title: Bio-templated bioactive glass particles with hierarchical macro-nano porous structure and drug delivery capability.
abstract: Hierarchically porous bioactive glass particles (BGPs) were synthesized by a facile sol-gel process using pollen grains as the templates. The synthesized pollen-templated bioactive glass particles (PBGPs) exhibited dual macro-nano porous structure. The macro pores (∼ 1 μm) were inherited from the template of pollen grains while the nano pores (∼ 9.5 nm) were induced by the intrinsic mechanism of the sol-gel process. PBGPs possessed a high specific surface area (111.4m(2)/g) and pore volume (0.35 cm(3)/g). Hydroxyapatite (HA) formation on PBGPs was detected within 3 days after immersion in simulated body fluid (SBF). Due to their larger specific surface area and pore volume, PBGPs could be loaded with more tetracycline hydrochloride (TCH) than non-templated BGPs and conventional melt-derived 45S5 BGPs. In addition, PBGPs exhibited a low initial burst release (within 10% of the loaded amount) within 18 h and a sustained release with a two-stage release pattern for up to 6 days in phosphate buffered saline (PBS). The antibacterial assay confirmed that the TCH-loaded PBGPs could release TCH within 5 days, and the released TCH could reach the minimum inhibitory concentration (MIC) against Escherichia coli. MTT assay indicated that PBGPs showed non-cytotoxic effects toward human hepatocellular carcinoma (Hep G2) cells after co-culture for up to 72 h in vitro. These results showed that the biocompatible hierarchically macro-nano porous PBGPs are potential for bone regeneration and local drug delivery applications.
authors: Institute of Biomaterials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Cauerstrasse 6, 91058 Erlangen, Germany.
authors: Kai
authors: K
authors: Zheng
authors: Institute of Biomaterials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Cauerstrasse 6, 91058 Erlangen, Germany.
authors: Judith A
authors: JA
authors: Bortuzzo
authors: Food Chemistry Unit, Department of Chemistry and Pharmacy, Emil Fischer Center, University of Erlangen-Nuremberg, Schuhstr. 19, 91052 Erlangen, Germany.
authors: Yufang
authors: Y
authors: Liu
authors: Institute of Biomaterials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Cauerstrasse 6, 91058 Erlangen, Germany.
authors: Wei
authors: W
authors: Li
authors: Food Chemistry Unit, Department of Chemistry and Pharmacy, Emil Fischer Center, University of Erlangen-Nuremberg, Schuhstr. 19, 91052 Erlangen, Germany.
authors: Monika
authors: M
authors: Pischetsrieder
authors: Institute of Polymer Materials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Martensstrasse 7, 91058 Erlangen, Germany.
authors: Judith
authors: J
authors: Roether
authors: Department of Surgery, Klinikum rechts der Isar, Techenische Universitaet München, Ismaninger Str. 22, 81675 München, Germany.
authors: Miao
authors: M
authors: Lu
authors: Institute of Biomaterials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Cauerstrasse 6, 91058 Erlangen, Germany. Electronic address: aldo.boccaccini@ww.uni-erlangen.de.
authors: Aldo R
authors: AR
authors: Boccaccini
mesh_terms: D000900:Anti-Bacterial Agents; D002516:Ceramics; D004337:Drug Carriers; D056945:Hep G2 Cells; D006801:Humans; D049329:Nanostructures; D016062:Porosity; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; C022107:Bioglass; D004337:Drug Carriers
keywords: Bio-template; Bioactive glass; Drug delivery; Hierarchical pores