Functional Coating And Drug Loading Of Apatite Biomaterials

As a bioactive material,hydroxyapatite(HA,Ca10(PO4)6(OH)2)has been widely used in biomedical industry such as orthopedic and dental applications.It also has been reported that fluoride-substituted hydroxyapatites support cellular proliferation and colonization and promote bone growth.Polylactic acid blending hydroxyapatite 3D printing material with orthopedic drugs,can improve the biocompatibility of orthopedic biomaterials,and reduce the rejection of body.Based on the above considerations,the main contents of the paper are as follows:1.The stable aqueous dispersion of FHA nanoparticles was prepared by a wet chemical synthesis method.After purification,the dispersion of FHA nanoparticles was directly used as the liquid feedstock in SPS process to prepare nanostructured FHA coating.The morphology,element composition,and phase of the synthesized powders and coating were systematically characterized by the transmission electron microscope(TEM),field-emission scanning electron microscopy(FE-SEM),X-ray diffraction(XRD)analysis,Fourier-transform infrared spectroscopy(FTIR),X-ray photoelectronic spectroscopy(XPS),and Raman spectroscopy.The anticorrosion performance of the nanostructured FHA coating on stainless steel in phosphate-buffered saline(PBS)solution was studied by potentiodynamic polarization and electrochemical impedance spectroscopy(EIS).2.We prepared highly transparent ultra-thin and pure nano-HA coatings onto glass substrates by a convenient hydrothermal process,offering a stage for directly imaging real-time interactions between hydroxyapatite and bone cells under microscope.This transparent nanostructured coating simulates the native bone environment and reflects the state of the bone cells accurately.The ease of fabrication and the repeatability of this platform approach could open a host of biomedical imaging applications in bone biology research as well as bone drug development.3.Nanostructured dibasic calcium phosphate(DCP)coating was prepared on the surface of magnesium alloy via hydrothermal method.The nanomorphology of coating was characterized by scanning electron microscopy.Raman spectroscopy and X-ray diffraction confirmed the DCP phase of coating.The potentiodynamic polarization and electrochemical impedance spectroscopy(EIS)results prove that the nanostructured DCP coating can greatly enhance the anticorrosion performance of AZ31B Mg alloy in PBS solution.4.Bovine serum albumin(BSA)and alendronate sodium(ALN)were used as the model drug to study the encapsulation of BSA and ALN by polylactic acid blended hydroxyapatite prepared by ion gel method,in order to provide a sustained release effect reference for the application of 3D print orthopedic materials in protein drug delivery.