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Ensemble Force Spectroscopy by Shear Forces
Published on: July 26, 2022
Effects of shear on proteins in solution
1School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK. c.r.thomas@bham.ac.uk
Biotechnology Letters
|November 19, 2010
Summary
Shear forces alone rarely damage proteins in solution. Instead, damage often results from interfacial phenomena, such as moving gas-liquid interfaces or nanoparticles, impacting therapeutic protein quality and patient safety.
Area of Science:
- Biochemistry
- Protein Chemistry
- Fluid Mechanics
Background:
- Decades of research have investigated protein denaturation by shear during processing.
- Recent concerns focus on the impact of shear and related effects on therapeutic protein quality.
Purpose of the Study:
- To clarify the mechanisms of protein damage in solution during processing.
- To differentiate between true shear effects and interfacial phenomena.
Main Methods:
- Review of historical and recent research on protein behavior under mechanical stress.
- Analysis of fluid mechanical shear versus interfacial phenomena.
Main Results:
- Fluid mechanical shear alone is unlikely to damage most proteins.
- Moving gas-liquid interfaces are particularly detrimental to protein stability.
- Protein aggregation on nanoparticles from solid surfaces is a significant safety concern.
Conclusions:
- Labeling all protein damage as "shear" is inaccurate and hinders understanding.
- Interfacial phenomena, not shear itself, are the primary drivers of protein damage in many processing scenarios.
- Accurate identification of damage mechanisms is crucial for ensuring therapeutic protein quality and patient safety.
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