Magnesium apatite (MA, (Ca9Mg)(PO4)6(OH)2) and Hydroxyapatite (HA) coatings were synthesized on Ti6Al4V substrates by a sol-gel dip coating method. Glucose and bovine serum albumin (BSA) were added to the standard simulated body fluid (SBF) separately to form organic-containing simulated body fluids. MA and HA coatings were immersed in standard and organic modified SBF for time periods of 4, 7, 14, 21 and 28 days at 37±1°C. The surface dissolution and deposition behavior of the coatings after soaking were examined with Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS). The results show that glucose in SBF has no apparent effect on the deposition of new apatite from the solution. BSA in SBF shows retardation effect on the deposition of apatite by forming a protein dominant globular layer. This layer inhibits the further deposition of apatite from SBF solution.