Study of the irreversible adsorption of proteins on polybutadiene-coated zirconia

The cause of irreversible adsorption of proteins on polybutadiene-coated zirconia is investigated by comparing the chromatographic properties of polybutadiene-coated zirconia with that of other reversed-phase packing materials such as bonded phase silica, polybutadiene-coated alumina and polybutadiene-coated silica. We find that the polybutadiene-coated zirconia has a micropore size distribution similar to that of the polybutadiene-coated alumina, from which some proteins can be eluted. Thus, the irreversible adsorption of proteins on polybutadiene-coated zirconia is not caused by entrapment of proteins in the micropores of the packing. The high hydrophobicity of the polybutadiene coating and the strong Lewis acid sites on the zirconia surface cause strong interactions between proteins and the stationary phase, the combination of which lead to irreversible adsorption of proteins on polybutadiene-coated zirconia.