IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Biomaterials Friday Sessions
       Session BI-FrM

Paper BI-FrM9
Surface Chemistry for a Membrane-based Biosensor@footnote 1@

Friday, November 2, 2001, 11:00 am, Room 102

Session: Biosensors
Presenter: C. Cole, Nova Research, Inc.
Authors: C. Cole, Nova Research, Inc.
M. Natesan, Geo-Centers, Inc.
M. Malito, Nova Research, Inc.
R.J. Colton, Naval Research Laboratory
L.J. Whitman, Naval Research Laboratory
Correspondent: Click to Email
A multianalyte biosensor has been developed that uses magnetic force to differentiate between specific and nonspecific ligand-receptor/ligand-surface interactions.@footnote 2@ The initial sensor was developed as a 36-well microtitre plate, using surface chemistries developed to modify polystyrene.@footnote 3@ In order to enhance sensitivity, reduce assay time, and increase portability, a second generation sensor is being developed that replaces the polystyrene with an alumina ultrafiltration membrane. Although the use of inorganic supports is not necessarily novel, the application of polymer coatings designed to reject protein adsorption to such a surface is. We have developed methods to introduce desired surface functionalities onto commercial membranes. At the same time, we have addressed the potentially more critical issue of ensuring that our coatings are highly reproducible, thus providing for a biosensor with consistent response. To supplement XPS, semi-quantitative methods have been developed to specifically determine the extent of poly(ethyleneimine) and poly(ethyleneglycol) coverage; resulting lots of derivatized surfaces have been found to be indistinguishable in assay use. The membrane-based biosensor has been used to detect proteins, bacteria, and viral particles in 25 minutes or less, with an enhancement in sensitivity of 2-3 orders of magnitude compared to the initial prototype (e.g., 10@super 3@ pfu/mL MS2 vs. 10@super 5@ pfu/mL on the plate-based sensor). Various arraying technologies are being evaluated, including photolithography with activated biotin, mechanical masking, and arraying through site-specific chemistry. Use of these technologies to produce an arrayed filter for multianalyte detection will be discussed. @FootnoteText@ @footnote 1@ Supported by the Joint Technical Panel for Chemical and Biological Defense @footnote 2@ Lee et al., Anal. Biochem. 287, 261 (2000) @footnote 3@ Metzger et al., J. Vac. Sci. Technol. A 17, 2623 (1999).