4)D were 5, 5, and 6μmolL(-1) for CAF, DIP, and ASA, respectively. The proposed method was applied to the analysis of these compounds in pharmaceutical formulations with similar results to those achieved by HPLC (p<0.05).
authors.affiliation: Instituto de Química, Universidade Federal de Uberlândia, Av. João Naves de Ávila, 2121 Uberlândia, MG, Brazil.
authors.forename: Mariana Cardoso
authors.initials: MC
authors.lastname: Marra
authors.affiliation: Instituto de Química, Universidade Federal de Uberlândia, Av. João Naves de Ávila, 2121 Uberlândia, MG, Brazil.
authors.forename: Rafael Rodrigues
authors.initials: RR
authors.lastname: Cunha
authors.affiliation: Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes, 748 São Paulo, SP, Brazil.
authors.forename: Denis Tadeu Rajh
authors.initials: DT
authors.lastname: Vidal
authors.affiliation: Instituto de Química, Universidade Federal de Uberlândia, Av. João Naves de Ávila, 2121 Uberlândia, MG, Brazil.
authors.forename: Rodrigo Alejandro Abarza
authors.initials: RA
authors.lastname: Munoz
authors.affiliation: Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes, 748 São Paulo, SP, Brazil.
authors.forename: Claudimir Lucio
authors.initials: CL
authors.lastname: do Lago
authors.affiliation: Instituto de Química, Universidade Federal de Uberlândia, Av. João Naves de Ávila, 2121 Uberlândia, MG, Brazil. Electronic address: emrichter@iqufu.ufu.br.
authors.forename: Eduardo Mathias
authors.initials: EM
authors.lastname: Richter
mesh_terms: D001241:Aspirin / Q000032:analysis*; D002110:Caffeine / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D004177:Dipyrone / Q000032:analysis*; D004553:Electric Conductivity; D019075:Electrophoresis, Capillary / Q000379:methods; D006868:Hydrolysis; D008744:Methylamines / Q000032:analysis
chemical_list: D008744:Methylamines; D002110:Caffeine; D004177:Dipyrone; C027451:methylamine; D001241:Aspirin
keywords: Aspirin; Capillary zone electrophoresis; Hydrolysis products; Mass spectroscopy; Metamizole