Presence of Carbonate in a Low-density Fraction of Diaphyseal Bone

Abstract

USING a method of centrifugation in liquids progressively increasing in specific gravity¹, it is possible to separate, from a sample of bone powder, fractions at various degrees of mineralization². These fractions, which can be recovered quantitatively, can then be analysed by appropriate chemical and biophysical techniques. We used infra-red spectroscopy for the examination of the carbonate present in bone, comparatively for a low specific gravity fraction (1.7 g/c.c.) and a pool of the high specific gravity fractions (1.8–2.3 g/c.c.) derived from diaphyseal bone samples of normal rats. It must be pointed out that less than 0.5 per cent of the samples belonged to the 1.7 gravity fraction. We used a Perkin–Elmer 221 infra-red spectrophotometer equipped with a sodium chloride prism. Potassium bromide pellets were prepared with various concentrations of whole unashed diaphyseal bone after separation.