关键词: 磁性纳米微球, 壳聚糖, 万古霉素, 乳化交联法, 磁靶向给药系统, 骨感染, 靶向治疗

Abstract:

BACKGROUND: Massive use of sensitive antibiotics is the basis of all treatment for bone infection. However, current therapies of local applied antibiotics are not satisfactory.
OBJECTIVE: To prepare vancomycin microspheres with a magnetic field compliance, to evaluate the physico-chemical characteristics of the prepared nanoparticles, and to observe antibacterial effect of vancomycin microspheres with magnetic field compliance in the rat model of bone infection.
METHODS: Chitosan served as the carrier of vancomycin. The vancomycin microspheres with magnetic field compliance were prepared by emulsion-chemical crosslink method. The shape of nanoparticles was observed by scanning electron microscope and transmission electron microscope, the magnetism was determined by vibrating sample magnetometer. The therapeutic efficacy to bone infection by the caudal vein injection of vancomycin microspheres with magnetic field compliance was investigated, as well as the histological and pathological changes in the tibia of rat model. The control group was treated with general use of vancomycin.
RESULTS AND CONCLUSION: The vancomycin microspheres with magnetic field compliance have been prepared successfully. The microspheres had regular spherical surfaces, at the mean diameter of 100–350 nm, the mean drug loading of 32.36%, and the mean encapsulation ratio of 80.9%, and with a good magnetic response in vitro. The vancomycin microspheres with magnetic field compliance could obviously elevate drug concentration in targeting zone and inhibit bone infection, the actual vancomycin dosage of the vancomycin microspheres group was 1/3 of general usage group. There was no significant difference in the therapeutic effect between vancomycin microspheres group and general usage group. The vancomycin microspheres with magnetic field compliance are a safe and reliable drug delivery targeting system, and expand the local application of antibiotics for bone infection treatment.