Development of microcarrier systems for bone tissue engineering

Download
2015
Aydoğdu, Hazal
Current strategies in bone tissue engineering have largely focused on development of carrier systems for repair and regeneration of bone tissue defects. The microcarrier systems offer an efficient method of delivery of cells with non-invasive injectable system. In this study, three-dimensional hydrogel microspheres were developed via water-in-oil emulsion method. In the first part of the thesis, porous pullulan (PULL) microspheres, with average size of 153±46 µm, were prepared and the surface of the microspheres were modified with (a) silk fibroin (SF) by reductive amination via surface oxidation of PULL microspheres, and (b) biomimetic mineralization by incubating the PULL microspheres in order to enhance the cell attachment and proliferation. The degradation analyses revealed that PULL microspheres had a slow degradation rate with 8% degradation in a two weeks’ period, which would support new bone tissue formation. Furthermore, the mechanical analysis showed that the microspheres had good mechanical properties that were enhanced significantly with the biomimetic mineralization with SBF incubation. Cell culture studies were conducted with SaOs-2 cell line and revealed that the SF coating and mineralization on the surface of PULL microspheres significantly increased the initial cell attachment and proliferation. In the second part of the thesis, urine derived mesenchymal stem cells were encapsulated in microspheres composed of oxidized PULL (oxPULL), alginate (ALG) and gelatin (GEL). The oxPULL with a degree of oxidation of 68±4%, and gelatin were crosslinked via borax catalyzed crosslinking while alginate was crosslinked with calcium and the average size for microspheres was found to be 530±32 µm. The cell culture studies indicated that the cells were successfully encapsulated, retained their viability and proliferated. According to these results, it can be suggested that the PULL microcarriers are suitable for use as injectable systems and have potential in bone tissue engineering applications.

Suggestions

Wet spun PCL scaffolds for tissue engineering
Malikmammadov, Elbay; Hasırcı, Nesrin; Endoğan Tanır, Tuğba; Department of Micro and Nanotechnology (2017)
Scaffolds produced for tissue engineering applications are promising alternatives to be used in healing and regeneration of injured tissues and organs. In this study, fibrous poly(ε-caprolactone) (PCL) scaffolds were prepared by wet spinning technique and modified by addition of β-tricalcium phosphate (β-TCP) and by immobilizing gelatin onto fibers. Meanwhile, gelatin microspheres carrying Ceftriaxone sodium (CS), a model antibiotic, were added onto the scaffolds and antimicrobial activity of CS was investi...
Polymeric scaffolds for bioactive agent delivery in bone tissue engineering
Uçar, Şeniz; Hasırcı, Nesrin; Yılgör, Pınar; Department of Chemistry (2012)
Tissue engineering is a multidisciplinary field that is rapidly emerging as a promising new approach in the restoration and reconstruction of tissues. In this approach, three dimensional (3D) scaffolds are of great importance. Scaffolds function both as supports for cell growth and depot for sustained release of required active agents (e.g. enzymes, genes, antibiotics, growth factors). Scaffolds should possess certain properties in accordance with usage conditions. Wet-spinning is a simple technique that ha...
Development and characterization of silk fibroin and citrus pectin based scaffolds for bone tissue engineering
Ataol, Sibel; Tezcaner, Ayşen; Akdağ, Akın; Department of Biomedical Engineering (2014)
Current strategies of tissue engineering aim to design and develop biologically, physicochemically and mechanically proper scaffolds. Natural polymers are gaining interest in applications since they have already many roles in biochemical pathways and have proper mechanical properties. The objective of this thesis is to develop natural silk fibroin (SF) and citrus pectin (PEC) based three-dimensional porous scaffolds for bone tissue engineering applications. Additionally, we aimed to synthesize nano calcium ...
3D Porous Composite Scaffold of PCL-PEG-PCL/Sr2+ and Mg2+ Ions Co-Doped Borate Hydroxyapatite for Bone Tissue Engineering
Yedekçi, Buşra; Evis, Zafer; Tezcaner, Ayşen; Department of Engineering Sciences (2021-9-6)
Bioceramic/polymer composite systems have gained importance in treating hard tissue damages using bone tissue engineering (BTE). In this context, it was aimed to develop 3D porous composite PCL-PEG-PCL scaffolds containing different amounts of B, Sr and Mg multi-doped hydroxyapatite (HA) that can provide bone regeneration in the bone defect area and to investigate the effect of both the amount of inorganic phase and the porosity on the mechanical and the biological properties. B-Sr-Mg multi-doped HAs were s...
Simvastatin loaded porous hydroxyapatite based microcarriers for bone tissue engineering /
Güldiken, Merve; Tezcaner, Ayşen; Durucan, Caner; Department of Biotechnology (2014)
Bone tissue engineering provides a new medical therapy as an alternative to conventional bone replacement grafts. Carriers designed for bone tissue engineering applications should be biocompatible, bioactive, and porous and should also meet certain minimal requirements to obtain functional engineered tissues. Polymers, ceramic materials and their composites are widely used for developing such carriers. The objective of this study was to develop and characterize a simvastatin (SIM) loaded porous hydroxyapati...
Citation Formats
H. Aydoğdu, “Development of microcarrier systems for bone tissue engineering,” M.S. - Master of Science, Middle East Technical University, 2015.