Using 3-D dense packing models to predict surface tension change due to protein adsorption

Area of Science:

• Biophysics
• Surface Chemistry
• Biomaterials Science

Background:

• Traditional protein adsorption models emphasize protein constituent differences.
• Experimental data indicate similarities in human blood-borne protein adsorption despite size and functional variations.
• A hard-sphere model suggests solvent dominance in protein adsorption processes.

Purpose of the Study:

• To independently evaluate the efficacy of the hard-sphere protein adsorption model.
• To adapt the model to depend on molecular volume instead of molecular weight.
• To explore the impact of adsorption-induced conformational changes on model accuracy.

Main Methods:

• Independent evaluation of a hard-sphere protein adsorption model.
• Model adjustment to incorporate molecular volume dependence.
• Analysis of adsorption-induced conformational changes (volume invariant vs. volume changing).

Main Results:

• The hard-sphere model, adjusted for molecular volume, accurately represents protein adsorption.
• Volume-invariant conformational changes are well-modeled, while volume-changing ones are not.
• The model successfully captures adsorption differences for BSA (multi-layer) and HSA (monolayer), and non-spherical molecules like fibrinogen.

Conclusions:

• The solvent plays a dominant role in protein adsorption.
• Molecular volume is a critical factor influencing surface tension changes during adsorption.
• The refined hard-sphere model demonstrates general applicability for predicting protein adsorption behavior.