NOVEL FABRICATION AND CHARACTERIZATION OF PORE-SIZE-GRADIENT SCAFFOLDS BY A CENTRIFUGATION TECHNIQUE - Intelligent Scaffolds for Tissue Engineering and Regenerative Medicine - page 606

optimal pore sizes for bone ingrowth and regeneration are highly
dependent on pore structures as well as scaffold materials used.
30.4 Conclusions
We fabricated cylindrical scaffolds with gradually increasing pore
size along the longitudinal direction by the centrifugation method.
The pore size (or porosity) of the scaffolds increased along the
cylindrical axis by the gradual increment of the centrifugal force.
The prepared alginate, chitosan, and PCL scaffolds had the pore size
(porosity) rangesalongthecylindricalaxisfrom80 ∼ 88 μ mto 310
∼ 405 μ m (from 80% ∼ 83% to 93% ∼ 94%), as the centrifugal
speedof3,000rpmwasapplied.Fromthe in vitro cellculture(chon-
drocytes,osteoblasts,andfibroblasts)and in vivo animalstudy(rab-
bit cranial defect model), it was observed that the cells and tissues
were shown to have different pore size ranges in the scaffolds for
effective cell growth and tissue regeneration: ∼ 400 μ m pore size
for chondrocytes and osteoblasts, ∼ 200 μ m pore size for fibroblast
growth, and ∼ 310 μ m pore size for new bone formation. The pore-
size-gradient scaffolds fabricated by the centrifugation method can
beagoodtoolforthesystematicstudiesoftheinteractionsbetween
cells or tissuesand scaffoldswith different pore sizes.
Acknowledgments
This work was supported by a grant from the Korea Research Foun-
dation (KRF-2003-041-D00212).
References
1. T. S. Karande, J. L. Ong, and C. M. Agrawal, Ann. Biomed. Eng ., 32 , 1728
(2004).
2. H. Shin, S. Jo, and A. G. Mikos, Biomaterials , 24 ,4353 (2003).
3. B. D. Ratnerand S. J. Bryant, Ann. Rev. Biomed. Eng ., 6 ,41, (2004).
4. S. Wang, W. Cui, and J. Bei, Anal. Bioanal. Chem ., 381 ,547 (2005).