Polymeric microbubbles as delivery vehicles for sensitizers in sonodynamic therapy

Area of Science:

• Biomaterials Science
• Nanomedicine
• Oncology

Background:

• Microbubbles (MBs) are emerging as drug delivery vehicles for sonodynamic therapy (SDT).
• Attaching sensitizer drugs to lipid MBs reduces their stability.
• Polymer MBs offer a potential solution for improved stability in SDT.

Purpose of the Study:

• To compare the stability and efficacy of lipid versus polymer (PLGA) microbubbles for delivering rose bengal in sonodynamic therapy.
• To evaluate the potential of PLGA microbubbles as a more stable alternative for targeted cancer treatment.

Main Methods:

• Preparation of lipid and poly(lactic-co-glycolic acid) (PLGA) microbubbles conjugated with rose bengal.
• Assessment of microbubble stability and selective destruction using ultrasound.
• In vivo efficacy study using ectopic human BxPC-3 tumors in mice, comparing PLGA-MB conjugates with and without ultrasound treatment.

Main Results:

• PLGA microbubble conjugates demonstrated significantly greater stability compared to lipid microbubble conjugates.
• Ultrasound treatment effectively destroyed PLGA microbubbles at therapeutic intensities without compromising stability.
• Mice treated with PLGA MB-rose bengal conjugate and ultrasound showed a 34% reduction in tumor volume, while conjugate-only treatment led to a 48% increase.

Conclusions:

• Poly(lactic-co-glycolic acid) (PLGA) microbubbles provide a more stable platform for sensitizer drug delivery in sonodynamic therapy compared to lipid microbubbles.
• PLGA microbubbles maintain their stability and therapeutic potential, offering a promising alternative for targeted cancer treatment via SDT.