the zinc throughout the nhs edc reaction see examples the zinc ion is then removed by extensive dialysis for example the material can be dialyzed through a 500 mwco cellulose acetate dialysis tube against 50 phosphate buffered saline pbs water preferably at room temperature for 48 hours in a preferred embodiment the zinc chelator is a molecule that contains a diacetic acid moiety and thus a good chelator of certain divalent cations including zinc although these compounds are preferred any small organic molecule that has the ability to ligand or chelate a zinc molecule can sterically access the mmp active site without making any deleterious electrostatic interactions is capable of incorporation into a chelating peptide chepep the chelation process itself is not specific in that any zinc is potentially a chelation target possible chelators include but are not limited to edta egta dtpa cdta hedta nta citric acid salicylic acid and malic acid other chelators include peptides that can bind zinc for example peptides seq id no 9 cdic or seq id no 10 htith chelate the zinc moiety through interactions with the two cysteines seq id no 9 or the two histidines seq id no 10 these sequences are derived from the consensus structure of the zinc finger motif described by berg berg et al ann rev biophys biomol struct 1997 26 357 71 these peptides can be coupled to the targeting peptide via standard peptide synthesis in a preferred embodiment one of three zinc chelating molecules is covalently attached to one of the several timp derived peptides that comprise the present invention the chemical structures of these three zinc chelating molecules pyridine disulfide ethylenediaminetetraacetic acid psde amino iminodiacetic acid ida and 2.