Laser microstructured 3D polymeric biocompatible implants

In this report we present experimental results on biocompatibility based on stem cell growth experiments in vitro as well as reaction of living organism to polymer implants in vivo of femtosecond laser 3D micro/nanostructurable photopolymers. A synergetic study on materials for rapid 3D scaffold fabrication having micrometer features and being centimeter in size, their biocompatibility in vitro and in vivo was done. The systematic study was performed providing consistent information which is important for further progress in cell growth and tissue engineering experiments. The chosen materials where of four different classes: well known biocompatible hybrid ORMOCER (Ormocore b59, Micro Resist) [1], widely used biodegradable di-acrylated poly(ethylene)glycol (PEG-DA-258, Sigma-Aldrich) [2], pure acrylate AKRE (SR368, Sartomer) [3] and novel high quality laser structurable material ORMOSIL (SZ2080, FORTH) [4]. All of the materials were evaluated by their suitability for femtosecond laser structuring, which is well established as a technique enabling rapid and flexible production of 3D micro/nanostructures. All photopolymers could be 3D structured with < 1 µm resolution and up to cm in overall sizes, thus materializing the computer models of the scaffolds with required pore sizes and porosities. The typical dimensions of scaffolds were 5 × 5 × 0.5 mm3 discs with 25 µm pore sizes and 40–60% porosity.