Two-photon polymerization of 3-D zirconium oxide hybrid scaffolds for long-term stem cell growth.

Two-photon polymerization is a technique that involves simultaneous absorption of two photons from a femtosecond laser for selective polymerization of a photosensitive material. In this study, two-photon polymerization was used for layer-by-layer fabrication of 3-D scaffolds composed of an inorganic-organic zirconium oxide hybrid material. Four types of scaffold microarchitectures were created, which exhibit layers of parallel line features at various orientations as well as pores between the line features. Long-term cell culture studies involving human bone marrow stromal cells were conducted using these 3-D scaffolds. Cellular adhesion and proliferation were demonstrated on all of the scaffold types; tissuelike structure was shown to span the pores. This study indicates that two-photon polymerization may be used to create microstructured scaffolds out of an inorganic-organic zirconium oxide hybrid material for use in 3-D tissue culture systems.