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Alternating Magnetic Field-Responsive Hybrid Gelatin Microgels for Controlled Drug Release
Published on: February 13, 2016
A magnetically triggered composite membrane for on-demand drug delivery
Todd Hoare1, Jesus Santamaria, Gerardo F Goya
1Department of Chemical Engineering, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4L7, Canada.
Nano Letters
|September 10, 2009
Summary
New nanocomposite membranes with thermosensitive nanogels and magnetite nanoparticles enable on-demand drug delivery. These biocompatible, noncytotoxic membranes show controlled release triggered by magnetic fields, even after implantation.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Drug Delivery Systems
Background:
- Thermosensitive polymers offer potential for controlled release applications.
- Magnetite nanoparticles can be remotely actuated by magnetic fields.
- Developing 'on-demand' drug delivery systems remains a significant challenge.
Purpose of the Study:
- To design and evaluate nanocomposite membranes for magnetically triggered drug delivery.
- To investigate the release kinetics of sodium fluorescein from the membranes.
- To assess the biocompatibility and in vivo stability of the developed membranes.
Main Methods:
- Fabrication of nanocomposite membranes using poly(N-isopropylacrylamide)-based nanogels and magnetite nanoparticles.
- Utilizing an oscillating magnetic field to actuate the membranes for drug release.
- Quantifying sodium fluorescein release over multiple magnetic cycles.
- Evaluating membrane performance and biocompatibility after subcutaneous implantation.
Main Results:
- Successful demonstration of on-off release of sodium fluorescein over multiple magnetic cycles.
- Drug delivery dose was directly proportional to the duration of the magnetic field 'on' pulse.
- Developed membranes exhibited noncytotoxic and biocompatible properties.
- Switchable flux properties were retained after 45 days of subcutaneous implantation.
Conclusions:
- Nanocomposite membranes offer a promising platform for on-demand drug delivery.
- Magnetic field actuation provides effective control over drug release kinetics.
- The membranes demonstrate excellent biocompatibility and long-term stability in vivo.
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