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

• Type: Article in International Scientific Journal
• Date: 2003

Authors

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

Journal

Title: Analytical and Bioanalytical Chemistry

Vol. 375

Pages: 511-516

ISSN: 1618-2642

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 11 Citations

ISI Web of Science

Scopus - 14 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

CORDIS: Health sciences

Other information

Authenticus ID: 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.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6