Provided herein are phenylboronate containing co-polymers (PCC), compositions containing PCC and polyvinyl alcohol (PVA), such compositions further including proteins, methods of making these compositions by water in oil polymerization, and methods of using the protein containing compositions for releasing proteins. Such phenylboronate containing co-polymers are of Formula I: where m, n, p, x, R1-R5, L, X1 and X2 are defined in the application.
