Skip to main content

Advertisement

Log in

Synthesis and Characterization of Natural Nano-hydroxyapatite Derived from Turkey Femur-Bone Waste

  • Published:
Applied Biochemistry and Biotechnology Aims and scope Submit manuscript

Abstract

Hydroxyapatite (HAp) is a bioactive and vital material which has found many applications in the biomedical and clinical fields. This bio-ceramic powder can be synthesized via different bio-waste materials. In this study, the production of natural nanohydroxyapatite was produced through calcination of untreated turkey femur-bone waste powder at 850 °C followed by ball milling the powder. The obtained powder was characterized using X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis. The morphology, size, and elemental composition of obtained turkey hydroxyapatite (THA) particles were investigated by scanning electron microcopy (SEM), transmission electron microcopy (TEM), and energy dispersive spectroscopy (EDS) analysis, in which the average particle size of ball milled THA was found to be about 85 nm with a Ca/P ratio of 1.63. The powder was then cold pressed and later sintered at 850, 950, 1050, and 1150 °C to evaluate its mechanical properties in terms of compressive strength and hardness. The results revealed that the strength and hardness of the samples increased by increasing the sintering temperature up to 1150 °C. Finally, the maximum values of hardness and compressive strength of the sintered THA were obtained at 1150 °C (37.44 MPa and 3.2 GPa, respectively).

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8

Similar content being viewed by others

References

  1. Shi, P., Liu, M., Fan, F., Yu, C., Lu, W., & Du, M. (2018). Characterization of natural hydroxyapatite originated from fish bone and its biocompatibility with osteoblasts. Materials Science and Engineering C, 90, 706–712.

    CAS  PubMed  Google Scholar 

  2. Chang, J. H., Liu, J. F., Sun, Y. S., Wu, C. P., Huang, H. H., & Han, Y. (2017). Mesoporous surface topography promotes bone cell differentiation on low elastic modulus Ti–25Nb–25Zr alloys for bone implant applications. Journal of Alloys and Compounds, 707, 220–226.

    CAS  Google Scholar 

  3. Feng, W., Feng, S., Tang, K., He, X., Jing, A., & Liang, G. (2017). A novel composite of collagen-hydroxyapatite/kappa-carrageenan. Journal of Alloys and Compounds, 693, 482–489.

    CAS  Google Scholar 

  4. Huang, Y., Xu, Z., Zhang, X., Chang, X., Zhang, X., Li, Y., Ye, T., Han, R., Han, S., Gao, Y., Du, X., & Yang, H. (2017). Nanotube-formed Ti substrates coated with silicate/silver co-doped hydroxyapatite as prospective materials for bone implants. Journal of Alloys and Compounds, 697, 182–199.

    CAS  Google Scholar 

  5. Lim, S.-R., Gooi, B.-H., Singh, M., & Gam, L.-H. (2011). Analysis of differentially expressed proteins in colorectal cancer using hydroxyapatite column and SDS-PAGE. Applied Biochemistry and Biotechnology, 165(5), 1211–1224.

    CAS  PubMed  Google Scholar 

  6. Sharifianjazi, F., Parvin, N., & Tahriri, M. (2017). Synthesis and characteristics of sol-gel bioactive SiO2-P2O5-CaO-Ag2O glasses. Journal of Non-Crystalline Solids, 476, 108–113.

    CAS  Google Scholar 

  7. Moghanian, A., Sedghi, A., Ghorbanoghli, A., & Salari, E. (2018). The effect of magnesium content on in vitro bioactivity, biological behavior and antibacterial activity of sol–gel derived 58S bioactive glass. Ceramics International, 44(8), 9422–9432.

    CAS  Google Scholar 

  8. Zilm, M. E., Yu, L., Hines, W. A., & Wei, M. (2018). Magnetic properties and cytocompatibility of transition-metal-incorporated hydroxyapatite. Materials Science and Engineering C, 87, 112–119.

