Flow injection potentiometric system for the simultaneous determination of inositol phosphates and phosphate: phosphorus nutritional evaluation on seeds and grains.
J Agric Food Chem
; 53(20): 7644-8, 2005 Oct 05.
Article
em En
| MEDLINE
| ID: mdl-16190610
ABSTRACT
A simple flow injection potentiometric (FIP) system, which uses a tubular cobalt electrode, has been developed for phosphorus nutritional evaluation of seeds and grains. Inorganic phosphorus, P(i), is determined using a 1 x 10(-2) mol.L(-1) potassium phthalate buffer solution adjusted at pH 4. A sensitivity of 47 mV/decade and an operating range from 10 to 1000 mg.L(-1) (1 x 10(-4)-1 x 10(-2) M) of dihydrogen phosphate are obtained. The inositol phosphates amount, which is referred to the organic phosphorus, P(org), is directly determined from extracts using a 1 x 10(-2) mol.L(-1) Tris-HCl buffer solution adjusted at pH 8. A sensitivity of 127 mV/decade and an operating range of 10-1000 mg.L(-1) (2.5 x 10(-4)-5 x 10(-3) M) of P(org) (expressed as inositol hexakisphosphoric acid monocalcium) are achieved. Some samples of seed and grain are analyzed by an ICP-OES and a spectrophotometric method to compare results to the developed flow system; no significant differences at the 95% confidence level are observed using a paired t test. Other samples such as animal nursing feed, soybean meal, and corn are also analyzed with the proposed FIP system, showing a good correlation to the ICP-OES values.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fosfatos
/
Potenciometria
/
Grão Comestível
/
Fósforo na Dieta
/
Análise de Injeção de Fluxo
/
Fosfatos de Inositol
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Revista:
J Agric Food Chem
Ano de publicação:
2005
Tipo de documento:
Article