Determination of tannic acid by direct chemiluminescence in a FIA assembly.
The determination of tannic acid is performed in a FIA assembly on the basis of the analytical output obtained by oxidation of the acid. The analyte solution was daily prepared in a mixture of quinine as sensitiser and perchloric acid and it was injected into a pure water stream acting as a carrier. This solution merges with the mixture potassium permanganate in perchloric medium and the resulting chemiluminescence is monitored. The method was applied over the range 0.5-20 mg l(-1) of tannic acid with a LOD 100 mug l(-1). The reproducibility was 2.1% and the sample throughput 54 h(-1). The influence of foreign substances was studied and the new method is applied to the determination of tannic acid in pharmaceutical and galenic formulations in human urine and surface waters.
Gómez-Taylor Corominas
B
B
Departamento Quimica, Bioquimica y Biologia Molecular, University Cardenal Herrera-CEU, 46113 Moncada, Valencia, Spain.
García Mateo
J V
JV
Lahuerta Zamora
L
L
Martínez Calatayud
J
J