    CAS  PubMed  Google Scholar 

  9. Pandey, A., Midha, S., Sharma, R. K., Maurya, R., Nigam, V. K., Ghosh, S., & Balani, K. (2018). Antioxidant and antibacterial hydroxyapatite-based biocomposite for orthopedic applications. Materials Science and Engineering C, 88, 13–24.

    CAS  PubMed  Google Scholar 

  10. Feng, S., He, F., & Ye, J. (2018). Hierarchically porous structure, mechanical strength and cell biological behaviors of calcium phosphate composite scaffolds prepared by combination of extrusion and porogen burnout technique and enhanced by gelatin. Materials Science and Engineering C, 82, 217–224.

    CAS  PubMed  Google Scholar 

  11. Sharifi Sedeh, E., Mirdamadi, S., Sharifianjazi, F., & Tahriri, M. (2015). Synthesis and evaluation of mechanical and biological properties of scaffold prepared from Ti and Mg with different volume percent. Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry, 45(7), 1087–1091.

    CAS  Google Scholar 

  12. Maji, K., Dasgupta, S., Pramanik, K., & Bissoyi, A. (2018). Preparation and characterization of gelatin-chitosan-nanoβ-TCP based scaffold for orthopaedic application. Materials Science and Engineering C, 86, 83–94.

    CAS  PubMed  Google Scholar 

  13. Yin, H., Yang, C., Gao, Y., Wang, C., Li, M., Guo, H., & Tong, Q. (2018). Fabrication and characterization of strontium-doped borate-based bioactive glass scaffolds for bone tissue engineering. Journal of Alloys and Compounds, 743, 564–569.

    CAS  Google Scholar 

  14. Maachou, H., Bal, K., Bal, Y., Chagnes, A., Cote, G., & Aliouche, D. (2012). In vitro biomineralization and bulk characterization of chitosan/hydroxyapatite composite microparticles prepared by emulsification cross-linking method: orthopedic use. Applied Biochemistry and Biotechnology, 168(6), 1459–1475.

    CAS  PubMed  Google Scholar 

  15. Tahriri, M., & Moztarzadeh, F. (2014). Preparation, characterization, and in vitro biological evaluation of PLGA/nano-fluorohydroxyapatite (FHA) microsphere-sintered scaffolds for biomedical applications. Applied Biochemistry and Biotechnology, 172(5), 2465–2479.

    CAS  PubMed  Google Scholar 

  16. Vallet-Regí, M., & González-Calbet, J. M. (2004). Calcium phosphates as substitution of bone tissues. Progress in Solid State Chemistry, 32(1–2), 1–31.

    Google Scholar 

  17. Bodhak, S., Bose, S., & Bandyopadhyay, A. (2009). Role of surface charge and wettability on early stage mineralization and bone cell–materials interactions of polarized hydroxyapatite. Acta Biomaterialia, 5(6), 2178–2188.

    CAS  PubMed  Google Scholar 

  18. Lawton, D., Lamaletie, M., & Gardner, D. (1989). Biocompatibility of hydroxyapatite ceramic: Response of chondrocytes in a test system using low temperature scanning electron microscopy. Journal of Dentistry, 17(1), 21–27.

    CAS  PubMed  Google Scholar 

  19. Aoki, H. (1994). Medical applications of hydroxyapatite, Ishiyaku euro America. Tokyo: Google Scholar.

    Google Scholar 

  20. Do Prado Ribeiro, D. C., de Abreu Figueira, L., Mardegan Issa, J. P., Dias Vecina, C. A., JosÉDias, F., & Da Cunha, M. R. (2012). Study of the osteoconductive capacity of hydroxyapatite implanted into the femur of ovariectomized rats. Microscopy Research and Technique, 75(2), 133–137.

    PubMed  Google Scholar 

  21. Hui, P., Meena, S., Singh, G., Agarawal, R., & Prakash, S. (2010). Synthesis of hydroxyapatite bio-ceramic powder by hydrothermal method. Journal of Minerals and Materials Characterization and Engineering, 9(08), 683–692.

