Formulation and Characterization of Bone-Targeting Vancomycin-Loaded Liposomes

Area of Science:

• Biomedical Engineering
• Drug Delivery Systems
• Nanotechnology

Background:

• Osteomyelitis and bone infections require effective antibiotic delivery.
• Liposomal carriers offer potential for targeted drug delivery.
• Vancomycin is a critical antibiotic for treating Gram-positive bacterial infections.

Purpose of the Study:

• To formulate and characterize bone-targeting vancomycin-loaded liposomes.
• To enhance the delivery of vancomycin to bone tissue.
• To evaluate the bone affinity of the developed liposomal carrier.

Main Methods:

• Liposomes were formulated using DSPC, cholesterol, and DCP.
• Vancomycin was encapsulated using dehydration-rehydration and thin-film hydration methods.
• Sodium alendronate was conjugated to DSPE-PEG-COOH to create a bone-targeting moiety.

Main Results:

• Successful conjugation of alendronate to liposome surface confirmed by IR spectroscopy.
• In vitro studies showed preferential binding of targeted liposomes to hydroxyapatite.
• Ex vivo studies demonstrated enhanced binding of targeted liposomes to mouse tibial bone tissue.

Conclusions:

• Surface-modified vancomycin-loaded liposomes exhibit significantly enhanced bone affinity.
• This formulation holds great potential for targeted antibiotic delivery to infected bones.
• The developed liposomal carrier represents a promising strategy for treating bone infections.