整合光鉗系統與生物相容性微電極陣列晶片進行神經細胞刺激與神經信號記錄

Abstract

神經科學是一門複雜且奧妙的學問，尤其神經中樞-大腦更是眾多學者致力研究的 目標，如何運用適當的儀器及技術剖析大腦精細的運作功能成為極具挑戰性且富含研究 價值的工作。研究人員為了簡化複雜的神經網路，使用少量的神經細胞建構研究模型以 深入探討化學性或物理性刺激對於細胞間的相互影響，而使用電生理技術透過離體觀察 一群神經細胞的活動變化成為可行方案。藉由多個電極分佈於細胞培養的基材或培養皿 可進行多通道神經元的高頻動作電位與低頻場電位活動記錄，此技術可以延伸應用於非 接觸性的細胞調控或外來刺激對於神經分化與成長變化之研究。 為了建構適合細胞培養的環境，本計畫預計使用生醫微機電與表面改質技術製作具 高生物相容性的微電極陣列晶片以提供多通道與長時間記錄神經細胞活動的功能。同 時，我們整合晶片與可程式化微刺激器提供雙極性交流電刺激神經細胞或直流電場驅動 細胞遷移，透過高資料量處理之神經信號擷取系統進行即時動作電位辨識，用以研究活 體細胞神經網路。 本計畫另一個重點為提供光鉗系統進行細胞微操控的平台驗證，藉此可瞭解光、電 刺激下如何影響細胞進行分化和引導生長。首先，細胞生長於微電極陣列晶片並接受雷 射牽引進行調控，再利用後端記錄處理系統比較細胞接受光引導或光刺激前後的電生理 信號改變並作適當的處理分析。雷射牽引技術除了提升細胞操控的精確性之外，結合本 計畫所開發之微電極陣列晶片將成為研究細胞間或神經網路間相互影響之重要工具。

Understanding the interplay of neuronal cells within small, yet complex networks invitro could thus improve the predictability of physical or drug effects in the intact organism. Electrophysiological recording techniques suitable to monitor the activity of neuronal populations in vitro have recently become available. These multi-electrode tools record spike activity and low frequency potentials with substrate integrated electrodes at several sites in the dish. Besides, they facilitate collection of the sample sizes necessary for statistics. The possibility to uncontact manipulation or stimulation on the neuron further expands the range of applications and bioassays, and may thus facilitate the evaluation of neuronal differentiation and growth. For culturing cells that maintains their health, we will achieve the biocompatible multi-channel electrode array (MEA) chip based on BIO-MEMS-technology to monitor many neurons simultaneously and chronically. Furthermore, we will setup a high throughput signal acquisition/processing system with integrating the programming micro-stimulation and design an automated spike sorting algorithm to investigate the live neural network properties. The aim of this project is to provide a demonstration of the micromanipulation by optical tweezers and investigate optical, electrical stimulating guiding effects on differentiation and growth of neuron. The cells will tested on a MEA on the viewing surface of a microscope, and the laser light will guide or manipulate them through the microscope’s viewing piece. The pattern and rate of process outgrowth for manipulated cells will comparable to unmanipulated cells. MEA system will provide electrophysiological recording related to laser guidance. Optical tweezers, therefore, provide a benign technique with which to micro-manipulate whole neurons. The procedures also bestow increased precision to the study of cell-cell interactions by allowing the selection of potentially interacting cell types at a single cell level or neural networks that resemble structures in the brain.