    Google Scholar 

  22. Cozza, N., Monte, F., Bonani, W., Aswath, P., Motta, A., & Migliaresi, C. (2017). Bioactivity and mineralization of natural hydroxyapatite from cuttlefish bone and Bioglass® co-sintered bioceramics. Journal of Tissue Engineering and Regenerative Medicine.

  23. Fang, B., Wan, Y.-Z., Tang, T.-T., Gao, C., & Dai, K.-R. (2009). Proliferation and osteoblastic differentiation of human bone marrow stromal cells on hydroxyapatite/bacterial cellulose nanocomposite scaffolds. Tissue Engineering Part A, 15(5), 1091–1098.

    CAS  PubMed  Google Scholar 

  24. Wang, X., Qian, C., & Yu, X. (2014). Synthesis of nano-hydroxyapatite via microbial method and its characterization. Applied Biochemistry and Biotechnology, 173(4), 1003–1010.

    CAS  PubMed  Google Scholar 

  25. Pal, A., Maity, S., Chabri, S., Bera, S., Chowdhury, A. R., Das, M., & Sinha, A. (2017). Mechanochemical synthesis of nanocrystalline hydroxyapatite from Mercenaria clam shells and phosphoric acid. Biomedical Physics & Engineering Express, 3(1), 015010.

    Google Scholar 

  26. Youness, R. A., Taha, M. A., Elhaes, H., & Ibrahim, M. (2017). Molecular modeling, FTIR spectral characterization and mechanical properties of carbonated-hydroxyapatite prepared by mechanochemical synthesis. Materials Chemistry and Physics, 190, 209–218.

    CAS  Google Scholar 

  27. Fakharzadeh, A., Ebrahimi-Kahrizsangi, R., Nasiri-Tabrizi, B., & Basirun, W. J. (2017). Effect of dopant loading on the structural features of silver-doped hydroxyapatite obtained by mechanochemical method. Ceramics International, 43(15), 12588–12598.

    CAS  Google Scholar 

  28. Tekiyeh, R. M., Najafi, M., & Shahraki, S. Machinability of AA7075-T6/carbon nanotube surface composite fabricated by friction stir processing. Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering, 0(0), 0954408918809618.

  29. Faksawat, K., Sujinnapram, S., Limsuwan, P., Hoonnivathana, E., & Naemchanthara, K. (2015). Preparation and characteristic of hydroxyapatite synthesized from cuttlefish bone by precipitation method. Advanced Materials Research, Trans Tech Publ, 1125, 421–425.

    Google Scholar 

  30. Jazi, F. S., Parvin, N., Rabiei, M., Tahriri, M., Shabestari, Z. M., & Azadmehr, A. R. (2012). Effect of the synthesis route on the grain size and morphology of ZnO/Ag nanocomposite. Journal of Ceramic Processing Research, 13(5), 523–526.

    Google Scholar 

  31. Goto, T., & Sasaki, K. (2016). Synthesis of morphologically controlled hydroxyapatite from fish bone by urea-assisted hydrothermal treatment and its Sr2+ sorption capacity. Powder Technology, 292, 314–322.

    CAS  Google Scholar 

  32. Jazi, F. S., Parvin, N., Tahriri, M., Alizadeh, M., Abedini, S., & Alizadeh, M. (2014). The relationship between the synthesis and morphology of SnO2-Ag2O nanocomposite. Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry, 44(5), 759–764.

    CAS  Google Scholar 

  33. Anwar, A., & Akbar, S. (2018). Novel continuous microwave assisted flow synthesis of nanosized manganese substituted hydroxyapatite. Ceramics International, 44(9), 10878–10882.

    CAS  Google Scholar 

  34. Domínguez-Trujillo, C., Peón, E., Chicardi, E., Pérez, H., Rodríguez-Ortiz, J., Pavón, J., García-Couce, J., Galván, J., García-Moreno, F., & Torres, Y. (2018). Sol-gel deposition of hydroxyapatite coatings on porous titanium for biomedical applications. Surface and Coatings Technology, 333, 158–162.

    Google Scholar 

  35. Tseng, Y.-H., Kuo, C.-S., Li, Y.-Y., & Huang, C.-P. (2009). Polymer-assisted synthesis of hydroxyapatite nanoparticle. Materials Science and Engineering: C, 29(3), 819–822.

