New Cellular Insights (IMAGE) Washington University in St. Louis Caption Calcium phosphate mineralization occurs in both extra- and intrafibrillar spaces of collagen (left and right images, respectively). Engineers at Washington University in St. Louis experimentally proved how the confined collagen structure contributes to reducing thermodynamic energy barrier to intrafibrillar nucleation for bone mineralization. Credit Washington University in St. Louis Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.