Integration of Biomaterials in Micro/Nano Systems for
Biological and Chemical Sensing.
Reza Ghodssi
Herbert Rabin Distinguished Professor,
Director, Institute for Systems Research and MEMS Sensors and Actuators Laboratory,
Electrical and Computer Engineering Department,
University of Maryland College Park, USA
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Integration of biological materials in micro/nano systems confers multiple advantages for biosensing. Biological materials not only can provide the specificity required for targeted biosensing applications, but also can augment the fundamental performance of microfabricated sensors.
Our team has utilized the biomaterials chitosan and calcium alginate as interfaces between electromechanical microsystems and biological elements. Electrodeposition of these materials onto electrodes enables biofunctionalization of microfabricated devices through conjugation or codeposition with proteins, DNA, cells, and other biological elements.
We have integrated chitosan with several different types of microfabricated sensor systems, including a microcantilever DNA sensor and an optical waveguide sensor integrated with microfluidic sample delivery. Chitosan and alginate together have been integrated with microfluidic systems and used to position cells in microenvironments that permit the study of interactions between different cell populations.
We have also used the Tobacco mosaic virus (TMV) to produce nanostructured microfabricated devices. Genetic engineering of the virus coat allows for spatially selective deposition of the virus on metal surfaces, and also allows for electroless metal deposition over the high aspect ratio virus structure. We have also developed the capability to use standard microfabrication techniques to pattern TMV on any type of substrate, allowing for nanostructuring a multitude of device surfaces.
In addition to nanostructuring sensors to augment sensitivity through the increased surface area, the TMV virus can also be engineered to display surface peptides that specifically bind to biological and chemical molecules. In this way, TMV can be used to create a highly selective sensor functionalization layer that can be patterned with high resolution for integration with microsensors.
This presentation will cover the technologies we have developed to integrate the above biomaterials in microfabricated sensor platforms, and will discuss the advantages conveyed through this synergy.
