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Published on: January 15, 2015
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pH-responsive drug delivery system based on hollow silicon dioxide micropillars coated with polyelectrolyte
María Alba1, Pilar Formentín1, Josep Ferré-Borrull1
1Departament d'Enginyeria Electrònica, Elèctrica i Automàtica, Universitat Rovira i Virgili, Avda. Països Catalans 26, Tarragona 43007, Spain.
Nanoscale Research Letters
|September 16, 2014
Summary
Researchers developed pH-responsive hollow silicon dioxide micropillars for targeted drug delivery. These novel systems demonstrate controlled release of doxorubicin, showing higher release rates at lower pH levels, indicating potential for localized therapies.
Area of Science:
- Materials Science
- Nanotechnology
- Biomedical Engineering
Background:
- Macroporous silicon dioxide micropillars offer hollow cores for drug loading.
- Polyelectrolyte multilayers (PEM) can be assembled via layer-by-layer (LbL) technique.
- PEM coatings can impart stimuli-responsive properties to nanomaterials.
Purpose of the Study:
- To fabricate and characterize pH-responsive polyelectrolyte multilayer-coated hollow silicon dioxide micropillars.
- To investigate the drug loading and release capabilities of these systems.
- To evaluate the potential of these hybrid composites as localized drug delivery systems.
Main Methods:
- Fabrication of hollow silicon dioxide micropillars using electrochemical etching of macroporous silicon.
- Assembly of polyelectrolyte multilayers using the layer-by-layer technique with poly(allylamine hydrochloride) and sodium poly(styrene sulfonate).
- Loading and in vitro release studies of doxorubicin at different pH values (5.2 and 7.4).
Main Results:
- The fabricated micropillars demonstrated pH-responsive behavior for drug delivery.
- A higher release rate of doxorubicin was observed at pH 5.2 compared to pH 7.4.
- The number of polyelectrolyte bilayers influenced drug loading and release kinetics.
Conclusions:
- Polyelectrolyte multilayer-coated hollow silicon dioxide micropillars are effective pH-responsive drug delivery systems.
- These systems show potential for controlled and localized release of positively charged drugs like doxorubicin.
- The tunable nature of PEM coatings offers a platform for developing advanced drug delivery technologies.
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