A PEG-based polymer matrix is developed within which biol. macromols. and living mammalian cells could be easily dispersed. Constraints placed upon such a matrix by a desire that it be generally processable in the presence of biol. macromols. and living cells include limiting temps. to physiol. or lower, working in oxygenated environments, avoiding exposure to cytotoxic monomers, avoiding exposure to org. solvents, and avoiding chem. reactions that readily modify functional groups found in proteins, such as carboxyls and amines. [on SciFinder (R)]