Abstract
Proteins often adsorb tightly to metal surfaces. Such a tight adsorption of protein leads to fouling of the wall surface of manufacturing equipment in food and drug manufacturing processes. The author has been engaged in the study of the adsorption behavior and mechanism of protein to metal (oxide) surfaces and the development of cleaning techniques that can remove adsorbed protein absolutely from metal surfaces under mild conditions. The results of the investigation to date have revealed that the electrostatic interactions via acidic amino acid residues of protein largely contribute to the tight adsorption. As for cleaning technique, a novel one that involves the use of hydroxyl radicals (・OH) generated by the electrolysis of hydrogen peroxide(H2O2-electrolysis cleaning) has been developed. It was demonstrated that the irreversibly-adsorbed proteins on metal (oxide) surfaces (stainless steel, titanium, and etc.) could be absolutely removed within a few minutes by the H2O2-electrolysis treatment at room temperature. The influences of various treatment factors on the removal behavior in H2O2-electrolysis cleaning were investigated.
