Calcification of α-elastin coacervates: A bulk property of elastin

Scanning electron microscopy and electron probe microanalysis studies are reported on thin sections of calcified coacervates of α-elastin. It is found that the capacity of elastin coacervates to initiate calcification is a bulk property of the coacervate and not limited to the serum-coacervate interface, that the calcium phosphate deposits act to bind the protein units together and slow the dissolution and spreading of the coacervate as it floats on an air-water interface, and that, within the limits of detectability, there is no involvement of sulfur. As the charged groups of α-elastin had been blocked, the initiation of deposition is due to neutral sites in the protein which are tightly bound to the calcium phosphate deposits.