Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: 3/5/2007
Publication Date: 4/10/2007
Citation: Dahlen, G.M., Zito, C.A., Canfield, W.K. 2007. Novel determination of phytate by ion chromatography in wild rice and diet composites. Meeting Abstract. North Dakota Academy of Science. 61:48.
Technical Abstract: We have developed an ion chromatography (IC) assay using ultraviolet (UV) detection following post-column derivatization with ferric nitrate to determine phytate [inositol hexakis phosphate (iP6)] (1) (2) in wild rice samples and other diet composites. Samples were ground to a fine homogeneous powder, dried under vaccum, extracted with an acid (0.5 N hydrochloric) for 17 hours under constant agitation and centrifuged. Recoveries for phytate in wild rice extracts ranged from 96%-102%. To evaluate sensitivity, IC post-column derivatization was compared with the Association of Analytical Chemists (AOAC) “Official Method 986.11” results. Detection limits for phytate were 400ng for IC and 20ug AOAC respectively. Diet composites were analyzed by both methodologies and produced similar results with IC method yielding slightly higher results. AOAC method 986.11 is a tested method for phytate analysis. However, the method is laborious and does not have the sensitivity necessary for smaller samples that may require phytate quantification. Post-column derivatization has a 50-fold increase in sensitivity and requires only one mobile phase (isocratic) operation for phytate separation.