This study was a preliminary observation for a potential use of the bovine bone-based hydroxyapatite (b-HA)/poly(lactic acid) (PLA) composite as a biomaterial. SEM micrographs, XRD pattern, and FTIR spectrum of calcined bovine bone revealed that the obtained powder was in a form of crystalline carbonated HA, and highly agglomerated. The surface of HA powder was modified with either 3-aminopropyltriethoxysilane (APES) or 3-methacryloxypropyltrimethoxysilane (MPTS) in order to enhance the compatibility between b-HA and PLA matrix. TGA and GPC results revealed that the incorporation of silane-treated HA into the PLA matrix significantly increased thermal stability of the composites and decreased the thermal degradation of PLA chains. SEM micrographs revealed that modification of HA with APES or MPTS eased dispersion of HA in PLA matrix and enhanced interfacial adhesion between both phases. Therefore, the mechanical properties of silane treated HA/PLA composites were improved as compared with those of b-HA/PLA composites. In addition, in vitro cytotoxicity tests indicated that the extracts from all HA/PLA composites had no toxicity to human osteoblast cell.
Xu JL, Khor KA, Sui JJ, Zhang JH and Chen WNProtein expression profiles in osteoblasts in response to differentially shaped hydroxyapatite nanoparticles. Biomaterials2009; 30(29): 5385-5391.
2.
Shi Z., Huang X., Cai Y., Tang R. and Yang D.Size effect of hydroxyapatite nanoparticles on proliferation and apoptosis of osteoblast-like cells. Acta Biomater2009 ; 5(1): 338-345.
3.
Fathi MH, Hanifi A. and Mortazavi V.Preparation and bioactivity evaluation of bone-like hydroxyapatite nanopowder . J Mater Process Tech2008; 202(1-3): 536-542.
4.
Tadic D., Peters F. and Epple M.Continuous synthesis of amorphous carbonated apatites. Biomaterials2002; 23(12): 2553-2559.
5.
Pecheva EV, Pramatarova LD, Maitz MF, Pham MT and Kondyuirin AVKinetics of hydroxyapatite deposition on solid substrates modified by sequential implantation of Ca and P ions part II: morphological, composition and structure study. Appl Surf Sci2004; 235(1-2): 170-175.
6.
Shikinami Y. and Okuno M.Bioresorbable devices made of forged composites of hydroxyapatite (HA) particles and poly l-lactide (PLLA). Part II: practical properties of miniscrews and miniplates. Biomaterials2001; 22(23): 3197-3211.
7.
Deng X., Hao J and Wang C. Preparation and mechanical properties of nanocomposites of poly(D,L-lactide) with Ca-deficient hydroxyapatite nanocrystals. Biomaterials2001; 22(21): 2867-2873.
8.
Tsuji H. and Ikarashi K. In vitro hydrolysis of poly(L-lactide) crystalline residues as extended-chain crystallites III. Effects of pH and enzyme. Polym Degrad Stabil2004; 85(1): 647-656.
9.
Hofinann GO, Kluger P. and Fischer R.Biomechanical evaluation of a bioresorbable PLA dowel for arthroscopic surgery of the shoulder. Biomaterials1997 ; 18(21): 1441- 1445.
10.
Russias J., Saiz E., Nalla RK, Gryn K., Ritchie RO and Tomsia APFabrication and mechanical properties of PLA/HA composites: a study of in vitro degradation. Mater Sci Eng C2006 ; 26(8): 1289-1295.
11.
Zhang SM, Liu J., Zhou W., Cheng L. and Guo XDInterfacial fabrication and property of hydroxyapatite/ polylactide resorbable bone fixation composites. Curr Appl Phys2005 ; 5(5): 516-518.
12.
Dupraz AMP , Wijn, JR, Meer SAT and Groot K.Characterization of silane-treated hydroxyapatite powders for use as filler in biodegradable composites. J Biomed Mater Res1996; 30: 231-238.
13.
Liu Q., Wijn JR, Groot K. and Blitterswijk CASurface modification of nano-apatite by grafting organic polymer. Biomaterials1998; 19(11-12): 1067-1072.
14.
Suppakarn N., Sanmaung S., Ruksakulpiwat Y., Sutapun W., Lorprayoon C. and Ekgasit S. ( 2006). Mechanical properties of natural hydroxyapatite/PP composites . In: Annual Technical Conference 2006, The Society of Plastics Engineers, 2006, Charlotte, North Carolina, USA, pp.325-329.
15.
Landi E., Celotti G., Logroscino G. and Tampieri A.Carbonated hydroxyapatite as bone substitute. J Eur Ceram Soc2003; 23(15): 2931-2937.
16.
Murugan R. and Ramakrishna S.Effect of zirconia on the formation of calcium phosphate bioceramics under microwave irradiation. Mater Lett2003 ; 58(1-2): 230-234.
17.
Landi E., Tampieri A., Celotti G., Vichi L. and Sandri M.Influence of synthesis and sintering parameters on the characteristics of carbonate apatite. Biomaterials2004; 25(10): 1763-1770.
18.
Wen J., Li Y., Zuo Y., et al. Preparation and characterization of nano-hydroxyapatite/silicone rubber composite. Mater Lett2008; 62(19): 3307-3309.
19.
Mansur AAP , Nascimento OL, Vasconcelos WL and Mansur HSChemical functionalization of ceramic tile surfaces by silane coupling agents: polymer modified mortar adhesion mechanism implications. Mater Res2008; 11(3): 293-302.
20.
Ignjatovic N., Suljovrujic E., Simendic JB, Krakovsky I. and Uskokovic D.Evaluation of hot-pressed hydroxyapatite/poly-L-lactide composite biomaterial characteristics . J Biomed Mater Res B2004; 71(2): 284-294.
21.
Chen X., Guo C. and Zhao N.Preparation and characterization of the sol-gel nano-bioactive glasses modified by the coupling agent gamma-aminopropyltriethoxysilane. Appl Surf Sci2008; 255(2): 466-468.
22.
Fukushima K. , Tabuani D. and Camino G.Nanocomposites of PLA and PCL based on montmorillonite and sepiolite. Mat Sci Eng C 2009; 29(4): 1433- 1441.
23.
Zhu A., Cai A., Zhou W. and Shi Z.Effect of flexibility of grafted polymer on the morphology and property of nanosilica/PVC composites. Appl Surf Sci2008 ; 254(13): 3745-3752.
24.
Zuiderduin WCJ , Westzaan C., Huetink J. and Gaymans RJToughening of polypropylene with calcium carbonate particles. Polymer2003; 44(1): 261-275.
25.
Todo M., Park SD, Arakawa K. and Takenoshita Y.Relationship between microstructure and fracture behavior of bioabsorbable HA/PLLA composites. Compos: Part A, 2006; 37(12): 2221-2225.
26.
Takayama T. , Todo M. and Takano A.The effect of bimodal distribution on the mechanical properties of hydroxyapatite particle filled poly(L-lactide) composites . J Mech Behav Biomed2009; 2(1): 105-112.
27.
Vainio MH, Heino M. and Seppala JVReinforcement of biodegradable poly(ester-urethane) with fillers. Polymer1998; 39(4): 865-872.
28.
Hong Z., Zhang P., He C., et al. Nano-composite of poly(L-lactide) and surface grafted hydroxyapatite: mechanical properties and biocompatibility. Biomaterials2005; 26(32): 6296-6304.
