<p>A process for forming microcarriers includes contacting an initiator-conjugated microcarrier base with one or more monomers and activating the initiator to initiate polymerization and to graft a polymer from the base via the initiator or a remnant thereof. At least one of the monomers is conjugated to a polypeptide so that incorporation of the monomer into the forming polymer conjugates the polypeptide to the polymeric coating as it is formed in situ.</p>
