A new peptide-based urethane polymer: synthesis, biodegradation, and potential to support cell growth in vitro
A new peptide-based urethane polymer: synthesis, biodegradation, and potential to support cell growth in vitro
- BioMaterials, 21(12), p.1247-1258, 2000 .
A novel non-toxic biodegradable lysine-di-isocyanate (LDI)-based urethane polymer was developed for use in tissue engineering applications. This matrix was synthesized with highly puri"ed LDI made from the lysine diethylester. The ethyl ester of LDI was polymerized with glycerol to form a prepolymer. LDI}glycerol prepolymer when reacted with water foamed with the liberation of CO 2 to provide a pliable spongy urethane polymer. The LDI}glycerol matrix degraded in aqueous solutions at 100, 37, 22, and 43C at a rate of 27.7, 1.8, 0.8, and 0.1 mM per 10 days, respectively. Its thermal stability in water allowed its sterilization by autoclaving. The degradation of the LDI}glycerol polymer yielded lysine, ethanol, and glycerol as breakdown products. The degradation products of LDI}glycerol polymer did not signi"cantly a!ect the pH of the solution. The glass transition temperature (¹')of this polymer was found to be 103.43C. The physical properties of the polymer network were found to be adequate to support the cell growth in vitro, as evidenced by the fact that rabbit bone marrow stromal cells (BMSC)attached to the polymer matrix and remained viable on its surface. Culture of BMSC on LDI}glycerol matrix for long durations resulted in the formation of multilayered con#uent cultures, a characteristic typical of bone cells. Furthermore, cells grown on LDI}glycerol matrix did not di!er phenotypically from the cells grown on the tissue culture polystyrene plates as assessed by the cell growth, and expression of mRNA for collagen type I, and transforming growth factor-b1 (TGF-b1). The observations suggest that biodegradable peptide-based urethane polymers can be synthesized which may pave their way for possible use in tissue engineering applications
LYSINE-DI-ISOCYANATE
GLYCEROL
URETHANE POLYMER
OSTEOBLASTS
CELL CULTURE
A novel non-toxic biodegradable lysine-di-isocyanate (LDI)-based urethane polymer was developed for use in tissue engineering applications. This matrix was synthesized with highly puri"ed LDI made from the lysine diethylester. The ethyl ester of LDI was polymerized with glycerol to form a prepolymer. LDI}glycerol prepolymer when reacted with water foamed with the liberation of CO 2 to provide a pliable spongy urethane polymer. The LDI}glycerol matrix degraded in aqueous solutions at 100, 37, 22, and 43C at a rate of 27.7, 1.8, 0.8, and 0.1 mM per 10 days, respectively. Its thermal stability in water allowed its sterilization by autoclaving. The degradation of the LDI}glycerol polymer yielded lysine, ethanol, and glycerol as breakdown products. The degradation products of LDI}glycerol polymer did not signi"cantly a!ect the pH of the solution. The glass transition temperature (¹')of this polymer was found to be 103.43C. The physical properties of the polymer network were found to be adequate to support the cell growth in vitro, as evidenced by the fact that rabbit bone marrow stromal cells (BMSC)attached to the polymer matrix and remained viable on its surface. Culture of BMSC on LDI}glycerol matrix for long durations resulted in the formation of multilayered con#uent cultures, a characteristic typical of bone cells. Furthermore, cells grown on LDI}glycerol matrix did not di!er phenotypically from the cells grown on the tissue culture polystyrene plates as assessed by the cell growth, and expression of mRNA for collagen type I, and transforming growth factor-b1 (TGF-b1). The observations suggest that biodegradable peptide-based urethane polymers can be synthesized which may pave their way for possible use in tissue engineering applications
LYSINE-DI-ISOCYANATE
GLYCEROL
URETHANE POLYMER
OSTEOBLASTS
CELL CULTURE