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Updated: Jan 21, 2026
06:02
Multi-timescale Microscopy Methods for the Characterization of Fluorescently-labeled Microbubbles for Ultrasound-Triggered Drug Release
Published on: June 12, 2021
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Ultrasound-triggered release from metal shell microcapsules.
Alison L White1, Christian Langton2, Marie-Luise Wille2
1Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Queensland 4072, Australia; CSIRO Probing Biosystems Future Science Platform, Brisbane, Australia; ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, St. Lucia 4072, Australia.
Journal of Colloid and Interface Science
|July 21, 2019
Summary
Gold shell microcapsules show promise for controlled drug delivery. Focused ultrasound (FUS) can trigger the rupture of these microcapsules, enabling sustained dye release for potential implantable drug delivery systems.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Drug Delivery Systems
Background:
- Metal shell microcapsules offer superior core retention compared to polymer shells for drug delivery.
- Focused ultrasound (FUS) is a potential trigger for drug release from microcapsules.
Purpose of the Study:
- To investigate the response of gold shell microcapsules, with and without inner polymer shells, to focused ultrasound (FUS) and standard ultrasound.
- To evaluate the potential of these microcapsules as implantable drug delivery vehicles.
Main Methods:
- Exploration of gold shell microcapsule response to standard and focused ultrasound.
- Correlation analysis of gold shell thickness and rupture extent.
- Assessment of microcapsule rupture efficiency in hydrogel matrices versus aqueous media.
Main Results:
- Gold shell microcapsules with inner polymer shells rupture under standard ultrasound, with rupture extent linearly correlated to gold shell thickness.
- Low FUS power (0.16 W) can rupture 53 nm gold shell microcapsules.
- Gold shell microcapsules without polymer shells rupture more efficiently in hydrogel matrices with FUS.
- Thicker gold shells enhance ultrasound-triggered rupture irrespective of the surrounding medium.
- Dye release from ruptured capsules was sustained for 7-35 days.
Conclusions:
- Emulsion-templated gold shell microcapsules in hydrogel matrices are suitable for implantable drug delivery.
- Focused ultrasound provides external control for triggering drug release from these systems.
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