POLYURETHANE COMPOSITE FOAMS WITH CALCITE FOR BONE TISSUES CULTURES

The main function of a tissue engineering scaffolds is to act as a substrate for depozition of cells, and their subsequent growth and proliferation. The basic requirements for the scaffold material are biocompatibility, degradability, mechanical integrity and osteoconductivity. Novel biodegradable scaffolds made of poly (epsilon-caprolactone) urethane (PCL_PUR) porous matrix and calcite were developed and studied for bone tissue engineering. The scaffolds were prepared by in situ polymerization. Porous structure of the scaffolds was obtained by combining leaching and coagulation techniques, using NaCl with the grain size 250 divided by 500 mu m as a porogen. An influence of solution concentration on scaffolds structure and properties was evaluated. The structure and properties of scaffolds were studied by scanning electron microscopy. The scaffolds were incubated in a buffered simulated body fluid (SBF) at 37 degrees C for certain periods of time to allow for apatite formation and potential improvement of osteoconductivity. Calcium phosphates formation of the apatite layer on three dimensional scaffolds was investigated by Scanning Electron Microscope (SEM) equipped with Energy-Dispersive Spectrometer (EDS) and Fourier transformed infrared spectroscopy-attenuated total reflectance (FTIR-ATR). The in vitro research showed the highest biocompatibility of the PUR/ calcite composite, which was confirmed by the mole Ca/P ratio of the apatite layer on the scaffolds' surface. The mechanical properties of composites were investigated using Dynamic Mechanical Analysis (DMA). Porsity of the scaffolds were investigated with Archimedes method. The viability of cell was performed with commercial test.