Antibiotic-loaded plaster of Paris implants coated with poly lactide-co-glycolide as a controlled release delivery system for the treatment of bone infections.
Plaster of Paris implants containing vancomycin (60 mg/g of carrier) were prepared in order to be used as local delivery system for the treatment of bone infections. The regulation of the release rate was performed by coating the carrier with a polylactide-co-glycolide polymer composed by 10% (w/w) polyglycolic acid and 90% (w/w) racemic poly (D,L-lactic acid). The release of the antibiotic from the biodegradable matrix was evaluated in vitro. From this investigation, it is clear that the drug elution depends on the coating depth. After a burst effect occurring on the first day of the experiment, therapeutic concentrations were measured during one week when uncoated implants were used. The coating allowed decrease of the burst effect and extended efficient release to more than five weeks when the implants were embedded with six layers (162 microns) of PLA45GA10. This delivery system was implanted into the femoral condyle of rabbits. It was shown that the in vivo release was also closely regulated by the coating depth. In all bone tissues (bone marrow and cortical bone) surrounding the pellets, the drug concentration exceeded the Minimum Inhibitory Concentration for the common causative organisms of bone infections (Staphylococcus aureus) for at least four weeks without inducing serum toxic levels. Due to its cheapness, facility of use and sterilization, biocompatibility and biodegradability, plaster of Paris coated with PLA45GA10 polymer giving a controlled release of vancomycin appears to be a promising sustained release delivery system of antibiotics for the treatment of bone and joint infections.
Benoit
M A
MA
Louvain Catholic University, Brussels, Belgium.
Mousset
B
B
Delloye
C
C
Bouillet
R
R
Gillard
J
J
D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D001672:Biocompatible Materials; D001673:Biodegradation, Environmental; D002133:Calcium Sulfate; D003692:Delayed-Action Preparations / Q000008:administration & dosage*; D004195:Disease Models, Animal; D016503:Drug Delivery Systems / Q000379:methods*; D004343:Drug Implants; D005269:Femur / Q000000981:diagnostic imaging / Q000187:drug effects; D016231:Fluorescence Polarization Immunoassay; D019344:Lactic Acid; D008422:Materials Testing; D010019:Osteomyelitis / Q000000981:diagnostic imaging / Q000188:drug therapy*; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D011817:Rabbits; D011859:Radiography; D013203:Staphylococcal Infections / Q000188:drug therapy*; D014640:Vancomycin / Q000008:administration & dosage* / Q000493:pharmacokinetics
D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D004343:Drug Implants; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D014640:Vancomycin; D002133:Calcium Sulfate