Determination of vitamins in food-matrix Standard Reference Materials

In recent years, the National Institute of Standards and Technology (MIST) has developed several food-matrix Standard Reference Materials (SRMs) chara cterized for vitamins and other organic nutrients. MIST uses several "modes " for assignment of analyte concentrations in SRMs, one of which includes t he use of data provided by collaborating laboratories. Certification modes and liquid chromatographic methods that were used by MIST for value assignm ent of vitamin concentrations in recently introduced food-matrix SRMs are d escribed in this paper. These materials and methods include vitamins D and E in coconut oil (SRM 1563) by gravimetry and multi-dimensional liquid chro matography (LC); vitamins A, E, and several B vitamins by reversed-phase LC and vitamin C by ion-exchange chromatography in infant formula (SRM 1846); and carotenoids and vitamins A and E by reversed-phase liquid chromatograp hy in a baby food composite (SRM 2383). (C) 2000 Published by Elsevier Scie nce B.V.