Impulse acoustic microscopy for regenerative medicine material investigation

The aim of this paper is to presents the results of an experimental study of the possibilities of using pulsed acoustic microscopy for noninvasive characterization of materials and tissue engineering objects. The features of visualization by acoustic methods of a non-woven matrix made of thin polysulfone fibers with diameter 4-8 microns as well as a non-woven material based on chitosan with fiber diameter 100-400 nm were studied. To display small-sized cylindrical elements of the structure of matrixes - polymer fibers and strands, collagen fibers of natural tissues, an ultramicroscopic regime based on recording scattered radiation was used. Ultrasonic methods for observing the bulk microstructure of natural extracellular matrix obtained by removing cellular contents from donor organs are proposed. To display the distribution of small-scale structural elements in the cross sections of tissue matrix samples, imaging techniques are developed with the use of dynamic focusing within the object and subsequent halftone mapping of the structure-the B/D (brightness-depth) technique. The results of the research make it possible to characterize the bulk architecture of materials used in regenerative medicine.