Two methods are described for the determination of iron in multivitamin preparations, formulated with either ferrous sulfate, ferrous fumarate, or ferrous gluconate. In the first procedure, an automated colorimetric procedure, iron is determined with 2,4,6-tripyridyl triazine in a buffered solution. In the second procedure, an X-ray emission spectrometer is used. Samples, analyzed as solutions, are placed in liquid sample cells and counted for 100 sec. Following sample preparation, approximately 20 samples can be assayed per hour with the automated procedure as compared to four (in duplicate) by X-ray emission.
HE DETERMINATION of iron in multivitamin
T preparations requires the use of assay procedures that are not affected by other minerals, vitamins, or formulation excipients. I n achieving this, X-ray emission spectroscopy has given satisfactory results in our laboratories over a long period of time. Requests for large numbers of iron assays in formulation studies and in single tablet or unit dosage assays, however, prompted the use of an automated chemical assay procedure. This report describes two methods for the determination of iron in multivitamin preparations, formulated with either ferrous sulfate, ferrous fumarate, or ferrous gluconate. I n the first procedure, an automated colorimetric procedure, iron is determined with 2,4,6-tripyridyl triazine in a buffered solution essentially as described by Zak et al. (1).
I n the second procedure, a General Electric X-ray emission spectrometer is used. Samples, analyzed as solutions, are placed in a liquid sample cell and are counted for 100 sec.