Abstract: Crosslinked biocompatible compositions comprising an ionically crosslinked component and a covalently crosslinked component for encapsulating biologics are disclosed. In accordance with the present invention, also disclosed are crosslinkable biocompatible mixtures comprising an ionically crosslinkable component and a covalently crosslinkable component. Methods for encapsulating biologics with the crosslinked and crosslinkable biocompatible compositions are provided. Also, retrievable macrocapsules for encapsulating microcapsules or biologics are disclosed.