Ionically gelled alginate foams: physical properties controlled by type, amount and source of gelling ions

A new and flexible method for preparation of dry macroporous alginate foams with the capability of absorbing physiological solutions has been developed, which may find use within areas such as wound healing, cell culture, drug delivery and tissue engineering. The present study demonstrates how the gelation rate of the alginate and degree of ionic crosslinking can be utilized to control the physical foam properties. The rate of released Ca(2+)/Sr(2+) gelling ions available for interaction with the alginate was influenced by the concentration and physical characteristics of CaCO₃/SrCO₃ particles. The method of preparation of such foams allows, as described herein, tailoring of the pore structure, hydration properties and mechanical integrity in a manner not possible by other techniques.