Solid State 31P and 27Al NMR Studies of Model Membranes and Mammalian Brain: Possible Implications for Alzheimer’s Disease

Aluminum is the third most abundant element in the earth’s crust (just over 8% (w/w) of the earth’s crust) following oxygen (46.6%) and silicon (27.7%). Aluminum bonds to oxygen and silicon in aluminosilicate granites and clays (Bailar et al 1984; Cotton et al 1972; Smith 1971; Ganrot 1986). In spite of this large environmental abundance, and even though aluminum is capable of binding to many structures and substances in organisms, only small amounts of aluminum are ordinarily present in living plants and animals. This suggests the existence of molecular barriers to the absorption and tissue deposition of aluminum and/or efficient physiological mechanisms for its removal from living organisms. At neutral pH, aluminum minerals are extremely insoluble, and concentrations of dissolved aluminum are, therefore, low in both surface and subsoil water. The solubility of aluminum increases at lower pH values in the presence of calcium which has a buffering effect that facilitates aluminum dissolution (Ganrot 1986).