Reduction of irreversible protein adsorption on solid surfaces by protein engineering for increased stability

Area of Science:

• Biochemistry
• Materials Science
• Surface Chemistry

Background:

• Protein adsorption at interfaces is crucial for biomaterials and biosensors.
• Understanding factors influencing protein adsorption, like stability, is key to controlling surface interactions.
• Human carbonic anhydrase II variants were engineered to study stability effects.

Purpose of the Study:

• To investigate how protein stability affects adsorption and desorption kinetics and extent.
• To determine the relationship between protein stability and its conformational state upon adsorption.
• To explore protein engineering as a method to minimize irreversible protein adsorption.

Main Methods:

• Surface plasmon resonance (SPR) measurements were employed to analyze protein-surface interactions.
• Three human carbonic anhydrase II variants with varying stability but similar surface properties were utilized.
• Adsorption, desorption, and unfolding behaviors were assessed across diverse surfaces (charged and uncharged, hydrophilic and hydrophobic).

Main Results:

• Higher protein stability correlated positively with the adsorption rate and the maximum adsorbed protein amount.
• Increased protein stability led to greater elutability, indicating reduced irreversible adsorption.
• These correlations were explained by the denaturation rate and the conformational state of adsorbed proteins.

Conclusions:

• Protein stability is a critical determinant of adsorption behavior and surface interactions.
• Engineering proteins for enhanced stability can effectively reduce irreversible adsorption.
• This strategy holds promise for designing surfaces with controlled protein interactions.