(316e) Detection of Double and Single-Stranded DNA by 5CB | AIChE

(316e) Detection of Double and Single-Stranded DNA by 5CB


Malone, S. M. - Presenter, University of Colorado at Boulder
Schwartz, D. K. - Presenter, University of Colorado at Boulder

We have investigated the disruption of azimuthal alignment of the liquid crystal 5CB by double and single-stranded DNA at the solid-liquid crystal interface. A liquid crystal-based microarray has the potential to reduce expenses when compared to similar fluorescence-based systems, both with equipment capital and the elimination of the chemistry behind fluorescent labeling. Simplification of imaging equipment to a simple crossed polarized system also could increase availability of rapid genetic screening, expanding availability to diagnostic applications. Ultimately, hybridization detection could lead to a liquid-crystal based microarray. This approach uniquely differentiates between double or single-stranded DNA by detecting the inherent structure of DNA rather than detection of a molecular labeling agent. Sensitivity to the native state of DNA eliminates detection problems through nonspecific DNA binding to a sensor. We observed a minimum threshold for sensitivity has been observed to be 200 molecules per mm2 with theoretical sensitivity as low as 30 molecules per mm2. Combined polarized and fluorescence microscopy is used to simultaneously observe physical alignment of DNA as well as liquid crystal alignment. Anchoring energies of double and single-stranded DNA are also compared to further quantify disruption of the director field.