Smart or intelligent materials are materials that respond to external stimuli such as light, sound, temperature, and pH by changing their structural or chemical properties.

We focus on using the response of intelligent materials to acoustic waves for varied applications including drug delivery, energy harvesting, and soft micro-robotics. Our multi-step approach is to first study the interaction mechanism of waves with these materials and optimize it through modelling. In the next step, we utilize the models to build prototypes that are tested in in vitro and in vivo setups mimicking the desired application.

For instance, we have used shape memory polymers (SMPs) to develop alternate drug-delivery approaches with improved spatial and temporal control compared to the existing solutions. We have also capitalized on ultrasound’s ability to focus on millimeter sized targets to improve upon contemporary efficiency benchmarks in energy transfer devices using piezoelectrics.

Confocal and SEM images of fibrin mesh

We are interested in understanding how acoustic waves can be used to alter the mechanical structure/behavior of soft materials inside the body. The resulting bioeffects can serve as stand-alone or combinatorial therapy in many diseases such as cancer, and thrombosis.

One of our interest areas is to look at the mechanics of fibrin and collagen mesh that forms the structural backbone in different systems such as blood clots and ECM matrix around tumors. Acoustically propelled microbubbles can induce deformation in a single fiber as well as the entire mesh and consequently affect cellular responses.  Understanding the fiber deformation at such different length scales under ultrasound can be a key to improving treatment outcomes for diseases.

Ultrasound is known to induce stable and inertial bubble cavitation at different intensities. We are interested in investigating the interaction of these different bubble behaviors with soft materials for various biomedical applications. 

An area of our research is to investigate the use of focused ultrasound-generated bubble clouds (histotripsy) for mechanical ablation of soft materials such as blood clots and tumor. Solutions are sought where histotripsy can be used as adjuvant strategy to enhance the treatment outcome of conventional drug-based approaches. Our group is developing benchtop setups to study bubble activity and its interaction with soft tissues under ultrasound image guidance.