CHARACTERIZATION OF THE MORPHOLOGY OF HYDROXYAPATITE PRECIPITATED IN THE PRESENCE OF PROTEINS BY TEXTURE ANALYSIS OF SCANNING ELECTRON-MICROGRAPHS

Hydroxyapatite (HAP) was precipitated from solutions containing dissolved proteins at a range of concentrations, and the precipitates examined by scanning electron microscopy. In the absence of protein, HAP formed granular aggregates; however, as protein concentration was increased the size of these aggregates decreased, and the surface appeared smoother. This effect was measured by the spatial grey level method of image texture analysis in which texture parameters (energy, entropy, inertia and local homogeneity) are calculated from a co-occurrence matrix. A co-occurrence matrix was calculated from each digitized scanning electron micrograph. Energy, entropy and local homogeneity were linearly correlated with the protein concentration in the original solution from which the HAP was precipitated.