    CAS  Google Scholar 

  36. Apalangya, V., Rangari, V., Jeelani, S., Dankyi, E., Yaya, A., & Darko, S. (2018). Rapid microwave synthesis of needle-liked hydroxyapatite nanoparticles via template directing ball-milled spindle-shaped eggshell particles. Ceramics International, 44(6), 7165–7171.

    CAS  Google Scholar 

  37. Jahan, S. A., Mollah, M. Y. A., Ahmed, S., & Susan, M. A. B. H. (2017). Nano-hydroxyapatite prepared from eggshell-derived calcium-precursor using reverse microemulsions as nanoreactor. Materials Today: Proceedings, 4(4), 5497–5506.

    Google Scholar 

  38. Hammood, A. S., Hassan, S. S., & Alkhafagy, M. T. (2017). Access to optimal calcination temperature for nanoparticles synthesis from hydroxyapatite bovine femur bone waste. Nano Biomedicine Engineering, 3(9), 228–235.

    Google Scholar 

  39. Amna, T. (2018). Valorization of bone waste of Saudi Arabia by synthesizing hydroxyapatite. Applied Biochemistry and Biotechnology, 186(3), 779–788.

    CAS  PubMed  Google Scholar 

  40. Nandi, S. K., Kundu, B., Mukherjee, J., Mahato, A., Datta, S., & Balla, V. K. (2015). Converted marine coral hydroxyapatite implants with growth factors: In vivo bone regeneration. Materials Science and Engineering: C, 49, 816–823.

    CAS  Google Scholar 

  41. Green, D. W., Ben-Nissan, B., Yoon, K. S., Milthorpe, B., & Jung, H.-S. (2017). Natural and synthetic coral biomineralization for human bone revitalization. Trends in Biotechnology, 35(1), 43–54.

    CAS  PubMed  Google Scholar 

  42. Yamamura, H., da Silva, V. H. P., Ruiz, P. L. M., Ussui, V., Lazar, D. R. R., Renno, A. C. M., & Ribeiro, D. A. (2018). Physico-chemical characterization and biocompatibility of hydroxyapatite derived from fish waste. Journal of the Mechanical Behavior of Biomedical Materials, 80, 137–142.

    CAS  PubMed  Google Scholar 

  43. Jaber, H. L., Hammood, A. S., & Parvin, N. (2018). Synthesis and characterization of hydroxyapatite powder from natural Camelus bone. Journal of the Australian Ceramic Society, 54(1), 1–10.

    Google Scholar 

  44. Ripamonti, U., Crooks, J., Khoali, L., & Roden, L. (2009). The induction of bone formation by coral-derived calcium carbonate/hydroxyapatite constructs. Biomaterials, 30(7), 1428–1439.

    CAS  PubMed  Google Scholar 

  45. Akram, M., Ahmed, R., Shakir, I., Ibrahim, W. A. W., & Hussain, R. (2014). Extracting hydroxyapatite and its precursors from natural resources. Journal of Materials Science, 49(4), 1461–1475.

    CAS  Google Scholar 

  46. Gutowska, I., Machoy, Z., & Machaliński, B. (2005). The role of bivalent metals in hydroxyapatite structures as revealed by molecular modeling with the HyperChem software. Journal of Biomedical Materials Research Part A, 75(4), 788–793.

    PubMed  Google Scholar 

  47. Heidari, F., Razavi, M., Ghaedi, M., Forooghi, M., Tahriri, M., & Tayebi, L. (2017). Investigation of mechanical properties of natural hydroxyapatite samples prepared by cold isostatic pressing method. Journal of Alloys and Compounds, 693, 1150–1156.

    CAS  Google Scholar 

  48. Ayatollahi, M. R., Yahya, M. Y., Asgharzadeh Shirazi, H., & Hassan, S. A. (2015). Mechanical and tribological properties of hydroxyapatite nanoparticles extracted from natural bovine bone and the bone cement developed by nano-sized bovine hydroxyapatite filler. Ceramics International, 41(9, Part A), 10818–10827.

