Bi-layer PCL/PLA scaffold prepared by melt for interface tissue engineering

The development of porous multilayer devices allow controlling chemical, physical and mechanical properties by tuning the properties of each single layer. For instance, this feature is of main concern for the production of porous devices designed to regenerate diseased zones at the interface of tissue presenting intrinsic anisotropic structures that gradually change from one tissue to another. In this context, synthetic biodegradable polymers commonly used biomedical applications include polylactic acid (PLA) and polycaprolactone (PCL). In this work, a novel bi-layered multiphasic scaffold (BLS) is presented. It is composed by a PLA-layer presenting pore size in the range of 90-110 μm while the other layer was made of PCL with pores ranging from 5 to 40 μm. The sponges were prepared by combining melt mixing and particulate leaching. In brief, PLA or PCL with PEG and NaCl were fed to a batch mixer and processed until a constant value of torque was achieved. The blends were then compression molded in a laboratory press in appropriate cylindrical molds. Finally, the porogen parts of the blends (NaCl and PEG) were removed by selective leaching in demineralized water. BLS have been characterized from a morphological and a mechanical point of view. Fibroblasts and osteoblasts were cultured and co-cultured in order to investigate the cells permeation trough the different layers.