Temperature sweep characterization of gelatin via inertial microcavitation rheometry

The interaction of ~mJ focused laser energy pulses and soft, bio-relevant hydrogels and resins is complex, including plasma formation, ultra-fast bubble expansion and collapse called inertial cavitation, and heat-and-mass transfer physics. Fortunately, a century of fluid dynamics advances has helped illuminate the important aspects of this process in a model, which we can combine with experiments to optically characterize the viscoelastic mechanical behavior of these soft materials at high rates. We highlight this technique, called Inertial Microcavitation Rheology, in a variety of scenarios including over varied gel composition, laser energies, bubble stretch ratios. We further suggest some approaches toward maximizing applicability by taking a parsimonious approach to assessing material behavior based on experimental observables.