RESUMO
In the present study, magnetic glass ceramics in the system Fe2O3 â TiO2 â P2O5 â SiO2 â MO (M=Mg, Ca, Mn, Cu, Zn or Ce) are prepared. The effect of adding different cations on the thermal behavior, developed phases, microstructure and magnetic properties is studied using differental thermal analysis (DTA), X-ray diffraction analysis (XRD), transmission electron microscope (TEM), FT-infrared transmission (FT-IR) and vibrating sample magnetometer (VSM) respectively. The magnetic glass ceramics are tested as delivery systems for 5-fluorouracil. Modeling and analysis of release kinetics are addressed. The application of Higuchi square root of time model and the first order release model indicated that, 5-FU is released by diffusion controlled mechanisms, and that its released rate depends greatly on the concentration of loaded drug during the loading stage. The obtained results suggested that, the prepared magnetic glass ceramics can be used for cancer treatment by hyperthermia and/or by localized delivery of therapeutic doses of 5-fluorouracil.
Assuntos
Cerâmica/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Fluoruracila/química , Magnetismo , Materiais Biocompatíveis , Cristalização , Compostos Férricos/química , Fluoruracila/farmacologia , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Compostos de Fósforo/química , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio/química , Difração de Raios XRESUMO
The present study aimed at studying the acceleration of the bioactive layer on the surface of ferrimagnetic glass ceramic with a basic composition 40Fe2O3-15P2O5-20SiO2-5TiO2 through the addition of 20% of different types of metal oxides like MgO or CaO or MnO or CuO or ZnO or CeO2. SEM, EDAX, and ICP were applied to present the results of the study. SEM and EDAX measurements indicated the presence of apatite layer formed on the surface of the prepared glass ceramics after immersion in SBF within 7 to 30 days. The investigation of the results clarified that the addition of CaO or ZnO accelerated the formation of apatite on the surfaces of the samples in the simulated body fluid faster than other metal oxides. Inductive coupled plasma (ICP) analysis shows the evolution of ion extraction by the simulated body fluid solution (SBF) with time in relation to the elemental composition.