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Bacterial cellulose-reinforced boron-doped hydroxyapatite/gelatin scaffolds for bone tissue engineering

  • Deniz Atila
  • Ayten Karataş
  • Atilla Evcin
  • Dilek Keskin
  • Ayşen TezcanerEmail author
Original Research


Today, many people are suffering from bone defects due to trauma, tumor or bone related diseases. Mimicking bone in terms of composition and structure has been a challenge for tissue engineers. In this study, a novel 3D porous tissue-engineered construct composed of natural and easily-accessible biomaterials, namely (1) an exopolysaccharide; bacterial cellulose (BC), (2) mineral crystals; boron-doped nano-hydroxyapatite (BHA), and (3) a natural protein; gelatin (GEL) as the main constituting biomaterial was prepared by a simple and cost-effective technique; lyophilization, for bone tissue engineering applications. BC was produced by Gluconacetobacter xylinum bacteria species and hydroxyapatite (HA) and BHA were synthesized via sol–gel technique. Characterizations of GEL-BC, GEL-BC/HA, and GEL-BC/BHA scaffolds showed that they all possessed porous structure and pores became more irregular with the addition of HA or BHA. Scaffolds exhibited high water absorption, suitable degradation rate while having in vitro bioactivity with a Ca/P ratio similar to that of bone (Ca/P < 1.67). Thermo-gravimetric analysis showed that structural stability of the scaffolds was improved with the addition of HA and BHA. The porosity of scaffolds was similar (68.49–80.94%). HA and BHA-incorporation into scaffolds further improved the mechanical properties. Cell culture studies conducted with Saos-2 cell line showed that cells attached, proliferated on the GEL-BC/BHA scaffolds at a higher level demonstrating that the scaffolds were cytocompatible. ALP activity of cells seeded on GEL-BC/BHA scaffolds was statistically highest at day 14 which was also correlated with the results of intracellular calcium deposition. Thus, GEL-BC/BHA scaffolds hold potential for use in bone tissue engineering applications.

Graphic abstract


Bacterial cellulose Boron-doped nano-hydroxyapatite Gelatin Bone tissue engineering 



We also thank BIOMATEN in METU for their support to this research.

Compliance with ethical standards

Conflict of interest

The authors report no conflict of interest in this work.

Supplementary material

10570_2019_2741_MOESM1_ESM.tif (1 mb)
S1. DSC curve of the produced BC. (TIFF 1043 kb)
10570_2019_2741_MOESM2_ESM.tif (1.6 mb)
S2. TGA curves obtained under nitrogen atmosphere of GEL-BC, GEL-BC/HA, and GEL-BC/BHA scaffolds before and after crosslinking procedure. (TIFF 1661 kb)
10570_2019_2741_MOESM3_ESM.tif (806 kb)
S3. Cell number of Saos-2 cells on scaffolds seeded for ALP activity test. (‘#’ denoted the group statistically different than the others ‘β’ at the specific time point, p < 0.05). (TIFF 805 kb)
10570_2019_2741_MOESM4_ESM.tif (6 mb)
S4. Z-stack monitoring of GEL-BC/BHA scaffold after 14 days (Magnification: 20X; Depth: 45 μm). (Red PI staining: Cell nuclei. Green FITC counter-staining: Cytoskeletal elements of cells and non-specific binding of the scaffolds.) (TIFF 6173 kb)


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© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Department of Engineering SciencesMiddle East Technical UniversityAnkaraTurkey
  2. 2.Department of Molecular Biology and GeneticsIstanbul Technical UniversityIstanbulTurkey
  3. 3.Department of Materials Science and EngineeringAfyon Kocatepe UniversityAfyonkarahisarTurkey
  4. 4.BIOMATEN, Center of Excellence in Biomaterials and Tissue EngineeringMiddle East Technical UniversityAnkaraTurkey

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