Study On Preparation, Osteoinduction Of Strontium-doped Mesoprous Hydroxyapatite And Properties Application In Drug Delivery

With the speeding tendency of aging society, bone fracture becomes the serious disease to threaten the human life and the need for bone regeneration is increasing dramatically. Tissue engineering is promising to address this challenge. Recently, many efforts have been directed towards developing nanostructured calcium phosphate(Ca P) biomaterials/scaffolds, which have the checmical/crystallographic similarities to inorganic components of bone. In our research, we designed and prepared four kinds of hydroxyapatites nanoparticles with different proportion strontium incorporation. The morphology, size distribution and composition of nanoparticles were measured using scanning electron microscope(SEM), X-ray diffractometer(XRD), dynamic light scattering(DLS) and specific surface area tester(BET). The biocompatibility, osteoconduction of the nanoparticles were evaluated by MTT, hemolytic and mineralization experiment. The behavior of drug absorbsion and releasing of alendronate(AL) were evaluated by UV-spectroscopy(UV), spectrofluorimetry(PL), fourier transform infrared spectrometry(FIR), thermogravimetric analysis(TGA) with HAP as drug delivery. The results indicated that morphology of the prepared nanoparticles could form nanorods with the lengths of 80~100 nm, diameters of around 20 nm and the mesopore size of 2–3 nm. The biocompatibility and osteoconduction were improved by incorporation of strontium, the alendronate(AL) was absorbed to the nanoparticle by electrostatic interaction, a relatively continuous release from the nanoparticles by diffusion. The capability to drug loading and releasing of CS3(20% Sr@HAP) is the best, the amount of AL adsorbed at 48 h is up to 0.85 mg(AL) / mg(carriers), the accumulated release amount of AL is about 76% at 15 d in vitro. Therefore, It is an ideal drug carrier delivery bisphosphate. Given the ability of HAP nano-carrier itself with promoting osteoblast differentiation and mineralization, the capacity of AL to inhibit osteoclast resorption. we hypothesized that the carrier and the drugs may play a synergistic therapeutic effect in the process to treatment of osteoporosis, it has potential applications in the treatment of osteoporosis.