Cavitation Rheology of Biological Materials

The overall physical properties of complex soft materials and tissues emerge in a complex manner from the properties of the component materials across multiple length scales ranging from nanometres to millimetres. Cavitation rheology (CR) has been used to characterise the mechanical properties of strong materials made from proteins and also cells within cell spheroids (a tumour model). I will discuss the formation and characterisation using CR of protein bigels which are stretchable hydrogels with large fracture energies formed from two interpenetrating but discrete protein networks [1]. I will then discuss how CR can be used to measure the interfacial properties and the elastic modulus of spheroids formed from HEK cells. By comparing the work of bubble formation with deformation of the cell spheroid at different length scales, the cortical tension for cells within a cell spheroid has been estimated [2].