The protein release profile is dependent on the particle size distribution. A) Compares two sub-groups “Small” (1600 g supernatant) and “Large” (Large; 550 g, 7 min pellet) with the most significant differences average diameters relative to unfractioned (UnFrac). The corresponding release profile from Small exhibited a 50% burst release and 40 day release period. Large exhibited an 18% burst release followed by a 75 day release period. In contrast, UnFrac exhibited a burst release of 30.3% with sustained release for 57 days. B) Groups with similar particle size distributions also exhibit comparable burst release, protein release rate and release period. “Low Spin Time & Force Sup” represents the 550 g, 2:15 min supernatant sub-group. C) Modest, yet statistically significant differences in particle size distribution also affects the release profile. Significant differences in cumulative protein release were observed at all time-points except for hours 1, 6 & 11 and days 3, 33 & 48 (p>0.05).