Graphene based Electrical Interface for Cells

点击翻译按钮获取中文摘要

Unicellular organisms such as Yeast cells contain the complete assembly of life processes in a micron scale space. The complexity and the variety of cellular processes present in this confined space provide opportunities for development of cell based sensors and devices where the cell forms the active element for sensing. The sensing is based on observing the cells response to the administered stimuli. The advantages of the cell based sensors lie in their ability to respond to multiple stimuli, both chemical and biological in nature. For example, in most cases of security assessment the threat is unknown, hence cell based sensors will provide an evaluation of such hazards which are difficult to gauge with specific point of use type sensors. Our program aims to translate cells response into electrical signals using graphene sheets. The coupling of the sheets with the cells will be achieved using bio-compatible chemical species. The sheets with their large surface area will form an electrical conducting pathway on the cell surface. The cell below the sheets will serve as a biological gate that will modulate the flow of charge carriers in the sheets due to two primary effects: 1. Exchange of ions between the cell and its surroundings and 2. The changes in cell volume, shape and surface stresses. As real time response from the cell will be observed, its quantification will enable the identification of both the threat and also its effect on the cell. Future capabilities will be expanded to study effect of therapeutic molecules. The use of cells as sensing element will also be developed into specific point of care sensors. This is based on genetic engineering that allows the expression of particular receptors on cell surfaces that target specific specie, leading to the potential development of an array of sensors for point of use. Cell based biosensors are promising for application in multiple fields such as environmental monitoring, bio-security, pathogen and toxin screening, food industry, drug discovery and pharmacology. Commercial products have been developed using these sensors. The rapidly growing market for bio-sensors (more than $8 billion currently) will benefit from development of these sensors and their applications.