Optical and optoelectronic materials derived from biopolymer, deoxyribonucleic acid (DNA)

Some of cyanine dyes and ionic functional chromophore have been widely used to probe the conformation of DNA helix through measurement of induced circular dichroism (CD) spectrum, change of UV-visible spectrum and enhancement of fluorescence. In order to develop new type optical and optoelectric materials we studied the interaction between a hemicyamnine dye and DNA in aqueous solution and have prepared the NLO dye-DNA complex films. We first found that binding of the famous NLO dyes, C22HEMI to DNA induced strong CD band in the absorption spectra of the dyes in DNA aqueous solution and DNA-CTMA complex film(1). The enhancement of the fluorescence quantum yield upon binding of the dye to DNA in aqueous solution is above 100-fold. Luminescence of the hemicyanine dyes-doped in DNA-CTMA film displayed enhancement fluorescence above three orders. Refractive indices and film thickness of the self-assembled thin film determined by using the prism coupling method revealed that the self-assembled DNA thin film has anisotropic structure in two-dimension and the self-assembled DNA-CTMA thin film is isotropic. The functional dye-DNA-CTMA film may be used to fabrication of optical waveguide, and optoelectronic devices based on the strong fluorescence, and tunable optical properties.