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THE "BOUND" WATER OF BIOLOGICAL COLLOIDS: A REPLY
1Division of Biochemistry, University of California Medical School, Berkeley.
The Journal of General Physiology
|October 30, 2009
Summary
Bull's objection to measuring bound water using ultrafiltration was invalid for glucose. Studies found no glucose adsorption by proteins like casein and gelatin, confirming the method's reliability for bound water estimation.
Area of Science:
- Biochemistry
- Physical Chemistry
Background:
- Estimating bound water in proteins is crucial for understanding their hydration.
- Previous methods faced objections regarding reference substance adsorption during ultrafiltration.
Purpose of the Study:
- To validate the ultrafiltration method for bound water estimation in proteins.
- To investigate the adsorption of glucose, a common reference substance, by proteins.
Main Methods:
- Ultrafiltration technique was employed.
- Glucose was used as the reference substance.
- Proteins such as casein and gelatin were utilized.
Main Results:
- The objection raised by Bull regarding glucose adsorption was found to be invalid.
- No detectable adsorption of glucose by casein and gelatin was observed.
- Calculated bound water values based on surface adsorption were minimal.
Conclusions:
- The ultrafiltration method is a valid approach for estimating bound water in proteins.
- Glucose is a suitable reference substance for this method, showing no significant adsorption.
- The bound water content in proteins, when estimated via surface adsorption, is quantitatively small.
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