Comparing the enhancement efficiency between liposomes and microbubbles for insulin pulmonary absorption

Area of Science:

• Biomedical Engineering
• Drug Delivery Systems
• Pulmonary Medicine

Background:

• Investigating novel methods for enhancing pulmonary drug absorption is crucial for effective protein-based therapies.
• Liposomes and microbubbles are explored as potential carriers for intrapulmonary delivery.

Purpose of the Study:

• To compare the efficiency of liposomes and microbubbles in enhancing insulin pulmonary absorption.
• To evaluate the safety and efficacy of these delivery systems in vivo.

Main Methods:

• Liposomes and microbubbles were prepared and characterized for size distribution.
• In vitro cytotoxicity was assessed using the MTT assay in A549 cells.
• Cellular uptake and in vivo pulmonary absorption in Sprague-Dawley rats were evaluated.

Main Results:

• Both formulations exhibited monodispersed size distributions; microbubbles (1.0 μm) were smaller than liposomes (3.1 μm).
• A safe dosage range for phospholipid-based vesicles was determined to be <25% (vol/vol).
• Insulin-microbubble mixtures showed significantly higher cellular uptake and greater blood glucose reduction (60.8%) with improved bioavailability (48.6%) compared to insulin-liposomes (35.0% reduction, 30.8% bioavailability).

Conclusions:

• Microbubbles demonstrate superior efficiency over liposomes for insulin pulmonary absorption.
• Microbubbles represent a promising strategy for enhancing intrapulmonary delivery of protein therapeutics.