Spatial and temporal control of shape memory polymers and simultaneous drug release using high intensity focused ultrasound

In this paper, we report a new modality enabling the simultaneous control of shape memory polymers (SMPs) and release of loaded drugs. The approach uses high intensity focused ultrasound (HIFU) and explores localized heating of SMPs upon HIFU exposure. We show that the HIFU-triggered shape recovery process can be spatially and temporarily controlled, allowing the shape memory effect to manifest in selected regions on demand, endowing SMPs with the capability of adopting multiple intermediate shapes and synchronizing the release of loaded drugs in a switchable manner. To our knowledge, this is the first time that HIFU is utilized as a trigger to reveal these appealing features of SMPs.