For magnetic induction hyperthermia cancer micron cobalt base alloy microsphere injection
|Beijing University of Traditional Chinese Medicine
|Microbial and Biochemical Pharmacy
|Magnetic Induction Cobalt Alloys Hyperthermia Tumor Injection
ObjectiveThe aim of this study was to find out novel kinds of micro-scale magnetic materials for tumor magnetic hyperthermia.Methods1Screening and Characterization of micron media:9alloy powders purchased from different manufacturers and models were measured temperature performance under alternating magnetic field. Co42A microspheres were selected for subsequent experiments. The shape of Co42A microspheres were observed using scanning electron microscopy. The particles size was determined by using laser particle size analyzer. The saturation magnetic was tested by using vibrating sample magnetometer. The heat-generating ability was tested under an alternating magnetic field.2Syringeability of Co42A microspheres: Co42A microspheres were dispersed in different media. The sodium hyaluronate gel was chosen as the suspending agent to suspend Co42A microspheres. Temperature curves were recorded for Co42A microspheres suspended in gel or injected in the subcutaneous of nude mouse microspheres under a500kHz alternating field.3Co42A microspheres in vitro of biocompatibility evaluation:Microspheres extracts were prepared according to national standards GB/T16886.521997(in vitro cytotoxicity test method). Mouse fibroblasts L929were incubated with the resulting extracts for72h. The shapes of cells were observed by microscope and the cell relative growth rate were determined by CCK-8assay..4Magnetic induction hyperthermia for tumor cells by Co42A microspheres:tumor cells were cocultured with Co42A microspheres in an alternating magnetic field. The relative growth rates were determined by CCK-8assay; the cellular morphology was observed under optical microscope after Giemsa staining. The relative growth rates of cells in sodium hyaluronate gel exposed to magnetic field were analyzed.ResultsThe Co42A microsphere, with average particle size of66.421μm, could be used for tumor hyperthermia. Scanning electron microscopy results showed that the microsphere had smooth surface; vibrating sample magnetometer showed that Co42A microspheres had ferromagnetism. When exposed to the external alternating magnetic field, the microspheres at different concentrations showed good heating performance.Sodium hyaluronate gel was chosen as the suspending agent to Co42A microspheres. There was no inhibiting effect on the temperature performance when the microsphere were in sodium hyaluronate gel, and this suspend series showed good temperature performances when they were injected in subcutaneous of nude mouse. Co42A has satisfied biocompatibility. No significant adverse effects on cell morphology and proliferation were observed.Tumor cells were effectively killed by co-culturing with Co42A microsphere exposed to the alternating magnetic field. Sodium hyaluronate gel promoted the hyperthermia effects of Co42A microspheres.ConclusionCo42A microspheres, having consistent form and size and good heating performance in an alternating magnetic field, can be injected into tumor when being suspended in sodium hyaluronate gel. Theses microspheres have good biocompatibility, can be used as magnetic induction hyperthermia media.