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Updated: May 12, 2026
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Composite Scaffolds of Interfacial Polyelectrolyte Fibers for Temporally Controlled Release of Biomolecules
Published on: August 19, 2015
Remotely triggered scaffolds for controlled release of pharmaceuticals
Paul Roach1, David J McGarvey, Martin R Lees
1Guy Hilton Research Centre, Institute of Science and Technology in Medicine, Keele University, Keele, ST4 7QB, UK. c.hoskins@keele.ac.uk.
International Journal of Molecular Sciences
|April 23, 2013
Summary
Smart scaffolds using iron oxide-gold hybrid nanoparticles (HNPs) enable remote drug delivery. Laser irradiation triggers localized heating, causing rapid scaffold shrinkage and drug release, demonstrating potential for advanced biomedical applications.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Drug Delivery Systems
Background:
- Fe3O4-Au hybrid nanoparticles (HNPs) show promise for image-guided, stimuli-responsive drug delivery.
- Integrating HNPs into thermo-responsive scaffolds offers advanced biomedical application potential.
Purpose of the Study:
- To fabricate smart scaffolds using thermo-responsive poly(N-isopropylacrylamide) (pNiPAM) and HNPs for remote, laser-triggered drug delivery.
- To evaluate the biological safety and efficacy of these pNiPAM-HNP composite scaffolds.
Main Methods:
- Synthesized gold-coated iron oxide nanoparticles (HNPs) via wet chemical precipitation and electrochemical coating.
- Functionalized HNPs with PEG to enhance stability and assessed cytotoxicity using live/dead staining and LDH assays on 7F2 cells.
- Fabricated pNiPAM-HNP composite scaffolds and investigated laser-triggered structural changes using a Q-switched Nd:YAG laser.
- Evaluated drug release using methylene blue as a model drug.
Main Results:
- PEG-coated HNPs exhibited no significant cytotoxic effects on 7F2 cells.
- pNiPAM-HNP scaffolds demonstrated rapid deformation within seconds upon laser irradiation due to internal heating.
- Methylene blue release was successfully achieved during the remote structural change of the scaffold.
Conclusions:
- Fe3O4-Au HNPs can be safely incorporated into pNiPAM scaffolds for biomedical applications.
- Laser-triggered heating of HNPs provides remote control over scaffold structure and drug release.
- These hybrid-scaffold constructs show significant potential for stimuli-responsive drug delivery systems.
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