Tunable protein-resistance of polycation-terminated polyelectrolyte multilayers

Area of Science:

• Materials Science
• Biotechnology
• Surface Chemistry

Background:

• Preventing nonspecific protein adsorption is vital for biomedical and biotechnological applications.
• Designing surfaces with optimal protein-resistance properties remains a significant challenge.

Purpose of the Study:

• To develop robust and versatile methods for creating protein-resistant surfaces.
• To investigate the protein-repelling capabilities of polycation-ending polyelectrolyte multilayers (PEM).

Main Methods:

• Fabrication of PEM films using weak polyelectrolytes: poly(allylamine hydrochloride) (PAH) and poly(acrylic acid) (PAA).
• Tuning protein adsorption by adjusting film buildup pH conditions.
• Characterization of film hydration and electrostatic interactions.

Main Results:

• Polycation-ending PEM films effectively prevented the adsorption of a model negatively charged protein, glucose oxidase (GOX).
• Protein resistance was attributed to high film hydration, overriding electrostatic interactions.
• Tunable protein adsorption was achieved by altering pH, suggesting control over internal film ionization.

Conclusions:

• Control over internal ionization in weak polyelectrolyte multilayers offers a simple method for tuning protein adsorption.
• These findings can guide the design of advanced biomaterials, biosensors, and protein separation devices.