EFFECT OF CROSS-LINKING AGENT ON THE RELEASE OF AN AQUEOUS MARKER FROM LIPOSOMES SEQUESTERED IN COLLAGEN AND CHITOSAN GELS

A system consisting of a combination of two carriers, i.e. phosphatidylcholine liposomes and collagen or chitosan, has been investigated to achieve both stability and slow release of an entrapped aqueous marker. The slow release of the entrapped aqueous marker bromothymol blue was prolonged by cross-linking the liposomes with a collagen/chitosan gel matrix after sequestration compared to sequestration without crosslinking. The release of bromothymol blue was inversely proportional to the degree of crosslinking. The release was faster with lesser crosslinks whereas the release slowed down considerably with an increase in the degree of crosslinking.