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Updated: Jun 26, 2026
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Preparation and Characterization of SDF-1α-Chitosan-Dextran Sulfate Nanoparticles
Published on: January 22, 2015
Dynamic rejection of colloidal particles with generating dextran by enzymatic reaction
Hidetaka Kawakita1, Yuko Yoshimura, Kohshi Hamamoto
1Department of Applied Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan. kawakita@cc.saga-u.ac.jp
Summary
Dextransucrase enzyme immobilized on inorganic membranes dynamically rejects colloidal particles. The enzyme generates dextran, which occupies membrane pores, enhancing particle rejection efficiency.
Area of Science:
- Biocatalysis
- Membrane Science
- Colloid Science
Background:
- Enzymatic reactions can be harnessed for separation processes.
- Immobilized enzymes offer advantages in continuous flow systems.
- Dextran, a polysaccharide, can alter membrane properties.
Purpose of the Study:
- To investigate the dynamic rejection of colloidal particles using immobilized dextransucrase.
- To evaluate the effect of in-situ dextran generation on membrane performance.
- To understand the mechanism of enhanced particle rejection.
Main Methods:
- Immobilization of dextransucrase onto inorganic porous membranes.
- Enzymatic reaction of sucrose to generate dextran within the membrane.
- Permeation of colloidal particle solutions through the functionalized membranes.
- Monitoring of particle rejection percentages over time.
Main Results:
- Immobilized dextransucrase membranes showed constant rejection for 55 and 100 nm particles.
- Permeating sucrose solutions with colloidal particles led to a dynamic increase in rejection.
- Dextran generation within the membrane pores was responsible for the enhanced rejection.
- The steric volume of generated dextran progressively occupied membrane pores.
Conclusions:
- Immobilized dextransucrase provides a dynamic method for colloidal particle separation.
- In-situ dextran generation offers a tunable mechanism to enhance membrane filtration.
- This approach demonstrates potential for advanced separation technologies in various fields.
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