    CAS  Google Scholar 

  49. Coelho, T., Nogueira, E., Weinand, W., Lima, W., Steimacher, A., Medina, A., Baesso, M., & Bento, A. (2007). Thermal properties of natural nanostructured hydroxyapatite extracted from fish bone waste. Journal of Applied Physics, 101(8), 084701.

    Google Scholar 

  50. Masoudian, A., Karbasi, M., SharifianJazi, F., & Saidi, A. (2013). Developing Al2O3-TiC in-situ nanocomposite by SHS and analyzingtheeffects of Al content and mechanical activation on microstructure. Journal of Ceramic Processing Research, 14(4), 486–491.

    Google Scholar 

  51. Alizadeh, M., Sharifianjazi, F., Haghshenasjazi, E., Aghakhani, M., & Rajabi, L. (2015). Production of nanosized boron oxide powder by high-energy ball milling. Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry, 45(1), 11–14.

    CAS  Google Scholar 

  52. Javidi, M., Javadpour, S., Bahrololoom, M. E., & Ma, J. (2008). Electrophoretic deposition of natural hydroxyapatite on medical grade 316L stainless steel. Materials Science and Engineering: C, 28(8), 1509–1515.

    CAS  Google Scholar 

  53. Werner, J., Linner-Krčmar, B., Friess, W., & Greil, P. (2002). Mechanical properties and in vitro cell compatibility of hydroxyapatite ceramics with graded pore structure. Biomaterials, 23(21), 4285–4294.

    CAS  PubMed  Google Scholar 

  54. Heidari, F., Bahrololoom, M. E., Vashaee, D., & Tayebi, L. (2015). In situ preparation of iron oxide nanoparticles in natural hydroxyapatite/chitosan matrix for bone tissue engineering application. Ceramics International, 41(2, Part B), 3094–3100.

    CAS  Google Scholar 

  55. Shipman, P., Foster, G., & Schoeninger, M. (1984). Burnt bones and teeth: An experimental study of color, morphology, crystal structure and shrinkage. Journal of Archaeological Science, 11(4), 307–325.

    Google Scholar 

  56. Bahrololoom, M., Javidi, M., Javadpour, S., & Ma, J. (2009). Characterisation of natural hydroxyapatite extracted from bovine cortical bone ash. Journal of Ceramic Processing Research, 10(2), 129–138.

    Google Scholar 

  57. Herliansyah, M., Nasution, D., Shukor, B. A., Hamdi, M., Ide-Ektessabi, A., Wildan, M. W., & Tontowi, A. (2007). Preparation and characterization of natural hydroxyapatite: A comparative study of bovine bone hydroxyapatite and hydroxyapatite from calcite. Materials Science Forum, Trans Tech Publ, 1441–1444.

  58. Kim, Y. G., Seo, D. S., & Lee, J. K. (2008). Dissolution of synthetic and bovine bone-derived hydroxyapatites fabricated by hot-pressing. Applied Surface Science, 255(2), 589–592.

    CAS  Google Scholar 

  59. Mondal, S., Pal, U., & Dey, A. (2016). Natural origin hydroxyapatite scaffold as potential bone tissue engineering substitute. Ceramics International, 42(16), 18338–18346.

    CAS  Google Scholar 

  60. Boskey, A., & Camacho, N. P. (2007). FT-IR imaging of native and tissue-engineered bone and cartilage. Biomaterials, 28(15), 2465–2478.

    CAS  PubMed  Google Scholar 

  61. Gibson, I. R., & Bonfield, W. (2002). Novel synthesis and characterization of an AB-type carbonate-substituted hydroxyapatite. Journal of Biomedical Materials Research, 59(4), 697–708.

    CAS  PubMed  Google Scholar 

  62. Joschek, S., Nies, B., Krotz, R., & Göpferich, A. (2000). Chemical and physicochemical characterization of porous hydroxyapatite ceramics made of natural bone. Biomaterials, 21(16), 1645–1658.

