Vancomycin release behaviour from amorphous calcium polyphosphate matrices intended for osteomyelitis treatment

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Materials Chemistry

Background:

• Antibiotic resistance necessitates advanced drug delivery systems.
• Calcium polyphosphate (CPP) matrices offer potential for localized antibiotic delivery.
• Controlling drug release kinetics is crucial for effective localized therapy.

Purpose of the Study:

• To develop and characterize novel calcium polyphosphate (CPP) antibiotic delivery matrices.
• To investigate the effect of a unique gelling and drying process on vancomycin release kinetics.
• To assess the stability of vancomycin activity and matrix degradation during elution.

Main Methods:

• Fabrication of antibiotic-loaded CPP pastes exposed to varying humidity (0, 5, 24 h) followed by drying.
• Monitoring vancomycin, Ca2+, and phosphate release over 130 h.
• Assessing vancomycin activity and using 31P-NMR to track phosphate chain length changes.

Main Results:

• The gelling and drying process significantly delayed initial vancomycin release (2-4 h) and extended the release period by 80 h.
• Vancomycin activity remained intact, and the matrix underwent swelling and erosion.
• Phosphate chain degradation was observed, with no strong correlation between matrix erosion and drug release.

Conclusions:

• The developed CPP matrices effectively delay antibiotic release, prolonging therapeutic presence.
• The fabrication method preserves antibiotic activity and offers a promising approach for localized drug delivery.
• Further research is warranted to explore the full potential of these CPP matrices in drug delivery applications.