A preliminary study of acoustic propagation in thick foam tissue scaffolds composed of poly(lactic-co-glycolic acid)

The exclusive ability of acoustic waves to probe the structural, mechanical and fluidic properties of foams may offer novel approaches to characterise the porous scaffolds employed in tissue engineering. Motivated by this we conduct a preliminary investigation into the acoustic properties of a typical biopolymer and the feasibility of acoustic propagation within a foam scaffold thereof. Focussing on poly(lactic-co-glycolic acid), we use a pulse-echo method to determine the longitudinal speed of sound, whose temperature-dependence reveals the glass transition of the polymer. Finally, we demonstrate the first topographic and tomographic acoustic images of polymer foam tissue scaffolds.