Written in Water: Hydration Repulsion Governs Selective Protein Adsorption on Saccharide Self-Assembled Monolayers

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Bioinspired Design

Background:

• Saccharide-based materials are crucial for bioinspired design.
• Mechanisms of protein adsorption resistance and specific binding on these surfaces are not fully understood.

Purpose of the Study:

• To investigate the relationship between surface forces and protein adsorption on glucose, lactose, and maltose self-assembled monolayers.
• To elucidate the role of interfacial water in protein resistance and selective binding.

Main Methods:

• Systematic exploration of protein adsorption on glucose, lactose, and maltose self-assembled monolayers (SAMs).
• Utilized surface-sensitive techniques to analyze surface forces and interfacial water layers.
• Quantified protein adsorption using different proteins like bovine serum albumin (BSA), immunoglobulin G (IgG), and fibrinogen.

Main Results:

• Protein resistance followed the order: maltose > lactose > glucose.
• Protein adsorption varied, with BSA showing the least and fibrinogen the most adsorption, indicating saccharide-dependent selectivity.
• Repulsive forces were attributed to structured interfacial water layers, demonstrating a strong link between hydration repulsion and protein adsorption behavior.

Conclusions:

• Interfacial water acts as a dynamic barrier, preventing nonspecific protein binding.
• Saccharide structure influences interfacial water organization via hydrogen bonding, controlling adsorption resistance.
• Selective protein adsorption arises from the interplay between protein surface chemistry and interfacial hydration, providing design principles for biomaterials.