Surface modification of bioactive glass nanoparticles and the mechanical and biological properties of poly(L-lactide) composites

State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China.
Acta Biomaterialia (Impact Factor: 5.68). 08/2008; 4(4):1005-15. DOI: 10.1016/j.actbio.2008.02.013
Source: PubMed

ABSTRACT Novel bioactive glass (BG) nanoparticles/poly(L-lactide) (PLLA) composites were prepared as promising bone-repairing materials. The BG nanoparticles (Si:P:Ca=29:13:58 weight ratio) of about 40nm diameter were prepared via the sol-gel method. In order to improve the phase compatibility between the polymer and the inorganic phase, PLLA (M(n)=9700Da) was linked to the surface of the BG particles by diisocyanate. The grafting ratio of PLLA was in the vicinity of 20 wt.%. The grafting modification could improve the tensile strength, tensile modulus and impact energy of the composites by increasing the phase compatibility. When the filler loading reached around 4 wt.%, the tensile strength of the composite increased from 56.7 to 69.2MPa for the pure PLLA, and the impact strength energy increased from 15.8 to 18.0 kJ m(-2). The morphology of the tensile fracture surface of the composite showed surface-grafted bioactive glass particles (g-BG) to be dispersed homogeneously in the PLLA matrix. An in vitro bioactivity test showed that, compared to pure PLLA scaffold, the BG/PLLA nanocomposite demonstrated a greater capability to induce the formation of an apatite layer on the scaffold surface. The results of marrow stromal cell culture revealed that the composites containing either BG or g-BG particles have much better biocompatibility compared to pure PLLA material.

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    • "This may result in an ultimate depreciation of the mechanical properties [115] [128]. To avoid this and also a possible phase segregation [129], polymer/inorganic nanofiller compatibility is often improved by modifying the surface with organic molecules or surfactants [130] [131]. Despite this, the synergy between the two phases is still often inappropriate for the targeted application because of the heterogeneous degradation of the phases, the rapid loss of the composite mechanical properties, or the inappropriate release rate of ions/monomers from the material [93] [132]. "
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    Current Organic Chemistry 10/2014; 18(18):2299-2314. DOI:10.2174/1385272819666140806200355 · 2.54 Impact Factor
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    • "The attachment of organic molecules to the surface of bioglass particles has been previously proposed to improve the interphase adhesion between inorganic particles and polymer matrix [13] but has never been applied to avoid the degradation reaction between the SieO À groups present in the surface of bioglass particles and the C]O groups present in the polymer's backbone. Several methods have been reported in the current literature for the surface modification of inorganic bioactive particles [6] [13] [14]. However, all these surface modification methods require multiple steps of long duration and high quantities of organic solvents that can be harmful for health, limiting the application of these products in the biomedical field. "
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    Polymer Degradation and Stability 06/2013; 98(9):1717-1723. DOI:10.1016/j.polymdegradstab.2013.06.003 · 2.63 Impact Factor
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    • "Hexamethylene diisocyanate (HDI) has been reported as being acutely cytotoxic and an irritant to the skin and eyes. However, despite these reported toxicology issues there is also evidence for the effective use of HDI as a cross-linker in artificial extracellular matrix protein production genetically engineered from elastin and fibronectin derived repeat units [29], a modifier in drug delivery systems a surface-modifier/coupler in biocomposites [30] and as a surface modifier of calcium phosphate ceramics [30,31,32,33] investigated for use as medical implants. "
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