Bone tissue generation on biodegradable polymeric scaffolds

Torun Köse, Gamze
In the present study, tissue engineered bone was produced on calcium phosphate loaded collagen and PHBV8 matrices. Osteoblasts isolated from rat bone marrow were characterized by light microscopy, alkaline phosphatase (ALP) activity, osteocalcin determination assay, and Western blots for integrin. Population doubling time of the cells was found as 50 ± 2 h at 37 °C in a CO2 incubator. PHBV8 foams iiiwere treated with rf-oxygen plasma to modify their surface chemistry and hydrophilicity to increase the reattachment of osteoblasts. Optimum power and duration was found to be 100 W 10 min. Another carrier material, lyophilized collagen foam, was loaded with calcium phosphate to mimic the composition of the bone to provide a better environment for cell proliferation and also to prevent rapid resorption of the foam. The presence of calcium phosphate and the molar ratio of calcium over phosphorus (2.26) in the collagen matrix was determined by SEM- EDS. The surface characteristics, average pore size and distribution in PHBV8 and collagen matrices were studied by SEM and Scion Image Analysis Program. Void volume and density of the foams were also found to be related to foam preparation conditions. Stability of PHBV foams in aqueous media was studied. The weight and density were unchanged for a period of 120 days but then a significant decrease was observed for the rest of the study. In order to determine the cell density of the films and the foams, MTS assay was carried out. Osteoblast growth inside the matrices was also determined by ALP and osteocalcin assays, Western blot for integrin, along with histological examinations, SEM and confocal microscopy. After 29 days of incubation, growth of osteoblasts on matrices and initiation of mineralization were observed. Large size sucrose (300-500 urn) loaded PHBV8 (6 %, w/w) foams treated with 100 W 10 min rf-plasma were found to be the most suitable matrices for osteoblast growth.


Bone response to biomimetic implants delivering BMP-2 and VEGF: An immunohistochemical study
RAMAZANOĞLU, Mustafa; Lutz, Rainer; Rusche, Philipp; Trabzon, Levent; Kose, Gamze Torun; Prechtl, Christopher; Schlegel, Karl Andreas (2013-12-01)
This animal study evaluated bone healing around titanium implant surfaces biomimetically coated with bone morphogenic protein-2 (BMP-2) and/or vascular endothelial growth factor (VEGF) by examining bone matrix proteins and mineralisation. Five different implant surfaces were established: acid-etched surface (AE), biomimetic calcium phosphate surface (CAP), BMP-2 loaded CAP surface, VEGF loaded CAP surface and dual BMP-2 + VEGF loaded CAP surface. The implants were inserted into calvariae of adult domestic p...
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Kose, GT; Korkusuz, F; Korkusuz, P; Purali, N; Ozkul, A; Hasırcı, Vasıf Nejat (2003-12-01)
Bone formation was investigated in vitro by culturing rat marrow stromal osteoblasts in biodegradable, macroporous poly(3-hydroxybutyric acid-co-3-bydroxyvaleric acid) (PHBV) matrices over a period of 60 days. Foams were prepared after solvent evaporation and solute leaching. PHBV solutions with different concentrations were prepared in chloroform: dichloromethane (1:2, v/v). In order to create a matrix with high porosity and uniform pore sizes, sieved sucrose crystals (300-500 mum) were used. PHBV foams we...
Bone tissue engineering on patterned collagen films: an in vitro study
Ber, S; Kose, GT; Hasırcı, Vasıf Nejat (2005-05-01)
This study aimed at guiding osteoblast cells from rat bone marrow on chemically modified and patterned collagen films to study the influence of pattern, on cell guidance. The films were stabilized using different treatment methods including crosslinking with carbodiimide (EDC) and glutaraldehyde, dehydrothermal treatment (DHT), and deposition of calcium phosphate on the collagen membrane.
Fabrication of functionalized citrus pectin/silk fibroin scaffolds for skin tissue engineering
Türkkan, Sibel; Atila, Deniz; Akdağ, Akın; Tezcaner, Ayşen (Wiley, 2018-10-01)
In this study, novel porous three-dimensional (3D) scaffolds from silk fibroin (SF) and functionalized (amidated and oxidized) citrus pectin (PEC) were developed for skin tissue engineering applications. Crosslinking was achieved by Schiff's reaction in borax presence as crosslinking coordinating agent and CaCl2 addition. After freeze-drying and methanol treatment, plasma treatment (10 W, 3 min) was applied to remove surface skin layer formed on scaffolds. 3D matrices had high porosity (83%) and interconnec...
Composite clinoptilolite/PCL-PEG-PCL scaffolds for bone regeneration: In vitro and in vivo evaluation
Pazarçeviren, Ahmet Engin; Altunbas, Korhan; Yaprakci, Volkan; Erdemli, Ozge; Keskin, Dilek; Tezcaner, Ayşen (Wiley, 2020-01-01)
In this study, clinoptilolite (CLN) was employed as a reinforcement in a polymer-based composite scaffold in bone tissue engineering and evaluated in vivo for the first time. Highly porous, mechanically stable, and osteogenic CLN/PCL-PEG-PCL (CLN/PCEC) scaffolds were fabricated with modified particulate leaching/compression molding technique with varying CLN contents. We hypothesized that CLN reinforcement in a composite scaffold will improve bone regeneration and promote repair. Therefore, the scaffolds we...
Citation Formats
G. Torun Köse, “Bone tissue generation on biodegradable polymeric scaffolds,” Ph.D. - Doctoral Program, Middle East Technical University, 2002.