A Hybrid Miniaturized Modular Probe for Minimally Invasive Neural Intervention

Abstract Brain's unique anatomical structure and physiological environment make it difficult to deliver therapeutic agents such as drug or light to a focal volume in brain for disease treatment. Physically targeting a fine structure in brain with a micro‐neural probe is an effective solution. Here, we present a hybrid miniaturized neural probe designed with micro‐fluidic channel(s) for drug delivery, micro‐electrode(s) for neural sensing and an optical fiber for optical‐related treatment. These functional components are integrated in a micro‐cannula (diameter <300 µm) with modular design and fabrication properties which can be conveniently adjusted for diverse applications. In vitro and in vivo tests confirm that this probe can precisely deliver drug to a focal volume in brain bypassing the blood brain barrier, and on‐site neural sensing can be achieved with the integrated neural electrode. Leveraging near infrared light’s scattering properties in brain, we demonstrate in vivo with rat glioblastoma model that this hybrid neural probe can be a platform for photothermal treatment of brain tumor. With these merits, the hybrid miniaturized neural probe will be an effective tool with great translational potentials for minimally invasive neural intervention such as drug delivery or combination treatment of brain diseases.