Patent ID: 8142835

Claim:
A process for coating a medical article comprises the steps of: (a) providing an uncoated medical article, wherein the article comprises a hydrophobic bulk material made of a silicone hydrogel containing carboxylic acid groups; (b) contacting the medical article with a C 2 -C 4 alcohol for a predetermined period of time; (c) contacting the medical article treated in step (b) with a solution comprising chitosan to form a non-covalently attached coating of chitosan on the medical article; (d) contacting the medical article with the chitosan coating in a lens package containing a packaging solution comprising a crosslinking agent selected from the group consisting of aliphatic C 2 -C 10 -dialdehydes, formaldehyde and genipin; and (e) autoclaving said package with the medical article and the packing solution therein, wherein the chitosan coating the medical article is covalently attached through the crosslinking agent to the carboxylic acid groups on the medical article surface, wherein the resultant medical article has a hydrophilicity characterized by an average water contact angle of about 80 degrees or less.