Sequential growth factor delivery from complexed microspheres for bone tissue engineering

Basmanav, F. Buket
Hasırcı, Vasıf Nejat
Aim of the study was to design a 3D tissue-engineering scaffold capable of sequentially delivering two bone morphogenetic proteins (BMP). The novel delivery system consisted of microspheres of polyelectrolyte complexes of poly(4-vinyl pyridine) (P4VN) and alginic acid loaded with the growth factors BMP-2 and BMP-7 which themselves were loaded into the scaffolds constructed of PLGA. Microspheres carrying the growth factors were prepared using polyelectrolyte solutions with different concentrations (4-10%) to control the growth factor release rate. Release kinetics was studied using albumin as the model drug and the populations that release their contents very early and very late in the release study were selected to carry BMP-2 and BMP-7, respectively. Foam porosity changed when the microspheres were loaded. Bone marrow derived stem cells (BMSC) from rats were seeded into these foams. Alkaline phosphatase (ALP) activities were found to be lowest and cell proliferation was highest at all time points with foams carrying both the microsphere populations, regardless of BMP presence. With the present doses used neither BMP-2 nor BMP-7 delivery had any direct effect on proliferation, however, they enhanced osteogenic differentiation. Co-administration of BMP enhanced osteogenic differentiation to a higher degree than with their single administration.


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Yilgor, P.; Hasırcı, Nesrin; Hasırcı, Vasıf Nejat (2010-05-01)
The aim of this study was to develop a nanosized, controlled growth factor release system to incorporate into tissue engineering scaffolds and thus activate the cells seeded in the scaffold. Nanocapsules of poly(lactic acid-co-glycolic acid) (PLGA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) were loaded with the bone morphogenetic proteins BMP-2 and BMP-7, respectively, and with bovine serum albumin (BSA), the model protein. BSA-loading efficiency and release kinetics were used to determine the ...
Dynamic cell culturing and its application to micropatterned, elastin-like protein-modified poly(N-isopropylacrylamide) scaffolds
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In this study a tissue engineering scaffold was constructed from poly(N-isopropylacrylamide) (pNIPAM) to study the influence of strain on cell proliferation and differentiation. The effect of surface chemistry and topography on bone marrow mesenchymal stem cells was also investigated. Micropatterned pNIPAM films (channels with 10 mu m groove width, 2 mu m ridge width, 20 mu m depth) were prepared by photo-polymerization. The films were chemically modified by adsorption of a genetically engineered and temper...
Incorporation of a sequential BMP-2/BMP-7 delivery system into chitosan-based scaffolds for bone tissue engineering
Yilgor, Pinar; Tuzlakoglu, Kadriye; Reis, Rui L.; Hasırcı, Nesrin; Hasırcı, Vasıf Nejat (2009-07-01)
The aim of this study was to develop a 3-D construct carrying an inherent sequential growth factor delivery system. Poly(lactic acid-co-glycolic acid) (PLGA) nanocapsules loaded with bone morphogenetic protein BMP-2 and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanocapsules loaded with BIVIP-7 made the early release of BMP-2 and longer term release of BMP-7 possible. 3-D fiber mesh scaffolds were prepared from chitosan and from chitosan-PEO by wet spinning. Chitosan of 4% concentration in 2% aceti...
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Altay, Gizem; Hasırcı, Vasıf Nejat; Khademhosseini, Ali; Department of Biomedical Engineering (2011)
In this study we fabricated free standing multilayer films of polyelectrolyte complexes for potential use in tissue engineering of corneal stroma by using the layer-by-layer (LbL) approach. In the formation of these LbL films negatively charged, photocrosslinkable (methacrylated) hyaluronic acid (MA-HA) was used along with polycations polyethyleneimine (PEI) and poly(L-lysine) (PLL). Type I collagen (Col) was blended in with PLL for improving the water absorption and cell attachment properties of the films....
Silicate-doped nano-hydroxyapatite/graphene oxide composite reinforced fibrous scaffolds for bone tissue engineering
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In this study, novel graphene oxide-incorporated silicate-doped nano-hydroxyapatite composites were prepared and their potential use for bone tissue engineering was investigated by developing an electrospun poly(epsilon-caprolactone) scaffold. Nanocomposite groups were synthesized to have two different ratios of graphene oxide (2 and 4 wt%) to evaluate the effect of graphene oxide incorporation and groups with different silicate-doped nano-hydroxyapatite content was prepared to investigate optimum concentra...
Citation Formats
F. B. Basmanav, G. KÖSE, and V. N. Hasırcı, “Sequential growth factor delivery from complexed microspheres for bone tissue engineering,” BIOMATERIALS, pp. 4195–4204, 2008, Accessed: 00, 2020. [Online]. Available: