Department of Convergence IT Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 37673, Republic of Korea.
Electrical Engineering Division, Department of Engineering, University of Cambridge, 9 JJ Thomson Ave, Cambridge, CB3 0FA, UK.
Adv Mater. 2023 Sep;35(38):e2301782. doi: 10.1002/adma.202301782. Epub 2023 Jul 19.
Neural recording systems have significantly progressed to provide an advanced understanding and treatment for neurological diseases. Flexible transistor-based active neural probes exhibit great potential in electrophysiology applications due to their intrinsic amplification capability and tissue-compliant nature. However, most current active neural probes exhibit bulky back-end connectivity since the output is current, and the development of an integrated circuit for voltage output is crucial for near-sensor signal processing at the abiotic/biotic interface. Here, inkjet-printed organic voltage amplifiers are presented by monolithically integrating organic electrochemical transistors and thin-film polymer resistors on a single, highly flexible substrate for in vivo brain activity recording. Additive inkjet printing enables the seamless integration of multiple active and passive components on the somatosensory cortex, leading to significant noise reduction over the externally connected typical configuration. It also facilitates fine-tuning of the voltage amplification and frequency properties. The organic voltage amplifiers are validated as electrocorticography devices in a rat in vivo model, showing their ability to record local field potentials in an experimental model of spontaneous and epileptiform activity. These results bring organic active neural probes to the forefront in applications where efficient sensory data processing is performed at sensor endpoints.
神经记录系统取得了显著进展，为神经疾病的研究和治疗提供了更深入的了解。基于晶体管的柔性神经探针由于其固有的放大能力和与组织相适应的特性，在电生理学应用中具有很大的潜力。然而，由于大多数当前的主动神经探针的输出为电流，因此后端连接较为庞大，而开发用于电压输出的集成电路对于在非生物/生物界面进行近传感器信号处理至关重要。在这里，通过在单个高度灵活的衬底上单片集成有机电化学晶体管和薄膜聚合物电阻器，提出了喷墨打印有机电压放大器，用于在体脑活动记录。添加剂喷墨打印可实现多个有源和无源组件在体感觉皮层上的无缝集成，与外部连接的典型配置相比，显著降低了噪声。它还便于对电压放大和频率特性进行微调。在大鼠体内模型中，有机电压放大器被验证为脑皮层电图设备，可记录自发和癫痫样活动实验模型中的局部场电位。这些结果使有机有源神经探针在需要在传感器端点进行高效感测数据处理的应用中处于领先地位。
