The present invention relates to biscarbodiimides, thiourea derivatives, urea
derivatives, and cross-linked hyaluronan derivatives having at least one intramolecular
disulfide bond, and methods of preparation thereof. The invention also includes
thiolated hyaluronan derivatives and salts thereof having at least one pendant
thiol group or a modified pendant thiol group, and methods of preparation thereof.
An example of a modified pendant thiol group is a sulfhydryl group linked to a
small molecule such as a bioactive agent, for example a drug or pharmaceutically
active moiety. A hyaluronan derivative having a sulfhydryl group linked to a pharmaceutically
active moiety is useful as a sustained or controlled release drug delivery vehicle.
Compositions containing the hyaluronan derivatives of the invention can reversibly
viscosify in vivo or in vitro, in response to mild changes in condition, and are
thus useful in ophthalmic surgery and in tissue engineering.
