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Blood Protein Exclusion from Polymer Brushes.
Eugenie Jumai'an1, Lechuan Zhang1, Michael A Bevan1
1Chemical & Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland21218, United States.
ACS Nano
|January 20, 2023
Summary
This study shows that poly(ethylene glycol) (PEG) brushes prevent protein adsorption, even at high concentrations. This indicates no protein corona formation, crucial for biomedical applications.
Area of Science:
- Biomaterials Science
- Surface Chemistry
- Biophysics
Background:
- Poly(ethylene glycol) (PEG) coatings are widely used to improve biocompatibility of materials.
- Understanding protein interactions with PEGylated surfaces is critical for preventing adverse biological responses.
Purpose of the Study:
- To investigate the interactions between adsorbed poly(ethylene glycol) (PEG) triblock copolymers and abundant blood proteins (serum albumin and immunoglobulin G) at physiological concentrations.
- To determine if protein coronas form on PEG brushes under these conditions.
Main Methods:
- Utilized Total Internal Reflection Microscopy to directly measure interaction potentials between adsorbed PEG copolymers and surfaces.
- Employed kT- and nanometer-scale resolution to analyze energy versus separation.
Main Results:
- In the absence of protein, adsorbed PEG copolymer repulsion matched theoretical predictions based on PEG brush dimensions.
- In the presence of proteins, concentration-dependent depletion attraction was observed, with no change in brush repulsion.
- These results indicate significant protein exclusion from the PEG brushes.
Conclusions:
- Protein coronas do not form on PEG brushes at physiological protein concentrations.
- PEG brushes effectively prevent protein adsorption, a key finding for designing biocompatible materials.
- The study presents a sensitive method for evaluating protein-surface interactions in biotechnology.
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