Comparison of a New Microcrystalline Aluminum Oxide Hydroxide and an Amorphous Aluminum Hydroxide for Binding to Phosphate, Proteins, Nucleotides, Lipids and Carbohydrates

抄録

Aluminum hydroxide gel (ALG), which is currently used as a phosphate-adsorbent, dissolves in gastric juice and the eluted aluminum ion has been suggested to be a causative agent of osteomalacia and encephalopathy. A new type of microcrystalline boehmite compound of aluminum oxide hydroxide with high acid resistance (named PT-A), has been developed by the author's group as a possible replacement for ALG.In the present study, the characteristic behaviors of PT-A and ALG toward various food components were compared at different pH's to get information on possible interference with phosphate adsorption onto the adsorbents by food components. The order of adsorption of food components per unit mass of PT-A was : proteins>nucleotides>lipids>carbohydrates. The order with ALG, with a minor exception, was the same as that with PT-A. However, the amounts of materials adsorbed on PT-A were generally much less than those on ALG. When phosphate was mixed with a synthetic milk as a model standard meal and exposed to the two adsorbents, phosphate-adsorption was entirely unaffected; however, the phosphate adsorption capacity of ALG was much less than that of PT-A. In conclusion, PT-A has a higher capacity for adsorbing phosphate, and adsorbs food components to a lesser extent than ALG. Phosphate-adsorption onto PT-A was not subject to interference by food components.