EFFECT OF ANTIBIOTIC VETORIZED WITH MAGNETIC NANOPARTICLES FOR TREATMENT OF INFECTION BY Staphylococcus aureus MULTI RESISTANT
Magnetic Field Therapy. Magnetite Nanoparticles. Methicillin-Resistant Staphylococcus aureus. Rats.
Objective: To evaluate the effect of oxacillin bound to magnetic nanoparticles on the model of local infection in rats.
METHODS: Twelve Wistar rats weighing 290 ± 18g were randomly divided into four groups (n = 6, each) and all rats had a magnetic ring sutured to the right thighs. In the bioavailable distribution group, 0.1mL of 99mTc-magnetite (0.66 MBq) was injected i.v and after 30 minutes, the biodistribution of 99mTc-magnetite was evaluated in the right and left thighs. The other groups were inoculated with MRSA on each thigh muscle. The rats of group 1 were injected i.v. with magnetite, group 2 with magnetite-Oxacillin, group 3 with saline, all administered twice daily. After 24 hours, muscle secretion samples were collected for microbiological analysis; muscles, lungs and kidneys for histology.
Results: The uptake of 99mTc-magnetite was three times greater in the muscles of the right thigh (with external magnet) than in the left. In the groups administered magnetite and magnetite-Oxacillin, the samples collected in the thigh muscles, the amount of colony forming units (CFU) of the bacterium was significantly lower than in the saline controls. The inflammatory reaction in muscles and lungs was significantly lower in rats receiving magnetite-Oxacillin than in the other groups (p <0.001).
Conclusion: This study confirms the potential antimicrobial activity of magnetic nanoparticles for methicillin resistant strains of S. aureus, which in addition to concentrating the antibiotic at the site of infection, positively influenced the treatment.