Login

Journal Image
Current Drug Delivery
ISSN (Print): 1567-2018
ISSN (Online): 1875-5704
Epub Full Text Article
DOI: 10.2174/1567201811666140616160948









Temporal Separation in the Release of Bioactive Molecules from a Moldable Calcium Sulfate Bone Graft Substitute

img
Author(s): Matt E. Brown, Yuan Zou, R. Peyyala, Thomas D. Dziubla and David A. Puleo
Abstract:
Treatment of infected bone defects presents a considerable challenge due to the complications that occur from significant bone damage concomitant with contaminated tissue. These wounds are most often treated in a two-step sequence, where the infection is first eliminated before any attempt to repair the bone is undertaken. In order to combine these two treatment steps into one procedure, a moldable bone grafting material was developed to deliver drugs in a temporally separated manner. This was accomplished by a two-layered calcium sulfate composite consisting of a moldable outer shell containing antibiotic-loaded poly(lactic-co-glycolic acid) microspheres wrapped around a preformed core containing an osteogenic drug. The release of vancomycin from the shell portion began immediately and continued over the course of 6 weeks, while the release of simv astatin from the core was delayed for 12 days before being released over the next 4 weeks. Bioactivity of vancomycin was shown in modified Kirby-Bauer experiments in which whole samples inhibited Staphylococcus aureus ( S. aureus) growth for 2 weeks. This two-layered system is capable of delivering antibiotics locally for clinically relevant periods of time and delaying the release of osteogenic drugs to mimic a two-step procedure that has potential for treating infected bone defects
Keywords:
Bone filler, bone graft substitute, calcium sulfate, composite, moldable, sequential release, simvastatin, vancomycin
Affiliation:
522A Robotics and Manufacturing Building Department of Biomedical Engineering University of Kentucky Lexington, KY 40506-0108 USA