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ULTRAFILTRATION : II. "BOUND" WATER (HYDRATION) OF BIOLOGICAL COLLOIDS
1Division of Biochemistry, University of California Medical School, Berkeley.
The Journal of General Physiology
|October 30, 2009
Summary
This study investigated "bound" water in colloid solutions. Findings show only a small fraction of water loses solvent properties when associated with colloids like gelatin and starch.
Area of Science:
- Colloid science
- Biophysical chemistry
- Solution chemistry
Background:
- Water's role in biological systems is crucial.
- Understanding the state of water in colloid solutions is key to comprehending their properties.
- The concept of "bound" water, which lacks solvent properties, is debated.
Purpose of the Study:
- To quantify the fraction of water that loses solvent properties in various colloid solutions.
- To investigate the association of water with macromolecules like proteins and carbohydrates.
- To determine if "bound" water exists in significant amounts in biological fluids.
Main Methods:
- Utilized an ultrafiltration technique to separate water fractions.
- Analyzed solutions of gelatin, casein, starch, and glycogen.
- Examined human blood serum.
Main Results:
- Demonstrated that only a minimal fraction of water exhibits "bound" characteristics.
- Observed limited water association with gelatin, casein, starch, and glycogen.
- Found negligible "bound" water in blood serum.
Conclusions:
- The majority of water in these colloid solutions retains its solvent properties.
- "Bound" water, as defined by loss of solvent properties, is not prevalent in these systems.
- This challenges assumptions about extensive water immobilization around colloids.
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