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Published on: June 12, 2021
Pulsed in vitro release and in vivo behavior of exploding microcapsules
Bruno G De Geest1, Stefaan De Koker, Jo Demeester
1Department of Pharmaceutics, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands. br.degeest@ugent.be
Summary
Researchers developed self-exploding microcapsules for pulsed drug delivery. These biodegradable capsules release contents after an incubation period, offering a potential alternative to multiple injections for vaccines and therapeutics.
Area of Science:
- Biomaterials Science
- Drug Delivery Systems
- Nanotechnology
Background:
- Multiple injections are often required for vaccines to achieve sufficient immunity.
- Pulsatile drug delivery systems can improve therapeutic efficacy and patient compliance.
- Existing systems may lack precise control over drug release timing.
Purpose of the Study:
- To develop and characterize self-exploding microcapsules for pulsed drug delivery.
- To investigate the factors influencing the release kinetics of these microcapsules.
- To evaluate the in vivo biocompatibility of the microcapsule system.
Main Methods:
- Fabrication of microcapsules with a biodegradable microgel core and a biopolyelectrolyte membrane.
- Tuning of microgel cross-link density to control degradation and swelling pressure.
- Encapsulation and release studies using 50 nm latex nanoparticles as a model cargo.
- In vivo biocompatibility assessment via subcutaneous injection in mice.
Main Results:
- Demonstrated pulsed release of encapsulated cargo after a defined incubation time under physiological conditions.
- Showcased that microcapsule explosion time and release profile can be modulated by altering microgel cross-link density.
- Confirmed the biocompatibility of the self-exploding microcapsules following subcutaneous administration in mice.
Conclusions:
- Self-exploding microcapsules offer a promising platform for controlled, pulsatile drug delivery.
- The system's release characteristics are tunable by adjusting the core material's properties.
- The demonstrated biocompatibility supports potential in vivo applications, such as vaccine delivery.
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