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High-throughput Identification of Bacteria Repellent Polymers for Medical Devices
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Evaluating antibiotic release profiles as a function of polymer coating formulation - biomed 2011
Sherry N Davidoff1, Justin O Sevy, Benjamin D Brooks
1University of Utah, Salt Lake City, Utah.
Biomedical Sciences Instrumentation
|April 29, 2011
Summary
Next-generation bone graft materials deliver antibiotics locally to prevent orthopedic implant infections. A novel polycaprolactone coating on bone allografts improves antibiotic release longevity, enhancing infection control.
Area of Science:
- Biomaterials Science
- Orthopedic Surgery
- Drug Delivery Systems
Background:
- Orthopedic implant surgeries face persistent infection rates (1-3%).
- Current antibiotic delivery methods are often short-lived, risking pathogen regrowth and resistance.
- Bone allografts are used to fill bone defects but lack inherent antimicrobial properties.
Purpose of the Study:
- To develop a sustained antibiotic delivery system using bone allografts.
- To improve the longevity of antibiotic release beyond current limitations.
- To create a next-generation bone graft filler with enhanced antimicrobial capabilities.
Main Methods:
- Bone allografts were coated with a polycaprolactone (PCL) polymer containing tobramycin.
- Coating techniques, including dipping, rapid drying, and incorporating water into the polymer formulation, were evaluated.
- Scanning electron microscopy (SEM) assessed coating uniformity.
- Antibiotic release kinetics were measured, and bioactivity was confirmed using bacteriostatic and bacteriocidal assays.
Main Results:
- Initial PCL coating attempts resulted in imperfect surfaces and suboptimal drug release.
- Incorporating water into the polymer formulation created a smoother, more uniform coating.
- The improved coating extended tobramycin release longevity to 5 weeks.
- Antibiotic bioactivity was confirmed between 2 and 4 weeks.
Conclusions:
- A water-modified PCL coating on bone allografts provides a promising strategy for sustained local antibiotic delivery.
- This approach can improve the duration of antibiotic release, potentially reducing orthopedic implant infection rates.
- The enhanced bone graft material offers a next-generation solution for combating orthopedic infections.
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