title: Flow injection potentiometric determination of saccharin in dietary products with relocation of filtration unit.
abstract: A flow injection potentiometric procedure for saccharin determination in dietary products is proposed. Saccharin is precipitated as mercurous saccharinate and the excess of the mercurous cation is potentiometrically measured using a silver wire coated with a mercury film as the working electrode. A filter unit is used to avoid contact between the precipitate and the electrode surface. With relocation in the flow manifold, the accumulated precipitate is removed on-line. Sucrose, glucose, aspartame, sodium cyclamate and sodium benzoate do not interfere when present in amounts similar to those observed in commercial products. Results are comparable with those obtained by UV-spectrophotometry and the correlation coefficient between methods is equal to 0.9930. A linear relationship between DeltaE (mV) and the logarithm of saccharin concentration was obtained in the saccharin concentration range 2 x 10(-3) - 1 x 10(-2)M. The sampling frequency is 60/hour and only 0.76 mg of Hg(2+)(2) is consumed in each determination.
authors.affiliation: Departamento de Química, Universidade Federal de São Carlos, Caixa Postal 676, CEP 13565-905, Sáo Carlos, SP, Brazil.
authors.forename: O
authors.initials: O
authors.lastname: Fatibello-Filho
authors.forename: J A
authors.initials: JA
authors.lastname: Nóbrega
authors.forename: A J
authors.initials: AJ
authors.lastname: Moraes Guaritá-Santos