Abstract: Objective:To prepare resveratrol（Res）/mesoporous silica nanoparticles（MSNs）/bipolar calcium phosphate (BCP) composite microspheres and to test their physicochemical properties and biocompatibility. Methods： MSNs hollow microspheres were prepared by emulsion polymerization and hard template method and loaded with Res and BCP, the microstructure of the composite microsphere scaffold was observed by transmission electron microscope (TEM) and scanning electron microscope (SEM), the specific surface area and pore size distribution of the microsphere were analyzed by specific surface area and porosity test, the internal chemical structure of the scaffold was analyzed by fourier transform infrared spectroscopy (FTIR), the material composition of the scaffold was analyzed by Xray diffraction (XRD), the drug release amount of Res was tested by drug release performance test, and the degradation performance of the composite microsphere scaffold was analyzed by degradation performance test. Human dental pulp stem cells (hDPSCs) were co-cultured with the composite microsphere scaffold extract, the cell viability was detected by CCK-8, and the cell adhesion was observed by SEM to evaluate the biocompatibility of composite microspheres scaffolds for hDPSCs. Results： The dispersion of MSNs was good under TEM, and the combination of MSNs and BCP was good under SEM. The test results of specific surface area and porosity showed that the composite microspheres had ultrasmall mesoporous pore size and large specific surface area. The results of FTIR analysis showed the presence of hydroxyapatite (HAp), β-tricalcium phosphate (β-TCP), Res and silica (SiO2) in the composite microsphere scaffold. XRD patterns showed that the characteristic peaks of HAp, β-TCP and SiO2 in Res/MSNs/BCP scaffold materials. The results of drug release test of different quantities of Res showed that the release concentration gradually stabilized with the extension of time, and the release amount increased with the increase of Res weight (P＜0.05). The degradation experiment results showed that the degradation rate of MSNs was the slowest, while the degradation rate of BCP was faster, the degradation rate of MSNs/BCP was between that of MSNs and BCP, and the degradation rate was faster at the initial stage, and gradually stabilized after 21 days (P＜0.05). The results of CCK-8 showed that 1.0% extract of composite scaffold loaded with different Res had no cytotoxicity, and the viability of hDPSCs cells decreased with the increase of extract concentration (P＜0.05). The results of cell adhesion showed that the surface structure of composite scaffold material was suitable for the adhesion and growth of hDPSCs. Conclusions： Res/MSNs/BCP composite microspheres scaffolds have good characterization, physicochemical properties, no cytotoxicity and good biocompatibility. 

Key words: Periodontitis, Resveratrol, Mesoporous silica, Biphasic calcium phosphate, Composite microspheres