pH-reversible, high-capacity binding of proteins on a substrate with nanostructure

Area of Science:

• Biomaterials Science
• Nanotechnology
• Surface Chemistry

Background:

• Developing controllable systems for protein adsorption and release is crucial for various biotechnological applications.
• Existing methods often face challenges with efficiency, reusability, and maintaining protein activity.

Purpose of the Study:

• To introduce a novel pH-switchable system for protein adsorption and release.
• To leverage the properties of poly(methacrylic acid) and nanostructured silicon nanowires for enhanced protein handling.

Main Methods:

• Modification of 3D nanostructured silicon nanowire arrays (SiNWAs) with poly(methacrylic acid) (poly(MAA)).
• Investigating the adsorption capacity of the modified material for lysozyme at different pH levels.
• Evaluating the release efficiency and enzyme activity of the adsorbed protein after pH change.

Main Results:

• The poly(MAA)-modified SiNWAs exhibited an approximately 80-fold increase in lysozyme binding capacity at pH 4 compared to smooth surfaces.
• Approximately 90% of the adsorbed lysozyme was successfully released by increasing the pH from 4 to 9.
• The released lysozyme retained its enzymatic activity after the adsorption-release cycle.

Conclusions:

• The developed poly(MAA)-modified SiNWAs offer a highly efficient and pH-controllable platform for protein adsorption and release.
• This system shows significant potential for applications in protein purification, drug delivery, and biosensing.
• The ability to release active proteins makes this material valuable for sensitive biological applications.