Abstract
The influence of temperature on the adsorption of PEGylated lysozyme and pure PEG on Toyopearl PPG-600M, a hydrophobic resin, is studied by batch equilibrium measurements and pulse response experiments. Differently PEGylated lysozymes are used for the studies, enabling a systematic variation of the solute properties. Either ammonium sulfate or sodium chloride are added. The enthalpy of adsorption is calculated from a van’t Hoff analysis based on these data. It is also directly measured by Isothermal Titration Calorimetry. In the investigated temperature range from 5°C to 35°C adsorption is favored by higher temperatures and hence endothermic. The results of the van’t Hoff analysis of the equilibrium and the pulse response data agree well. Discrepancies between enthalpies of adsorption obtained by calorimetry and van’t Hoff analysis are found and discussed. We conclude that the most likely explanation is that thermodynamic equilibrium is not reached in the experiments even though they were carried out carefully and in the generally accepted way.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.