Acoustic method for permeability measurement of tissue engineering scaffold

An accurate intrinsic permeability measurement system has been designed and realized in order to quantify the inter-pore connectivity structure of tissue-engineering scaffolds by using a single (pressure) transducer. The proposed method uses a slow alternating airflow as a fluid medium and allows at the same time a simple and accurate measurement procedure. The intrinsic permeability is determined in the linear Darcy's region, and deviation from linearity due to inertial losses is also quantified. The structural parameters of a scaffold, such as effective porosity, tortuosity and effective length of cylindrical pores, are estimated using the classical Ergun's equation recently modified by Wu et al. From this relation, it is possible to achieve a well-defined range of data and associated uncertainties for characterizing the structure/architecture of tissue-engineering scaffolds. This quantitative analysis is of paramount importance in tissue engineering, where scaffold topological features are strongly related to their biological performance.