Silk coating on poly(ε-caprolactone) microspheres for the delayed release of vancomycin

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Orthopaedic Surgery

Background:

• Osteomyelitis treatment is challenging, with controlled vancomycin release from microspheres showing promise.
• Large initial burst release from vancomycin-loaded poly(ε-caprolactone) (PCL) microspheres can hinder sustained therapeutic levels.
• Maintaining drug concentration above the minimum inhibitory concentration for extended periods is crucial for effective infection elimination.

Purpose of the Study:

• To explore silk fibroin (SF) as an aqueous coating for vancomycin-loaded PCL microspheres.
• To investigate the impact of SF coating on in vitro vancomycin release kinetics.
• To assess the potential of SF coating for improving drug delivery in osteomyelitis treatment.

Main Methods:

• Preparation and characterization of vancomycin-loaded PCL microspheres with and without SF coating.
• Analysis of particle size, vancomycin content, and material properties using FTIR and DSC.
• Scanning electron microscopy (SEM) for surface morphology evaluation.
• In vitro drug release studies to assess release profiles over time.

Main Results:

• Silk fibroin coating successfully reduced the initial burst release of vancomycin.
• SF coating significantly retarded the overall vancomycin release rate from PCL microspheres.
• Characterization confirmed the integrity and composition of the coated microspheres.

Conclusions:

• Silk fibroin serves as an effective aqueous coating material for vancomycin-loaded PCL microspheres.
• SF coating offers a viable strategy to prolong vancomycin release, addressing limitations of burst release.
• This approach holds potential for enhancing anti-infection effects in osteomyelitis management through sustained drug delivery.