Effect of light irradiation in the chiral complex of poly(l-lysine) with Methyl Orange

Abstract

The effect of light irradiation in the chiral complex of poly(l-lysine) (PLL) with Methyl Orange (MO) was investigated by means of absorption and circular dichroism (c.d.) measurements. Upon irradiation with ultraviolet or visible light, the magnitudes of the induced c.d. of the PLL-MO complex decreased together with a decrease in skew dimeric dye species. As more photons were irradiated, the induced c.d. decreased much faster. The lowermolecular-weight complex and higher temperature caused faster decrease of the induced c.d. The change was irreversible under dark or re-irradiation conditions.