Abstract

This work is the extension to an earlier report of a model, which explained the normal  blood pH of 7.4 in terms of the octahedral packing of the six hydroxyl, OH^-, ions to one hydrogen, H⁺, ion that exist at that pH, as this would be the most, naturally, stable arrangement. The logical, possible shifts from the octahedral ideal are suggested to be to the next most stable and efficient natural structures, the other regular polyhedra (tetrahedron, cube, dodecahedron and the icosahedron), depending on the hydroxyl to proton ratio available. Polyhedral charge-structuring is suggested to help define a ‘polyhedral charge-packing pH zone’ (From pH = 7.30, for tetrahedral, to pH = 7.65 for dodecahedral packing), which lies in the neighborhood of the well known physiological pH range. Literature is cited in support of pH 7.65 as the extreme upper limit of tolerable alkalosis. Experimental results from studies on two acidotic diseases (Sickle cell disease, pH = 7.32 ± 0.08 and Asthma, pH = 7.29 ± 0.03) are presented as evidence of the tetrahedron-based tolerable, stable, low limit pH in acidosis. Some medical implications of these ideas are discussed. For instance, the model suggests that the generalized definition of metabolic acidosis as pH less than 7.3 (pH < 7.3) is informed by the underlying tetrahedral charge-packing structure at this pH, which would collapse immediately the blood pH falls below this critical threshold.

Key words: Blood, pH, polyhedral, hydroxyl, charge-packing, ions, disease states.