Utilize este identificador para referenciar este registo: http://hdl.handle.net/10400.14/9990
Título: Development of a chromatographic low pressure flow injection system:Application to the analysis of methylxanthines in coffee
Autor: Santos, João Rodrigo
Rangel, António O. S. S.
Palavras-chave: Low pressure chromatography
Flow injection
Coffee
Methylxanthines
UV spectrophotometry
Data: 2012
Editora: Elsevier
Citação: SANTOS, João Rodrigo; RANGEL, António O. S. S - Development of a chromatographic low pressure flow injection system : Application to the analysis of methylxanthines in coffee. Analytica Chimica Acta. ISSN 00032670. Vol. 715, (2012), p. 57–63
Resumo: In this work, the coupling of a commercial monolithic column to a traditional low pressure FIA system is proposed for the analysis of theobromine, theophylline and caffeine in coffee brewed samples using UV detection. The parameters mobile phase composition, flow rate and loop volume were evaluated and discussed considering the various chromatographic parameters in order to enable resolution of the methylxanthines studied within the coffee brewed sample matrix. The analyses of methylxanthines in coffee brewed samples by the proposed methodology were in good agreement with those obtained by the reference procedure based on HPLC. Relative errors were below 6% for all samples analyzed. Detection limits in the selected experimental conditions were within 10−6M range for theobromine and theophylline, and 10−5M for caffeine. The determination rate of the three methylxanthines for coffee brewed samples was ca of 10 h−1. The main advantage of the proposed flow system was the possibility to perform chromatographic separations in low pressure flow systems. This substantial improvement was achieved due to the compatibility of monolithic columns within the flow injection system surpassing in this way one of the main handicaps of traditional flow analysis systems. Additional features of the strategy presented were low cost, efficiency, high versatility and low reagent consumption comparing to HPLC methodologies usually followed in the case study herein presented.
Peer review: yes
URI: http://hdl.handle.net/10400.14/9990
Versão do Editor: doi:10.1016/j.aca.2011.12.002
Aparece nas colecções:CBQF - Artigos em revistas internacionais com Arbitragem / Papers in international journals with Peer-review

Ficheiros deste registo:
Ficheiro Descrição TamanhoFormato 
AI30.pdf398,82 kBAdobe PDFVer/Abrir    Acesso Restrito. Solicitar cópia ao autor!


FacebookTwitterDeliciousLinkedInDiggGoogle BookmarksMySpace
Formato BibTex MendeleyEndnote Degois 

Todos os registos no repositório estão protegidos por leis de copyright, com todos os direitos reservados.