Novel Biosensor Based on Parylene Cantilevers

Case ID:

A Wayne State University researcher has developed a novel biosensor for DNA and protein microarray applications as well as lab-on-a-chip assays. The biosensor is composed of a micro-scale cantilever made of a polymer material with a modulus of elasticity significantly less than cantilever-based biosensors utilizing silicon nitride.

Biosensors based on microfabricated cantilevers have attracted many interests in recent years. These sensors utilize the fact that when biochemical molecules (DNA antibody etc.) selectively bind to one side of the cantilever the surface stress induced will cause a mechanical bending of the cantilever. This bending is small and is usually detected by optical lever method.

The cantilever biosensor developed at Wayne State utilizes parylene C which has a Young’s modulus of 2.8 GPa two orders of magnitude smaller than that of silicon nitride. Thus the deflection of the cantilever will be more significant yielding much higher sensitivity. In addition the biosensor utilizes a piezoresistive element as the sensing mechanism.

04-712 BiosensorCantilevers


Competitive Advantages

• Cantilever biosensor exhibits high sensitivity and resolution
• Biological assays can be performed without the need of fluorescent tags and associated optical instrumentation thereby reducing the overall cost of the assay

Patent Status

Issued Patent US 8,122,761


R. B. Katragadda, Z. Wang, W. Khalid, Y. Li and Y. Xu.” Parylene cantilevers integrated with polysilicon piezoresistors for surface stress sensing”, Applied Physics Letters, 91, 083505, 2007.

R. B. Katragadda and Y. Xu, “Piezoresistive parylene cantilevers for biosensing applications”, Proceeding of the International Workshop on Nanomechanical Sensors”, Copenhagen, Denmark, May 7-10, 2006



Patent Information:
For Information, Contact:
Nicole Grynaviski
Commercialization Principal
Wayne State University
Yong Xu