Freeze-drying yields stable and pure amorphous calcium carbonate (ACC)

Abstract

A simple synthetic method is presented for the precipitation of high purity, dry amorphous calcium carbonate (ACC) based on freeze-drying saturated, counter ion free CaCO3 solutions, where the ACC produced shows an extended atmospheric stability. Translation of the methodology to amorphous calcium phosphate demonstrates the generality of the approach. © 2013 Royal Society of Chemistry.