title: Interferon alpha-2a interactions on glass vial surfaces measured by atomic force microscopy.
abstract: Atomic force microscopy was used to study adsorption and adhesion peculiarities of interferon alpha-2a on glass and mica surfaces. The specific protein adsorption behavior as a function of the pH value was illustrated on mica by single molecule imaging, while adhesion forces between interferon molecules and inner surfaces of borosilicate glass vials were measured directly under aqueous buffer conditions by force microscopy. We found that the adhesion force on Schott FIOLAX Type I plus was reduced by 40% of the total adhesion force measured on Schott FIOLAX, a standard type I borosilicate glass quality. These results reflect the anticipated superiority of the special "Type I plus" coating over undesired protein adsorption to glass. In addition, this study gives insight into a new method to predict unintended protein adsorption to glass container walls and to characterize the adsorption process by force measurement.
authors.affiliation: Institute of Physics, University of Basel, F. Hoffmann-La Roche AG, Basel. monica.schwarzenbach@mepha.ch
authors.forename: Monica S
authors.initials: MS
authors.lastname: Schwarzenbach
authors.forename: Peter
authors.initials: P
authors.lastname: Reimann
authors.forename: Verena
authors.initials: V
authors.lastname: Thommen
authors.forename: Martin
authors.initials: M
authors.lastname: Hegner
authors.forename: Marco
authors.initials: M
authors.lastname: Mumenthaler
authors.forename: Jacky
authors.initials: J
authors.lastname: Schwob
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Güntherodt
mesh_terms: D000327:Adsorption; D000538:Aluminum Silicates / Q000737:chemistry; D005898:Glass / Q000737:chemistry*; D066298:In Vitro Techniques; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D011994:Recombinant Proteins; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties; D013678:Technology, Pharmaceutical
chemical_list: D000538:Aluminum Silicates; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D012822:Silicon Dioxide; C011934:mica