3D Mesoporous Electrodes Integrated with Soft Surgical Robotics for Putative Minimally Invasive Intraoperative Tumor Detection and Ablation Monitoring

Flexible endoscopes equipped with multimodal sensors offer an innovative minimally invasive approach to perioperative diagnosis and intraoperative ablation monitoring, addressing the limitations of conventional mechanical- and optical-based techniques. Over the years, various miniaturized sensors have been developed, providing essential insights through minimally invasive surgeries (MIS). Among them, tactile sensors hold significant potential to revolutionize the diagnosis of tissue malignancy, serving to detect differences in the mechanical properties between healthy and cancerous tissues. However, such differences are largely detectable only at late-stage malignancy. Sensing tissue electrical properties, such as bioelectrical impedance, offers a potentially better approach to distinguishing tissue abnormalities due to the pronounced differences between divergent tissues and over the course of tumor development. Nonetheless, the integration of impedance sensors with soft medical robots remains under explored due to the challenges in fabricating suitable electrode materials that offer low interfacial impedance when in contact with biotissues. This work developed a 3D conformal electronic device based on mesoporous gold (mAu) sensors, combining top-down lithography, bottom-up electrochemical deposition, and a liquid-assisted transfer printing technique. The mAu electrode platform exhibited an enhancement in impedance sensitivity of 2.5 times higher than that of flat gold, and the 3D configuration enables tissue impedance measurements on different sides of the device, highly beneficial for navigating soft robots and performing in situ diagnosis in hard-to-reach areas. In vitro human tissue studies confirmed that the sensors can distinguish cancerous from healthy tissues. These findings highlight the potential of 3D conformal mesoporous electronics for use in advanced soft robot-assisted minimally invasive procedures.