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Injectable Supramolecular Polymer-Nanoparticle Hydrogels for Cell and Drug Delivery Applications
Published on: February 7, 2021
Surface chemistry at the nanometer scale influences insulin aggregation
Lalit M Pandey1, Simon Le Denmat, Didier Delabouglise
1Laboratoire des Matériaux et du Génie Physique (LMGP), Grenoble Institute of Technology, Grenoble, France. lalit_be@yahoo.co.in
Colloids and Surfaces. B, Biointerfaces
|July 7, 2012
Summary
Surface properties like hydrophobicity and roughness control insulin aggregation. Varying surface chemistry affects lag time and protein adsorption, influencing aggregate formation and structure.
Area of Science:
- Biomaterials Science
- Surface Chemistry
- Protein Aggregation Studies
Background:
- Protein aggregation is implicated in various diseases.
- Controlling protein aggregation on surfaces is crucial for biomedical applications.
- Surface properties significantly influence protein behavior.
Purpose of the Study:
- To investigate how surface chemistry and roughness affect insulin aggregation kinetics.
- To determine the role of surface composition in protein adsorption and aggregation.
- To understand the influence of surface topography on aggregate morphology and structure.
Main Methods:
- Synthesis of surfaces with tunable hydrophobicity and roughness using mixed self-assembled monolayers (SAMs) of amine and octyl silanes.
- Characterization of insulin aggregation kinetics, including lag phase and growth rate, on these engineered surfaces.
- Quantification of protein adsorption and adsorption rates during the aggregation process.
Main Results:
- Lag time of insulin aggregation varied with the amine fraction on the surface, while the growth rate did not.
- Protein adsorption and adsorption rates were maximal for surfaces with equal amine and octyl fractions.
- Initial surface roughness influenced the rate of protein adsorption and the time to form aggregation nuclei.
- Surface chemistry and topography affected the morphology and secondary structure of adsorbed and released insulin aggregates.
Conclusions:
- Surface properties, specifically hydrophobicity and roughness, are critical determinants of insulin aggregation.
- Tailoring surface chemistry and topography can modulate protein adsorption and aggregation kinetics.
- Understanding these surface-protein interactions is key to designing materials for controlling protein aggregation in biomedical contexts.
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