    CAS  PubMed  Google Scholar 

  63. Ramesh, S., Natasha, A., Tan, C., Bang, L. T., Ching, C., & Chandran, H. (2016). Direct conversion of eggshell to hydroxyapatite ceramic by a sintering method. Ceramics International, 42(6), 7824–7829.

    CAS  Google Scholar 

  64. Ghomi, H., Fathi, M., & Edris, H. (2012). Effect of the composition of hydroxyapatite/bioactive glass nanocomposite foams on their bioactivity and mechanical properties. Materials Research Bulletin, 47(11), 3523–3532.

    CAS  Google Scholar 

  65. Lü, X. Y., Fan, Y. B., Gu, D., & Cui, W. (2007). Preparation and characterization of natural hydroxyapatite from animal hard tissues. Key Engineering Materials, Trans Tech Publ, 342-343, 213–216.

    Google Scholar 

  66. Ramesh, S., Loo, Z. Z., Tan, C. Y., Chew, W. J. K., Ching, Y. C., Tarlochan, F., Chandran, H., Krishnasamy, S., Bang, L. T., & Sarhan, A. A. D. (2018). Characterization of biogenic hydroxyapatite derived from animal bones for biomedical applications. Ceramics International, 44(9), 10525–10530.

    CAS  Google Scholar 

  67. Wang, J., & Shaw, L. L. (2009). Nanocrystalline hydroxyapatite with simultaneous enhancements in hardness and toughness. Biomaterials, 30(34), 6565–6572.

    CAS  PubMed  Google Scholar 

  68. Ofudje, E. A., Rajendran, A., Adeogun, A. I., Idowu, M. A., Kareem, S. O., & Pattanayak, D. K. (2018). Synthesis of organic derived hydroxyapatite scaffold from pig bone waste for tissue engineering applications. Advanced Powder Technology, 29(1), 1–8.

    CAS  Google Scholar 

  69. Barakat, N. A., Khalil, K., Sheikh, F. A., Omran, A., Gaihre, B., Khil, S. M., & Kim, H. Y. (2008). Physiochemical characterizations of hydroxyapatite extracted from bovine bones by three different methods: Extraction of biologically desirable HAp. Materials Science and Engineering: C, 28(8), 1381–1387.

    CAS  Google Scholar 

  70. Kusrini, E., & Sontang, M. (2012). Characterization of X-ray diffraction and electron spin resonance: Effects of sintering time and temperature on bovine hydroxyapatite. Radiation Physics and Chemistry, 81(2), 118–125.

    CAS  Google Scholar 

  71. Mezahi, F., Oudadesse, H., Harabi, A., Lucas-Girot, A., Le Gal, Y., Chaair, H., & Cathelineau, G. (2008). Dissolution kinetic and structural behaviour of natural hydroxyapatite vs. thermal treatment: Comparison to synthetic hydroxyapatite. Journal of Thermal Analysis and Calorimetry, 95(1), 21–29.

    Google Scholar 

  72. Barakat, N. A. M., Khil, M. S., Omran, A. M., Sheikh, F. A., & Kim, H. Y. (2009). Extraction of pure natural hydroxyapatite from the bovine bones bio waste by three different methods. Journal of Materials Processing Technology, 209(7), 3408–3415.

    CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Fariborz Sharifianjazi.

Ethics declarations

Conflict of Interest

All authors have participated in the (a) conception and design, or analysis and interpretation of the data; (b) drafting the article or revising it critically for important intellectual content; and (c) approval of the final version. This manuscript has not been submitted to, nor is under review at, another journal or other publishing venue. The authors have no affiliation with any organization with a direct or indirect financial interest in the subject matter discussed in the manuscript.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Esmaeilkhanian, A., Sharifianjazi, F., Abouchenari, A. et al. Synthesis and Characterization of Natural Nano-hydroxyapatite Derived from Turkey Femur-Bone Waste. Appl Biochem Biotechnol 189, 919–932 (2019). https://doi.org/10.1007/s12010-019-03046-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12010-019-03046-6

Keywords

Navigation