Nonfouling characteristics of dextran-containing surfaces

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Surface Chemistry

Background:

• Dextrans are versatile polysaccharides with numerous hydroxyl groups.
• Developing advanced materials with protein-repellent properties is crucial for biomedical applications.
• Controlling surface chemistry is key to tailoring material interactions with biological systems.

Purpose of the Study:

• To selectively oxidize hydroxyl groups in dextrans to aldehyde groups.
• To graft oxidized dextrans onto silicon surfaces.
• To investigate the impact of oxidation extent and molecular weight on protein adsorption and polymer conformation.

Main Methods:

• Selective oxidation of dextran hydroxyl groups using sodium periodate.
• Grafting of native and oxidized dextrans onto functionalized silicon surfaces.
• Analysis of protein adsorption and polymer conformation on modified surfaces.

Main Results:

• Controlled oxidation of dextrans yielded aldehyde groups with 6-100% conversion.
• Oxidized dextrans grafted onto silicon surfaces demonstrated significantly reduced protein adsorption.
• Negligible protein adsorption was observed when approximately 25% of hydroxyl groups were oxidized.
• Polymer conformation and protein resistance were strongly influenced by the balance of hydroxyl and aldehyde groups.

Conclusions:

• Oxidized dextrans exhibit excellent nonfouling properties, making them effective protein-resistant materials.
• The extent of hydroxyl group oxidation is a critical factor in achieving protein resistance.
• Oxidized dextrans represent a promising alternative to poly(ethylene glycol) for nonfouling applications.