Nanostructuring porous evanescent wave biosensors

CHED 327

Pierre-Emile J. Duhamel, pduhamel@fas.harvard.edu1, Cecile S. Bonifacio, mmcneil@email.sjsu.edu2, Lilian Chang2, Melanie McNeil2, Teddie P. Magbitang, teddie@almaden.ibm.com3, Jane E. Frommer, frommer@almaden.ibm.com3, Victor Y. Lee3, Oun-Ho Park3, C. Michael Jefferson3, William P. Risk3, Ho-Cheol Kim, hckim@us.ibm.com3, Joseph Sly, joesly@us.ibm.com3, and Robert D Miller, rdmiller@almaden.ibm.com3. (1) Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, (2) Department of Chemical and Materials Engineering, San Jose State University, San Jose, CA 95192, (3) Advanced Organic Materials Department, IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120
Evanescent wave biosensors are capable of real-time, ultra-sensitive detection of biomolecules without pre-tagging the analyte of interest. Traditionally, sensing occurs through chemical recognition, where selective binding of analyte material to the sensor surface results in detectable changes to the surface plasmon resonance. This study aims to augment chemical ligation through incorporating a capacity for size-selectivity onto the sensor surface. This novel combination of both chemical and physical molecular recognition aims to enhance the sensitivity and selectivity when screening complex biological mixtures. Physical nanostructuring of plasmonic sensor surfaces was achieved using a robust microfabrication process. Composite thin films of polystyrene star-polymers and silicate precursors were first spun onto a stabilized gold-coated substrate. Subsequent vitrification, resulting in concomitant immolation of the star-polymer porogen, produced a random porous surface morphology onto the sensor surface. Analyte specific tailoring of the chemical and physical molecular recognition elements formed from this general process are in progress.