Patent ID: 7067272

Claim:
A thin membrane for measuring matrix metalloproteinase 7 (MMP-7) protease activity in a tissue slice or one or more cells, the membrane being formed on a support, and comprising at least one substance selected from the group consisting of a transferrin derivative and an albumin derivative, wherein said substance is crosslinked and/or substantially water-insoluble; wherein said transferrin derivative is obtained by: oxidation of a disulfide bond, cleavage of a disulfide bond with sulfite ion, or cleavage of a disulfide bond with a reducing agent, followed by S-alkylation; and wherein said albumin derivative is obtained by: oxidation of a disulfide bond, cleavage of a disulfide bond with sulfite ion, and cleavage of a disulfide bond with a reducing agent, followed by S-alkylation.