USE OF AN ACOUSTIC METHOD FOR THE EVALUATION OF SCAFFOLD TRANSPORT PROPERTIES IN BONE TISSUE ENGINEERING

Aim: Transport phenomena characterize the effectiveness of scaffolds for tissue engineering (TE), because transport properties are strictly related to, e.g., uptake of oxygen and nutrients in depth, scaffold colonization by cultured cells. An important feature affecting transport in a scaffold is permeability. In fact, permeability is an effective parameter in (a) estimating mass and species transport through the scaffold and (b) describing its topological features, thus allowing a better evaluation of the scaffold biological performance. Artificial scaffolds should be designed in order to have transport properties similar to the natural tissue they are supposed to mimic. Methods: To support the design of bone TE scaffolds, here we use an ad hoc test bench to measure the intrinsic permeability of an artificial scaffold for bone tissue engineering and we compare it to a natural sample of cancellous bone of animal origin. The test bench allows for intrinsic permeability measurement using a slow alternating airflow as a fluid medium and a calibrated low-frequency pressure field capacitive microphone. For this study we used: (a) an artificial ceramic scaffold, and (b) a natural cancellous bone sample. Results: The intrinsic permeability of the scaffold was effectively measured with a confidence level of 95%. Conclusions: The application of the airflow-based system proposed could lead to reproducible, repeatable and accurate experimental data, thus producing an improvement of the structural/architectural characterization of the bone tissue-engineering scaffolds under investigation.