Gels for encapsulation of biological materials

Abstract

This application is a divisional of U.S. application Ser. No. 10/761,180, filed Jan. 20, 2004 now abandoned which is a continuation of U.S. application Ser. No. 09/811,901, filed Mar. 19, 2001, now U.S. Pat. No. 6,911,227, which is a continuation of U.S. application Ser. No. 08/783,387, filed Jan.