Abstract
We describe a recently developed oblique-incidence reflectivity difference (OI-RD) microscope, a form of polarization-modulated imaging ellipsometer, for label-free-high-throughput detection of biomolecular reactions on DNA and protein microarrays. We present examples of application of this technique to end-point and real-time investigations of DNA-DNA hybridization, antibody-antigen capture, and protein-small-molecule binding reactions. Compared to a conventional imaging ellipsometer based on the polarizer-compensator- sample-analyzer scheme and under the off-null condition, a polarization- modulated OI-RD microscope is inherently more sensitive by at least 1 order of magnitude to thickness changes on a solid surface. Compared with imaging surface plasmon resonance microscopes based on reflectance change on falling or rising slopes of the surface plasmon resonance, the OI-RD microscope (1) has a comparable sensitivity, (2) is applicable to conventional microscope glass slides, and (3) easily covers a field of view as large as the entire surface of a 1 in. × 3 in. (2.54 cm × 7.62 cm) microscope slide.
Original language | English (US) |
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Pages (from-to) | 1890-1895 |
Number of pages | 6 |
Journal | Applied Optics |
Volume | 46 |
Issue number | 10 |
DOIs | |
State | Published - Apr 1 2007 |
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics