Controlled drug release from ultrasound-visualized elastic eccentric microcapsules using different resonant modes

Area of Science:

• Biomedical Engineering
• Materials Science
• Acoustic Drug Delivery

Background:

• Targeted drug delivery is crucial for enhancing therapeutic efficacy and minimizing side effects.
• Ultrasound technology offers non-invasive methods for controlling drug release and imaging.
• Elastic eccentric microcapsules (EEMs) present a novel platform for responsive drug delivery systems.

Purpose of the Study:

• To develop and evaluate a novel ultrasound-controlled drug delivery system.
• To investigate the use of elastic eccentric microcapsules (EEMs) for targeted and triggered drug release.
• To demonstrate the efficacy of ultrasound-guided drug release in vitro.

Main Methods:

• Fabrication of EEMs with varying inner cavity diameters using microfluidics.
• Visualization of EEMs using an ultrasound imaging system in a tissue phantom.
• Theoretical modeling to understand the effect of mode shapes (MSs) and resonant natural frequencies (NFs) on EEMs.
• Regulation of drug release (Rhodamine 6G) using low-frequency ultrasonic stimuli.
• In vitro assessment of doxorubicin hydrochloride (DOX) release and its effect on cancer cell viability.

Main Results:

• EEMs were successfully fabricated and visualized using ultrasound imaging.
• Theoretical modeling elucidated the relationship between MSs, NFs, and EEM resonant modes.
• Ultrasound stimuli effectively controlled the release rate of Rhodamine 6G from EEMs.
• Encapsulated doxorubicin hydrochloride demonstrated controlled release and reduced cancer cell viability in vitro.

Conclusions:

• The developed strategy enables ultrasound-guided visualization and triggered drug release.
• EEMs are a viable platform for developing advanced controlled drug delivery systems.
• This approach shows significant potential for targeted cancer therapy and other applications requiring precise drug administration.