Interferon alpha-2a interactions on glass vial surfaces measured by atomic force microscopy

Area of Science:

• Biophysics
• Materials Science
• Surface Chemistry

Background:

• Protein adsorption to container surfaces can impact drug efficacy and stability.
• Understanding protein-surface interactions is crucial for pharmaceutical development and storage.
• Borosilicate glass is commonly used for pharmaceutical packaging, but protein adsorption remains a concern.

Purpose of the Study:

• To investigate the adsorption and adhesion of interferon alpha-2a on different glass and mica surfaces.
• To evaluate the effectiveness of a specialized glass coating in preventing protein adsorption.
• To develop a force microscopy-based method for characterizing protein-glass interactions.

Main Methods:

• Atomic force microscopy (AFM) was employed for single-molecule imaging and force measurements.
• Protein adsorption was studied as a function of pH on mica surfaces.
• Adhesion forces between interferon alpha-2a and borosilicate glass vials were measured directly under aqueous buffer conditions.

Main Results:

• Interferon alpha-2a adsorption behavior varied with pH on mica surfaces.
• Adhesion forces on Schott FIOLAX Type I plus glass were 40% lower compared to standard Schott FIOLAX glass.
• The specialized "Type I plus" coating demonstrated superior performance in reducing protein adsorption.

Conclusions:

• The specialized "Type I plus" glass coating effectively minimizes unwanted interferon alpha-2a adsorption.
• AFM force measurements provide a valuable method for predicting and characterizing protein adsorption to glass container walls.
• These findings have implications for improving pharmaceutical storage and formulation stability.