■邀請加拿大蒙特羅理工學院Prof. Mohamad Sawan來訪進行演講及學術交流
演講時間：2017.09.18 上午 10:00-13:00
Title of Talk：
Brain-Microsystem Interfaces for the Diagnostic and Treatment of Neurodegenerative Diseases
Prof. Mohamad Sawan
Polytechnique Montréal, Canada
Abstract of Talk：
Implantable biosensors intended for the diagnosis and subsequent treatment of neurodegenerative diseases are emerging alternatives to study neural activities at various levels. These biosensors are being built to accelerate the understanding of cognitive functions and pathologies, and eventually to recover lost neural vital functions. This talk covers circuit techniques and Microsystems intended to build brain-microsystem interfaces for intracortical neurorecording and neurostimulation, and as both neural cell and neurotransmission categories. The implementation of custom Lab-on-chip (LoC) based devices requires dealing with multidimensional design challenges such as power management, low-power circuit design, high-data rate communication, and reliable wireless energy recovery, and encapsulation. Also, application-specific building blocks such as RF front-end, AC-DC and DC-DC Converters, Active rectifiers, Adaptive thresholders, Compressive sampling modules, Modulators & demodulators, implemented in various CMOS submicron technologies, will be discussed and experimental results will be shown. Case studies of continuous neurorecording intended for learning about the neurodegenerative diseases such as vision and epileptic seizures mechanisms will be described. In addition, microstimulation in the primary visual cortex intended to recover vision for the blind will be reported.
Proposed LoC based biosensors are used to manipulate and detect neurotransmitters, also characterization intended to locate dysfunctions at the level of neural cells interconnections will be summarized. Specific biosensors, built around ISFET platform, or based on capacitive sensing, or again they use a hybrid platform combining both techniques, will be described, altogether with techniques of cells manipulation, which are achieved through integrated on chip Dielectrophoresis or magnetophoresis methods. A CMOS-Based Smart Petri dish system for label-free monitoring of adherent mammalian cells activities. This system consists of an array of 8x8 capacitive sensors incorporated with a CMOS fully integrated readout circuit. The proposed re-configurable readout circuit allows the tracking of cellular activities using various initial cell concentrations ranging from 10 to 200 kcells/ml. For this purpose, we developed a new polyelectrolyte encapsulation method for enhancing cell-CMOS biocompatibility. Given the fact that this encapsulation method improves the cell viability; the proposed low-cost biosensor can measure the capacitance changes affected by cellular activities for more than three consecutive days using different cell lines such as human embryonic kidney cells, and human lung carcinoma cells. In this later work, we demonstrated the advantage of the proposed system for drug cytotoxicity as well as cellular growth monitoring purposes.