Peer-Reviewed Journal Details
Mandatory Fields
Essa, H; Magner, E; Cooney, J; Hodnett, BK
2007
November
Journal Of Molecular Catalysis B-Enzymatic
Influence of pH and ionic strength on the adsorption, leaching and activity of myoglobin immobilized onto ordered mesoporous silicates
Published
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Optional Fields
adsorption myoglobin ordered mesoporous silicates leaching immobilization MOLECULAR-SIEVES PROTEIN ADSORPTION ALUMINUM INCORPORATION ENZYME IMMOBILIZATION CYTOCHROME-C SBA-15 CHLOROPEROXIDASE HEMOGLOBIN SURFACTANT COPOLYMER
49
1-4
61
68
Myoglobin has been immobilized onto different ordered mesoporous silicates. The effect of the pH on the adsorption, leaching and activity was studied. The results showed that the maximum amount of protein was adsorbed at a pH 6.5, just below the protein isoelectric point (7 - 7.3). There was no effect of increasing ionic strength on the adsorption profile at different pH values. The adsorption is rationalized in terms of local electrostatic forces acting between the enzyme and the silica surface as well as hydrophobic interactions close to the protein isoelectric point, whereas at low pH the global charges give rise to protein - protein repulsion and at high pH enzyme - silica repulsion. Higher amounts of immobilized myoglobin were leached at a pH 4, while lower amounts were leached at pH 6.5. The catalytic activity of myoglobin immobilized onto SBA- 15 showed optimal activity at a pH 6.5 in comparison to a pH of 5 for the free form. (c) 2007 Elsevier B.V. All rights reserved.
1381-1177
10.1016/j.molcatb.2007.07.005
Grant Details