Ion-selective electrodes based on metalloporphyrins for gibberellic acid determination in agricultural products

• Tipo: Artigo em Revista Científica Internacional
• Data: 2003

Autores

Santos, EMG (Autor) Outra; Couto, CMCM (Autor) Outra; Montenegro, MCBSM (Autor) FFUP; Neves, MGPMS (Autor) Outra; Rebelo, SLH (Autor) Outra; Cavaleiro, JAS (Autor) Outra; Reis, BF (Autor) Outra

Revista

Título: Analytical and Bioanalytical Chemistry

Vol. 375

Páginas: 511-516

ISSN: 1618-2642

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 11 Citações

ISI Web of Science

Scopus - 14 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

CORDIS: Ciências da Saúde

Outras Informações

ID Authenticus: P-000-HSS

DOI: 10.1007/s00216-002-1717-9

Resumo (PT): This work describes the construction, evaluation and analytical application of electrodes selective to the gibberellate anion for the determination of gibberellic acid in agricultural products. Several types of PVC membrane electrodes without internal reference solution were prepared using the manganese(III) complex of meso -tetraphenylporphyrin (TPP) as ionophore and dibutyl phthalate (DBP), as plasticizer. The incorporation of lipophilic chemical species as additives, was also carried out aiming the evaluation of the response characteristics of the electrodes. To accomplish the analysis of commercial agricultural products a selective membrane composed of 28.0% (w/w) of PVC, 66.0% (w/w) of plasticizer and 6% (w/w) of ionophore was used, with no additive. This potentiometric unit presented a linear response between 10-4 and 10-1 mol L-1 in gibberellate, a slope of about m69 mV dec-1 and a reproducibility of about -1 mV day-1. The potentiometric analysis of gibberellic acid in commercial products was carried out by direct potentiometry and the results obtained were compared with those provided by HPLC. <br> <br> <a target="_blank" href="http://www.springerlink.com/content/mbk5dxey8y4ykpdh/?p=ce127455dd3d4586b1d974f9f988f692&pi=6 "> Texto integral </a> <br> <br>

Abstract (EN): This work describes the construction, evaluation and analytical application of electrodes selective to the gibberellate anion for the determination of gibberellic acid in agricultural products. Several types of PVC membrane electrodes without internal reference solution were prepared using the manganese(III) complex of meso-tetraphenylporphyrin (TPP) as ionophore and dibutyl phthalate (DBP), as plasticizer. The incorporation of lipophilic chemical species as additives, was also carried out aiming the evaluation of the response characteristics of the electrodes. To accomplish the analysis of commercial agricultural products a selective membrane composed of 28.0% (w/w) of PVC, 66.0% (w/w) of plasticizer and 6% (w/w) of ionophore was used, with no additive. This potentiometric unit presented a linear response between 10(-4) and 10(-1) mol L-1 in gibberellate, a slope of about -69 mV dec(-1) and a reproducibility of about +/-1 mV day(-1). The potentiometric analysis of gibberellic acid in commercial products was carried out by direct potentiometry and the results obtained were compared with those provided by HPLC.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 6