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Published on: February 13, 2016
Development of smart delivery system for ascorbic acid using pH-responsive P(MAA-co-EGMA) hydrogel microparticles
Eunmi Lee1, Kyusik Kim, Moonjae Choi
1Department of Chemical Engineering, Hongik University, 72-1 Sangsu-dong, Mapo-gu, Seoul 121-791, Korea.
Drug Delivery
|July 15, 2010
Summary
pH-responsive hydrogel microparticles demonstrate intelligent delivery capabilities. These P(MAA-co-EGMA) particles exhibit controlled swelling and release of ascorbic acid, showing potential for enhanced drug delivery systems.
Area of Science:
- Materials Science
- Polymer Chemistry
- Biomedical Engineering
Background:
- Intelligent drug delivery systems require carriers that respond to physiological stimuli.
- Hydrogel microparticles offer potential for controlled release applications.
- pH-responsive materials are desirable for targeted delivery in different biological environments.
Purpose of the Study:
- To synthesize and characterize pH-responsive poly(methacrylic acid-co-ethylene glycol methacrylate) [P(MAA-co-EGMA)] hydrogel microparticles.
- To evaluate the feasibility of these microparticles as intelligent delivery carriers for ascorbic acid.
- To investigate the influence of pH on swelling, loading efficiency, and release kinetics of ascorbic acid.
Main Methods:
- Dispersion photopolymerization was employed to synthesize P(MAA-co-EGMA) hydrogel microparticles.
- Swelling behavior was analyzed across a range of pH values.
- Ascorbic acid loading efficiency and release profiles were determined.
- Skin permeability studies were conducted at different pH levels.
Main Results:
- A significant change in swelling ratio was observed around pH 5, with increased swelling at higher pH correlating with higher MAA content.
- Loading efficiency was primarily governed by hydrogel swelling, not electrostatic interactions.
- P(MAA-co-EGMA) microparticles exhibited pH-sensitive release of ascorbic acid, with higher skin permeability at pH 6 compared to pH 4.
- Ascorbic acid stability was maintained at high temperatures within the hydrogel particles.
Conclusions:
- P(MAA-co-EGMA) hydrogel microparticles are effective pH-responsive carriers.
- Their swelling and drug release characteristics can be tuned by MAA content and pH.
- These microparticles show promise for intelligent delivery of active compounds like ascorbic acid with enhanced stability and controlled release.
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