Implantation of a biomaterial is one of the important trends in solving the problem of bone tissue loss. Calcium hydroxiapatite (HAp), as the most representative bone component is a serious candidate for such implantations. The synthetic polymer poly-L-lactide (PLLA) in HAp/PLLA is often used as a polymeric material, with a role in the substitution of bone tissue collagen fibers. Fibers of PLLA may strengthen HAp and its good bioresorption provides space for tissue remodeling. Differences in porosity, microstructure, compressive consistency as well as bioresorbility of HAp/ PLLA may be achieved by using PLLA with different molecular weights. In this study HAp/PLLA composites with PLLA of different molecular weights (50,000; 160,000 and 430,000) were implanted in mouse peritoneum in order to examine the influence of the molecular weight of PLLA on morphology changes. Microstructural changes of biomaterial (HAp/PLLA) surface were analyzed one week, three weeks and four months after their implantation using Scanning Electron Microscopy. The results showed a significant difference in tissue reactions on the applied biocomposites, depending on their molecular weight. The most intense proliferation of cells was induced by HAp/PLLA 50,000 compared to HAp/PLLA 430,000 and HAp/PLLA 160,000. In the vicinity of HAp/PLLA 430,000 abundant erythrocytes were observed. The differences in biological reactions on the examined biocomposites are significant for their practical applications. HAp/PLLA composite biomaterials of different types and resorption rates require specific designing and programming to become suitable for particular purposes in an organism.
If the inline PDF is not rendering correctly, you can download the PDF file here.
1. Keating FJ, McQueen MM. Substitutes for autologous bone graft in orthopaedic trauma. J Bone Joint Surg 2001; 83(1): 3-8.
2. Lazić Z, Bubalo M, Milović R, Matijević S, Magić M, Đorđević I. Comparison of resorbable membranes for guided bone regeneration of human and bovine origin. Acta Veterinaria- Beograd 2014; 64(4): 477-492.
3. Gao C, Deng Y, Feng P, Mao Z, Li P, Yang B, Deng J, Cao Y, Shuai C, Peng S. Current progress in bioactive ceramic scaffolds for bone repair and regeneration. Int J Mol Sci 2014; 15: 4714-4732.
4. Kurashina K, Kurita H, Takeuchi H, Hirano M, Klein C, de-Groot K. Osteogenesis in muscle with composite graft of hydroxyapatite and autogenous calvarial periosteum: A preliminary report. Biomaterials 1995; 16(2): 119-123.
5. Ripamonti U, Duneas N. Tissue engineering of bone by osteoinductive biomaterials. MRS Bulletin 1996; 21(11): 36-42.
6. Angelova N, Hunkeler D. Rationalizing the design of polymeric biomaterials. Trends in Biotechnology 1999; 17(10): 409-421.
7. Wang Z, Wang Y, Ito Y, Zhang P, Chen X. A comparative study on the in vivo degradation of poly(L-lactide) based composite implants for bone fracture fixation, Scientific Reports 2016; 9;6:20770
8. Yanagida H, Okada M,Masuda M, Narama I, Nakano S, Kitao S, Takakuda K, Furuzono T. Preparation and in vitro/in vivo evaluations of dimpled poly(l-lactic acid) fi bers mixed/ coated with hydroxyapatite nanocrystals. Journal of Artificial Organs 2011; 14, 331-341.
9. Freed L E, Vunjak-Novakovic G, Biron R J, Eagles D, Lesnoy D, Barlow S K, Langer R. Biodegradable polymer scaffolds for tissue engineering. Nature Biotechnology 1994; 12: 689-693.
10. Ignjatović N, Tomić S, Dakić M, Miljković M, Plavšić M, Uskoković D. Synthesis and properties of hydroxyapatite/poly-L-lactide composite biomaterials. Biomaterials 1999; 20(9): 809-816.
11. Nejati E, Firouzdor V, Eslaminejad M B, Bagheri F. Needle-like nano hydroxyapatite/ poly(L-lactide acid) composite scaffold for bone tissue engineering application. Materials Science and Engineering C 2009; 29: 942-949.
12. Ignjatović N, Savić V, Najman S, Plavšić M, Uskoković D. A study of HAp/PLLA composite as a substitute for bone powder, using FT-IR spectroscopy. Biomaterials 2001; 22(6): 571-575.
13. Najman S, Đorđević Lj, Savić V, Ignjatović N, Plavšić M, Uskoković D. Changes of HAp/PLLA biocomposites and tissue reaction after subcutaneous implantation. Facta Universitatis Series: Medicine and Biology 2003; 10(3): 131-134.
14. Najman S, Savic V, Djordjevic Lj. Ignjatovic N, Uskokovic D. Biological evaluation of hydroxyapatite/poly-L-lactide (HAp/PLLA) composite biomaterials with poly-L-lactide of different molecular weights intraperitoneally implanted into mice. Biomed Mater Eng 2004; 14(1): 61-70.
15. Persson M, Lorite SG, Kokkonen EH, Cho SW, Lehenkari PP, Skrifvars M, Tuukkanen J. Effect of bioactive extruded PLA/HA composite films on focal adhesion formation of preosteoblastic cells. Colloids and Surfaces B: Biointerfaces 2014; 121: 409-416.
16. Mansourizadeh F, Asadi A, Oryan S, Nematollahzadeh A, Dodel M, Asghari-Vostakolaei M. PLLA/HA Nano composite scaffolds for stem cell proliferation and differentiation in tissue engineering. Molecular Biology Research Communications 2013; 2(1-2): 1-10.
17. Mainil-Varlet P, Curtis R, Gogolewski S. Effect of in vivo and in vitro degradation on molecular and mechanical properties of various low-molecular-weight polylactides. J Biomed Mater Res 1997; 36(3): 360-80.
18. Podlaha J, Schwanhaeuser K. Experimental assessment of a new type of vascular prostheses with adiponectin (adipograft Ra 1vk 7/350) on sheep. Acta Veterinaria-Beograd 2014; 64(4): 426-437.