A new type of collagen-hyaluronate (COL/HA) matrix was synthesized by cross
-linking collagen fibers with modified hyaluronate polymers bearing active
formyl groups. The resulting matrix is a three-dimensional scaffold consist
ing of interconnected pores with an average size of 40 mu m and a high pore
volume/surface area ratio. The covalent nature of the bond between the col
lagen fibers and the modified hyaluronate was demonstrated by extended elut
ion with phosphate buffered saline and by extraction in increasing ionic gr
adients. The fraction of covalently bound hyaluronate in the matrix ranged
from 5 to 25 w%. The total hyaluronate content of the COL/HA matrix affecte
d both the in vitro non-enzymatic and enzymatic degradation as well as the
in vivo turnover. When implanted in cranial defects in rats, the COL/HA mat
rix demonstrated good biocompatibility and exhibited greater osteoconductiv
e potential than matrices composed of either cross-linked collagen or cross
-linked hyaluronate alone. (C) 1999 Elsevier Science Ltd. All rights reserv
ed.