title: Preparation of chitosan/nano hydroxyapatite organic-inorganic hybrid microspheres for bone repair.
abstract: In this work, we encapsulated icariin (ICA) into chitosan (CS)/nano hydroxyapatite (nHAP) composite microspheres to form organic-inorganic hybrid microspheres for drug delivery carrier. The composition and morphology of composite microspheres were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and differential scanning calorimetry- thermogravimetric analysis (DSC-TGA). Moreover, we further studied the performance of swelling properties, degradation properties and drug release behavior of the microspheres. ICA, the extract of traditional Chinese medicine-epimedium, was combined to study drug release properties of the microspheres. ICA loaded microspheres take on a sustained release behavior, which can be not only ascribed to electrostatic interaction between reactive negative hydroxyl (OH) of ICA and positive amine groups (NH₂) of CS, but also depended on the homogeneous dispersion of HAP nanoparticles inside CS organic matrix. In addition, the adhesion and morphology of osteoblasts were detected by inverted fluorescence microscopy. The biocompatibility of CS/nHAP/ICA microspheres was evaluated by the MTT cytotoxicity assay, Hoechst 33258 and PI fluorescence staining. These studies demonstrate that composite microspheres provide a suitable microenvironment for osteoblast attachment and proliferation. It can be speculated that the ICA loaded CS-based organic-inorganic hybrid microspheres might have potential applications in drug delivery systems.
authors.affiliation: Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002, China. Electronic address: ibptcjd@fzu.edu.cn.
authors.forename: Jingdi
authors.initials: J
authors.lastname: Chen
authors.affiliation: Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002, China.
authors.forename: Panpan
authors.initials: P
authors.lastname: Pan
authors.affiliation: Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002, China.
authors.forename: Yujue
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002, China.
authors.forename: Shengnan
authors.initials: S
authors.lastname: Zhong
authors.affiliation: Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002, China; Institute of Biomedical Engineering, Chinese Academy of Medical Science & Peking Union Medical College, Tianjin 300192, China. Electronic address: zhangqiq@126.com.
authors.forename: Qiqing
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D001846:Bone Development; D002152:Calorimetry, Differential Scanning; D048271:Chitosan / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D053758:Nanoparticles; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D048271:Chitosan; D017886:Durapatite
keywords: Composite microspheres; Controlled release; In situ; Nano hydroxyapatite; Organic–inorganic hybrid