Effect of vanadocene dichlorides on the crystal growth of hydroxyapatite

The effect of vanadocenes, used as drugs for various therapeutic applications, on the crystal growth of hydroxyapatite was investigated at sustained supersaturation using the constant composition technique. All vanadocene dichlorides were found to inhibit crystal growth of hydroxyapatite possibly through adsorption onto the active growth sites for crystal growth. The apparent order for the crystallization was n = 2 thus, suggesting a surface-diffusion-controlled mechanism. The kinetic results favoured a Langmuir-type isotherm, suggesting a high affinity of vanadocene dichloride for hydroxyapatite.