An automatic titration setup for the chemiluminometric determination of the copper complexation capacity in opaque solutions

Autor(es)

Lima, Manoel J. A. ^[1] ; Reis, Boaventura F. ^[1] ; Zagatto, Elias A. G. ^[1] ; Kamogawa, Marcos Y. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Ctr Nucl Energy Agr, POB 96, BR-13400970 Piracicaba, SP - Brazil

^[2] Univ Sao Paulo, Luiz de Queiroz Coll Agr, Av Padua Dias 11, BR-13418900 Piracicaba, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Talanta; v. 209, MAR 1 2020.
• Citações Web of Science: 0

Resumo

An automatic titration setup exploiting flow analysis was proposed for the evaluation of the copper complexation capacity of highly opaque substances (milk and humic substances). The binary search approach was implemented in a flow-batch analyzer, in order to add the in-line selected titrant (e.g. copper ions) volumes to the sample. When the titration end-point was surpassed, the free metal ions catalyzed the reaction of luminol with hydrogen peroxide, yielding the chemiluminescence, which was quantified even in solutions of high opacity. Accuracy was assessed through addition/recovery tests involving classical complexing species (EDTA, DTPA and DTTC), and recoveries ranged from 96% to 115%. The proposed system requires low amounts of reagents and samples (0.42 mg of luminol, 82 mu g H2O2, 1.10 mL of sample) per titration run, meaning ca. 12 mL of effluent per titration, and yields precise results (5% r.s.d.) at a sampling throughput of 43 h(-1). (AU)

• Processo FAPESP: 11/23498-9 - Sistemas avançados de análises químicas em fluxo: aplicações nas áreas tecnológica, agronômica e ambiental
• Beneficiário: Elias Ayres Guidetti Zagatto
• Linha de fomento: Auxílio à Pesquisa - Temático