Combination of in vitro thermally-accelerated ageing and Fourier-Transform Infrared spectroscopy to predict scaffold lifetime

Biodegradable elastomers face a growing use in soft tissue engineering due to the possibility to tune, by an appropriate selection of the synthesis and process conditions, the material thermo-mechanical properties to match the stress-strain behavior of the tissue to replace. However, changes in material properties can impact drastically the scaffold durability and therefore the efficiency of tissue reconstruction. Few studies focus on approaches allowing the prediction of the scaffold lifetime, while there is a need for strategies using accelerated testing protocols and versatile tools to easily investigate on the material degradation rate. In the present study, elastomeric cross-linked poly(ester-urethane-urea) scaffolds have been developed through an emulsion technique allowing to produce highly interconnected porous structure. Thermally-accelerated ageing was performed in cell culture medium at different temperatures: 37 degrees C, 55 degrees C, 75 degrees C and 90 degrees C. The degradation process was followed by gravimetry, swelling measurements, compression tests and infrared spectroscopy. The study revealed that the scaffold chemical composition variation was temperature dependant and its analysis by Fourier-Transform infrared spectroscopy allowed an easy de-termination of the activation energy of the hydrolytic degradation process, leading to the prediction of the scaffold lifetime at 37 degrees C using Arrhenius extrapolation. This approach could be used to simply and straightforwardly screen the durability of new scaffolds. (C) 2020 Elsevier Ltd. All rights reserved.