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Use of Microscale Thermophoresis to Measure Protein-Lipid Interactions
Published on: February 10, 2022
Thermodynamic parameters for salt-induced reversible protein precipitation from automated microscale experiments
Shahina S Ahmad1, Paul A Dalby
1Advanced Centre of Biochemical Engineering, Department of Biochemical Engineering, University College London, UK.
Biotechnology and Bioengineering
|September 28, 2010
Summary
This study introduces a high-throughput method using light scattering to measure protein precipitation thermodynamics. This technique aids in optimizing protein formulations and bioprocessing conditions by predicting precipitation behavior.
Area of Science:
- Biochemistry
- Biophysics
- Chemical Engineering
Background:
- Reversible protein precipitation is crucial for purification in bioprocessing and pharmaceuticals.
- Understanding precipitation conditions is key for developing stable protein formulations and preventing aggregation during chromatography.
Purpose of the Study:
- To develop a high-throughput method for determining thermodynamic parameters of protein precipitation using light scattering in microplates.
- To evaluate the potential for screening formulation additives and bioprocess conditions (e.g., pH) affecting protein precipitation.
- To complement existing microplate-based protein thermostability assays.
Main Methods:
- Utilized light scattering in microplates to measure protein precipitation.
- Employed hen egg-white lysozyme and alcohol dehydrogenase as model proteins.
- Varied ammonium sulfate and sodium chloride concentrations to determine precipitation extent.
- Applied global fitting of data to develop a predictive model for protein precipitation fraction.
- Determined thermodynamic parameters, including free energy of precipitation and average nucleus size.
Main Results:
- Established a high-throughput assay for quantifying reversible protein precipitation thermodynamics.
- Developed a predictive model for protein precipitation based on salt concentration and pH.
- Obtained thermodynamic parameters (free energy, nucleus size) for model proteins.
- Demonstrated the utility of the method for screening formulation additives and bioprocess conditions.
Conclusions:
- The light scattering microplate assay offers a rapid and efficient method for determining protein precipitation thermodynamics.
- This technique provides a powerful platform for protein formulation development and bioprocessing optimization.
- The generated data can validate theoretical models of reversible precipitation and molecular interactions.
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