Microtubular architecture of biodegradable polymer scaffolds

It is a relatively new approach to generate tissues with mammalian cells an d scaffolds (temporary synthetic extracellular matrices). Many tissues, suc h as nerve, muscle, tendon, ligament, blood vessel, bone, and teeth, have t ubular or fibrous bundle architectures and anisotropic properties. In this work, we have designed and fabricated highly porous scaffolds from biodegra dable polymers with a novel phase-separation technique to generate controll able parallel array of microtubular architecture. Porosity as high as 97% h as been achieved. The porosity, diameter of the microtubules, the tubular m orphology, and their orientation are controlled by the polymer concentratio n, solvent system, and temperature gradient. The mechanical properties of t hese scaffolds are anisotropic. Osteoprogenitor cells are seeded in these t hree-dimensional scaffolds and cultured in vitro. The cell distribution and the neo-tissue organization are guided by the microtubular architecture. T he fabrication technique can be applied to a variety of polymers, therefore the degradation rate and cell-matrix interactions can be controlled by the chemical composition of the polymers and the incorporation of bioactive mo ieties. These microtubular scaffolds may be used to engineer a variety of t issues with anisotropic architecture and properties. (C) 2001 John Wiley & Sons, Inc.