Hydroxyapatite and chitosan

Kim S-H, Lim B-K, Sun F (2009) Preparation of high flexible composite film of hydroxyapatite and chitosan. Polym Bull 62 111-118... 

Li QL, Wu MY, Tang LL et al (2008) Bioactivity of a novel nano-composite of hydroxyapatite and chitosan-phosphorylated chitosan polyelectrolyte complex. J Bioact Compat Polym... 

Teng SH, Lee EJ, Wang P et al (2008) Three-layered membranes of collagen/hydroxyapatite and chitosan for guided bone regeneration. J Biomed Mater Res Part B Appl Biomater 87B 132-138... 

Venkatesan, J., Pallela, R., Bhatnagar, I., Kim, S.-K., 2012a. Chitosan-amylopectin/ hydroxyapatite and chitosan-chondroitin sulphate/hydroxyapatite composite scaffolds for bone tissue engineering. International Journal of Biological Macromolecules 51 (5), 1033-1042. 

Similarly, a composite of hydroxyapatite and a network formed via cross-linking of chitosan and gelatin with glutaraldehyde was developed by Yin et al. [ 169]. A porous material, with similar organic-inorganic constituents to that of natural bone, was made by the sol-gel method. The presence of hydroxyapatite did not retard the formation of the chitosan-gelatin network. On the other hand, the polymer matrix had hardly any influence on the high crystallinity of hydroxyapatite. 

Muzzarelli et al. (2000) described a method for coating prosthetic articles with chitosan-oxychitin. Plates of titanium (Ti) and its alloys were plasma sprayed with hydroxyapatite and glass layers, and subsequently a chitosan coat was deposited on the plasma-sprayed layers using chitosan acetate. These layers were treated with 6-oxychitin to form a polyelectrolytic complex. This complex was optionally contacted with l-ethyl-3-(3-dimethylami-nopropyl) carbodiimide at 4°C for 2 hours to form amide links between the two polysaccharides, or acetylation with acetic anhydride in methanol to obtain a chitin film. In all cases, the modified coats were insoluble, uniformly flat, and smooth. Prosthetic materials coated with chitosan-oxychitin were capable of provoking colonization by cells, osteogenesis, and osteointegration. 

Verma, D., Katti, KS., Katti, DR., Mohanty, B. 2008. Mechanical response and multilevel structure of bio-mimetic hydroxyapatite/polygalacturonic/chitosan nanocomposites. Materials Science Engineering C-28 399-405. 

Correlo, V.M., et al., 2005. Hydroxyapatite reinforced chitosan and polyester blends for biomedical applications. Macromolecular Materials and Engineering 290 (12), 1157-1165. 

Li, M., Wang, Y, Lin, Q., et al., 2013. In situ synthesis and biocompatibility of nano hydroxyapatite on pristine and chitosan functionalized graphene oxide. Journal of Materials Chemistry B... 

Tavakol, S., Nikpour, M., Amani, A., et al., 2013. Bone regeneration based on nano-hydroxyapatite and hydroxyapatite/chitosan nanocomposites an in vitro and in vivo comparative study. Journal of Nanoparticle Research 15 (1), 1-16. 

The cell growth was much faster on the chitosan-hydroxyapatite scaffolds with the glass than on the chitosan-hydroxyapatite scaffold without the glass. The total protein content of cells increased over time on both composites. The cells on the chitosan-hydroxyapatite-glass also expressed significantly higher amount of alkaline phosphatase at days 7 and 11 and osteocalcin at day 7 than those on chitosan-hydroxyapatite [165]. 

Chitosan scaffolds were reinforced with beta-tricalciiun phosphate and calcium phosphate invert glass [177]. Along the same line, composites of Loligo beta-chitin with octacalcium phosphate or hydroxyapatite were prepared by precipitation of the mineral into a chitin scaffold by means of a double diffusion system. The octacalciiun phosphate crystals with the usual form of 001 blades grew inside chitin layers preferentially oriented with the 100 faces parallel to the surface of the squid pen and were more stable to hy-... 

The chitosan-bonded hydroxyapatite bone-filHng paste was made as follows. Chitosan (0.5 g) was dissolved in malic acid (0.5 g) solution made with saline, and a chitosan film was formed by mixing this solution with hydrox-... 

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