Metal chelating compositions and methods for controlling the growth or activities of a living cell or organism

A chelating composition comprising:

• a carrier material, and
• one or more suitable metal binding chemical groups having iron chelating activity affixed to or incorporated into the structure of the carrier material;
• wherein the one or more suitable metal binding chemical groups is 3-hydroxy-1-(β-methacrylamidoethyl)-2-methyl-4(1H)-pyridinone (MAHMP);
• wherein the carrier material comprises vinylpyrrolidone or dimethylacrylamide;
• wherein the chelating composition is formed by a first monomer group comprising a metal binding monomer representing the metal binding chemical group copolymerized with a suitable second monomer group representing the carrier material such that the resulting co-polymer remains soluble in aqueous solution and has iron chelating activity;
• wherein the chelating composition has a minimum molecular weight sufficiently large so as not to be normally taken up into the intra-cellular aspects internal to a cell membrane of a living cell and is able to bind iron;
• and
• wherein the chelating composition remains substantially soluble in the aqueous medium with its bound iron in the external cellular environment of the living cell thereby preventing uptake of the bound iron into the intra-cellular aspects internal to the cell membrane of the living cell.