title: Fabrication and characterization of nano-composite scaffold of PLLA/silane modified hydroxyapatite.
abstract: In order to improve the interfacial connection of hydroxyapatite (HAP) to poly-l-lactic acid (PLLA), gamma-methacryloxypropyl-trimethoxysilane (gamma-MPS) was used as a coupling agent to modify the surface of nano-HAP (NHAP) particles. The FTIR and XPS results showed gamma-MPS was successfully bonded on the surface of NHAP. Silane modified nano-HAP (MNHAP) and PLLA were fabricated to nano-composite scaffold by a thermally induced phase separation method. The characterization of the composite scaffold showed that the scaffold had a nano-fibrous PLLA network (fiber size 100-800 nm), an interconnective microporous structure (1-8 microm) and high porosity (>90%). MNHAP was homogeneously distributed in the scaffold, also partly set in the nano-PLLA fibers. As a result, the compressive modulus and the protein adsorption of PLLA/MNHAP (80:20, w/w) composite scaffold increased to 4.2-fold and 2.8-fold compared with those of a pure PLLA scaffold. Incorporating MNHAP into PLLA network also buffered the pH reduction and reduced the weight loss in vitro degradation significantly.
authors.affiliation: Institute of Polymer Materials, Qingdao University, Qingdao, Shandong 266071, People's Republic of China. wangxjlt@yahoo.com.cn
authors.forename: Xuejun
authors.initials: X
authors.lastname: Wang
authors.forename: Guojun
authors.initials: G
authors.lastname: Song
authors.forename: Tao
authors.initials: T
authors.lastname: Lou
mesh_terms: D000327:Adsorption; D019245:Compressive Strength; D017886:Durapatite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000737:chemistry*; D008689:Methacrylates / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D011091:Polyesters; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D011506:Proteins / Q000737:chemistry; D012821:Silanes / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*; D056928:X-Ray Absorption Spectroscopy
chemical_list: D008689:Methacrylates; D011091:Polyesters; D011108:Polymers; D011506:Proteins; D012821:Silanes; C017492:methacryloxypropyltrimethoxysilane; D019344:Lactic Acid; C033616:poly(lactide); D017886:Durapatite