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Tissue Engineering and Regenerative Medicine, Vol. 1, No. 2, pp 164-170 (2004)
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Fabrication and Characterization of Pore Size Gradient Alginate
Scaffold by a Centrifugation Method
Il Kyu Park, Se Heang Oh and Jin Ho Lee*
Department of Polymer Science and Engineering, Hannam University, 133 Ojeong Dong,
Daedeog Gu, Daejeon 306-791, Korea
(Received Oct. 11, 2004; Accepted Oct. 15, 2004)
Abstract: It is well recognized that the pore size of scaffolds plays an important role for tissue ingrowth and regeneration: different kinds of cells were shown to have different optimal pore size ranges in the scaffolds for effective
cell growth. So, if the tissue scaffold with pore size gradient (i. e., the scaffold with gradually increasing pore sizes
along one direction) can be prepared, it will be of particular interest for basic studies of the interaction between tissue
cells and scaffolds since the effect of pore size can be examined in a single experiment using one scaffold (pore size
gradient scaffold). In recent years, several techniques have been used to fabricate porous polymer scaffolds having
3-dimensional pore structure. However, it is not possible to fabricate scaffolds with pore size gradient from those
techniques. In this study, we developed a new method to fabricate pore size gradient scaffolds by a simple centrifugation. We fabricated alginate cylindrical scaffolds with gradually increasing pore size (80~310 µm) along the longitudinal direction by the centrifugation method. In this method, the pore size ranges of the scaffold could be easily
controlled by adjusting centrifugal force. The prepared alginate scaffolds were impregnated into 1 wt% chitosan
solution to improve cell adhesiveness as well as mechanical strengths. This study demonstrate that the centrifugation
method is a simple and effective method to prepare tissue scaffolds with controllable pore size ranges.
Key words: Tissue engineering, alginate scaffold, pore size gradient, centrifugation method
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