Effects of DNA on the Formation of J-Aggregates of Pseudo-Isocyanine

We prepared the solution and film samples including pseudo-isocyanine (PIC), DNA and polyvinylalcohol (PVA) and conducted the absorption and circular dichrosim spectroscopies. The effects of DNA on the formation of J-aggregates were investigated by the dependence of optical spectra on the concentration of the dye and DNA. From the results, we found that small amount of DNA promotes the formation of J-aggregates in solution, and the maximum J-aggregate peak was obtained with the PIC iodide concentration of 1.31 x 10(-3) mol/l, which is less concentrated than usual conditions. We also succeeded to fabricate PVA films including 1.2% dye and 0.5% DNA by a spin coating method from the solution, demonstrating the J-aggregate peak and a circular dichroism signal.