Wettability of cross-linked collagenous biomaterials: in vitro study

Collagenous biomaterials can be treated by chemical and physical agents to decrease biodegradation rate. Treatments to collagen may modify surface properties and subsequently cell and platelet behaviour. Collagenous films were either uncross-linked and cross-linked by glutaraldehyde, formaldehyde or cyanamide and/or treated by a severe dehydration. Contact angles, platelet contacting assay and fibroblast morphology were investigated. After severe dehydration, wettability was diminished except for formaldehyde-cross-linked and severely dehydrated films. Glutaraldehyde-cross-linked collagen results in an increase in wettability. Platelets were similarly distributed, except on formaldehyde-cross-linked films that exhibited no platelet aggregation. Fibroblasts were in a spreading phase on most collagenous films. However, cytotoxicity was noticed on some aldehyde-cross-linked films. No direct relationship was found between contact angles and platelet-cell attachment.