A procedure for slicing and characterizing soft heterogeneous and irregular-shaped tissue

This paper presents a slicing technique useful to prepare precise and repeatable samples from organs which are irregularly shaped and highly heterogeneous for mechanical testing and advanced microscopy observation. The suggested technique does not seem to influence the internal microstructure and it is employed here for testing specimens cut from different region of the meniscal tissue. Fast Fourier Transform analysis is used to quantify characteristic features of the microstructure (collagen fibers orientation, pore size) after slicing prior mechanical testing. Uniaxial (relaxation) tests are performed on dogbone meniscal samples. Stress relaxation testing results on samples cut from different regions of the meniscus highlights a significant scatter in the maximum stress even though the preferential collagen fibers orientation is not too dissimilar. The proposed slicing method, which requires inexpensive tools and allows to minimize sample preparation, is proved to be applicable for a range of applications from macroscopic/nano mechanical testing to microscopy observations to accurately characterize location-dependent microstructural features and mechanical properties. (C) 2020 Elsevier Ltd. All rights reserved.