title: Exfoliation of montmorillonite in protein solutions.
abstract: In the study we demonstrate a method to obtain stable, exfoliated montmorillonite-protein complexes by adsorption of the proteins extracted from hen-egg albumen. Analysis of the process by means of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed that the complexes are formed by sequential adsorption of ovotransferrin, ovalbumins, ovomucoid and lysozyme on the surface of the silicate. Structural studies performed by X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicated that the adsorption of ovotransferrin and albumins is accompanied by disintegration of clay stacks into discrete platelets. Further analysis by dynamic light scattering (DLS) revealed that at protein to silicate weight ratios exceeding 20, the synergistic adsorption of albumen components leads to reaggregation of silicate platelets into disordered, microgel-like particles. By means of DLS it was found that exfoliation predominantly leads to formation of particles with average hydrodynamic radii (R(h)) of 0.19 μm while their aggregation causes formation of particles having R(h) in of approx. 0.5 μm and larger.
authors.affiliation: Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Kolman
authors.forename: Werner
authors.initials: W
authors.lastname: Steffen
authors.forename: Gabriela
authors.initials: G
authors.lastname: Bugla-Płoskońska
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Skwara
authors.forename: Jacek
authors.initials: J
authors.lastname: Pigłowski
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Butt
authors.forename: Adam
authors.initials: A
authors.lastname: Kiersnowski
mesh_terms: D000327:Adsorption; D000818:Animals; D001546:Bentonite / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry*; D002645:Chickens; D004527:Egg Proteins / Q000737:chemistry*; D004531:Eggs; D004591:Electrophoresis, Polyacrylamide Gel; D008027:Light; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles; D010316:Particle Size; D012996:Solutions; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D004527:Egg Proteins; D012996:Solutions; D001546:Bentonite