Injectable 2D Material‐Based Sensor Array for Minimally Invasive Neural Implants

Intracranial implants for diagnosis and treatment of brain diseases have been developed over the past few decades. However, the platform of conventional implantable devices still relies on invasive probes and bulky sensors in conjunction with large‐area craniotomy and provides only limited biometric information. Here, an implantable multi‐modal sensor array that can be injected through a small hole in the skull and inherently spread out for conformal contact with the cortical surface is reported. The injectable sensor array, composed of graphene multi‐channel electrodes for neural recording and electrical stimulation and MoS2‐based sensors for monitoring intracranial temperature and pressure, is designed based on a mesh structure whose elastic restoring force enables the contracted device to spread out. It is demonstrated that the sensor array injected into a rabbit's head can detect epileptic discharges on the surface of the cortex and mitigate it by electrical stimulation while monitoring both intracranial temperature and pressure. This method provides good potential for implanting a variety of functional devices via minimally invasive surgery. A graphene and MoS2‐based implantable multi‐modal sensor array is developed, presenting a minimally invasive implantation process for neural monitoring apparatus. The sensor array is injected via syringe and air pressure through a small hole in the skull and spreads out to conformally cover the cortical surface. The sensors detect epileptic discharges and monitor intracranial temperature and pressure.