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Updated: Jul 9, 2026
06:10
Encapsulated Cell Technology for the Delivery of Biologics to the Mouse Eye
Published on: March 30, 2020
[Polyelectrolyte microcapsules as systems for delivery of biologically active substances]
Biomeditsinskaia Khimiia
|December 15, 2007
Summary
New biodegradable microcapsules were developed using layer-by-layer adsorption for targeted delivery of biologically active substances (BAS). These microcapsules effectively protected and released enzymes, maintaining their bioactivity for potential therapeutic applications.
Area of Science:
- Biomaterials Science
- Drug Delivery Systems
- Nanotechnology
Background:
- Developing effective delivery systems for biologically active substances (BAS) is crucial for therapeutic applications.
- Biodegradable and biocompatible materials are sought after for safe in vivo use.
- Microcapsules offer a promising platform for encapsulating and protecting sensitive biomolecules.
Purpose of the Study:
- To fabricate novel biodegradable microcapsules for the controlled delivery of biologically active substances (BAS).
- To investigate the immobilization and bioactivity retention of enzymes within these microcapsules.
- To assess the stability and triggered release properties of the developed microcapsule system.
Main Methods:
- Utilized layer-by-layer (LbL) adsorption of sodium alginate (Alg) and poly-L-lysine (PLL) onto CaCO3 microparticle templates.
- Fabricated core-shell structures and subsequently generated hollow microcapsules via core dissolution with EDTA.
- Entrapped chymotrypsin (Chym) as a model enzyme to evaluate encapsulation efficiency and retained activity.
Main Results:
- Successfully prepared hollow biodegradable microcapsules with entrapped chymotrypsin (Chym).
- The immobilized enzyme retained approximately 86% of its original activity.
- Microcapsules demonstrated stability in acidic conditions and triggered release in a slightly alkaline medium via trypsin treatment.
- Released Chym remained active, confirming the integrity of the biomolecule post-release.
Conclusions:
- The LbL-fabricated microcapsules are a viable system for delivering biologically active substances (BAS) while preserving their bioactivity.
- The tunable degradation profile allows for controlled release, suitable for targeted delivery in human and animal applications.
- These microcapsules represent a novel platform for developing advanced drug and enzyme delivery systems.
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