Ultrasound Triggered Drug Release from Affinity-Based β-Cyclodextrin Polymers for Infection Control

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Ultrasound Technology

Background:

• Developing sustained drug delivery systems with on-demand capabilities is crucial for effective therapeutic interventions.
• Conventional drug delivery methods often lack precise control over release kinetics.
• Antibiotic resistance necessitates innovative strategies for localized and effective treatment.

Purpose of the Study:

• To investigate the use of pulsed therapeutic ultrasound (TUS) to trigger on-demand antibiotic release from β-cyclodextrin-polymer (pCD) implants.
• To evaluate the impact of TUS on the release rate of rifampicin (RIF) from pCD disks.
• To assess the therapeutic efficacy of TUS-enhanced RIF delivery against Staphylococcus aureus in vitro.

Main Methods:

• Fabrication of insoluble β-cyclodextrin-polymer (pCD) disks loaded with saturated rifampicin (RIF) solution.
• Application of pulsed therapeutic ultrasound (TUS) at 3 MHz and 1.8 W/cm² to stimulate drug release.
• Quantification of RIF release kinetics over time.
• In vitro assessment of bacterial eradication using a Staphylococcus aureus bioluminescence assay.

Main Results:

• Pulsed TUS significantly increased the short-term burst drug release rate by 100% within 4 days compared to controls.
• TUS stimulation led to a substantial reduction in bacterial load, with significantly lower CFU/mL observed at 1 and 24 hours.
• The combination of pCD disks, RIF, and TUS demonstrated enhanced antibacterial efficacy against Staphylococcus aureus.

Conclusions:

• Pulsed TUS is an effective noninvasive method to achieve on-demand antibiotic release from pCD implants.
• This technology holds promise for improving localized antibiotic delivery and combating bacterial infections.
• TUS offers a controllable mechanism to expedite drug release at desired intervals, potentially overcoming challenges in sustained drug delivery.