THE ADSORPTION OF THE ADHESIVE PROTEIN OF THE BLUE MUSSEL MYTILUS-EDULIS-L ONTO TYPE 304L STAINLESS-STEEL

Adsorption measurements of the adhesive protein isolated from the blue mussel Mytilus edulis L onto type 304L stainless steel were performed . The adhesive protein is a high-molecular-weight biopolymer (100 kDa) that contains catecholic functionalities, which in principle are exce llent iron chelators. From these measurements, adsorption isotherms we re determined, and the maximum number of binding sites/m(2) and the af finity constant were calculated. These values were compared to those m easured for three other adsorbates onto type 304L stainless steel, nam ely, bovine serum albumin (BSA), L-3,4 dihydroxybenzoic acid (DHBA), a nd poly-L-lysine. Studies indicate that the mussel protein exhibits th e highest affinity constant for the stainless steel of all the adsorba tes and multilayer adsorption occurs at the mussel protein:metal inter face; the other adsorbates exhibit Langmuir-type monolayer adsorption. The mussel protein significantly inhibits dissolution of iron and chr omium metal from the stainless steel at pH 7.8, whereas the other adso rbates enhance it. These results indicate that the mussel protein form s a stable metal-protein complex at the surface of the metal that does not desorb into solution. (C) 1994 Academic Press, Inc.