Patent ID: 8790678

Claim:
A substrate comprising a plurality of cross-linked, distinctly-formed layers, the plurality of cross-linked, distinctly-formed layers comprising at least three layers wherein the at least three layers comprise a first water soluble polymer layer, a second protein layer, and a third water soluble polymer layer, wherein the first water soluble polymer layer comprises a water soluble polymer that comprises a reactive group selected from the group consisting of sulfones, sulfoxides, sulfonates, sulfonamides, phosphonates and phosphonamides; the second protein layer comprises at least one protein that comprises at least one lipid binding site and at least one functional group selected from the group consisting of an amino group and a sulfhydryl group; and the third water soluble polymer layer comprises a water soluble polymer that comprises a reactive group selected from the group consisting of sulfones, sulfoxides, sulfonates, sulfonamides, phosphonates and phosphonamides; and whereby the second protein layer is disposed between the first water soluble polymer layer and the third water soluble polymer layer to cross-link the first water soluble polymer layer and the third water soluble polymer layer together to form the plurality of cross-linked, distinctly-formed layers.