Photoacoustic micro-viscoelastography for mapping mechanocellular properties

Cellular biomechanical properties provide essential insights into biological functions regarding health and disease. Current measurements of the biomechanical properties of cells require physical contact with cells or pre-loading on the cells. Here, we have developed photoacoustic micro-viscoelastography (PAMVE), which utilizes the phase characteristics of photoacoustic (PA) response, for mapping mechanocellular properties in a load-free manner. PAMVE realizes the local viscoelasticity measurement on the macrophages and red blood cells with micrometer scale. Furthermore, PAMVE can successfully identify the adipose cell and skeletal muscle cell due to the difference in their composition-related biomechanical properties. PAMVE represents an irreplaceable option for interrogating characteristic mechanocellular properties, opening the possibility of studying cellular mechanobiology and pathophysiology.