encapsulation methods chang et al u s pat no 5 084 350 discloses microcapsules enclosed in a larger matrix where the microcapsules are liquefied once the microcapsules are within the larger matrix tsang et al u s pat no 4 663 286 discloses encapsulation using an alginate polymer where the gel layer is cross linked with a polycationic polymer such as polylysine and a second layer formed using a second polycationic polymer such as polyornithine the second layer can then be coated by alginate u s pat no 5 762 959 to soon shiong et al discloses a microcapsule having a solid non chelated alginate gel core of a defined ratio of calcium barium alginates with polymer material in the core u s pat nos 5 801 033 and 5 573 934 to hubbell et al describe alginate polylysine microspheres having a final polymeric coating e g polyethylene glycol peg sawhney et al biomaterials 13 863 1991 describe alginate polylysine microcapsules incorporating a graft copolymer of poly l lysine and polyethylene oxide on the microcapsule surface to improve biocompatibility u s pat no 5 380 536 describes microcapsules with an outermost layer of water soluble non ionic polymers such as polyethylene oxide u s pat no 5 227 298 to weber et al describes a method for providing a second alginate gel coating to cells already coated with polylysine alginate both alginate coatings are stabilized with polylysine u s pat no 5 578 314 to weber et al provides a method for microencapsulation using multiple coatings of purified alginate u s pat no.