Photochromic diarylethene-containing DNA thermotropic liquid crystals toward information recording biomaterials with stable photopatterning resistant to heat and water

Biomaterials with reversible photochromism are attractive in biological studies. However, the photochromism of such biomaterials often suffers from self -erasing, bad thermostability and water -induced color change. In this study, with the considerations of molecular flexibility, water -solubility and electronic effect, two diarylethenecontaining ammonium surfactants are designed and synthesized for the fabrication of solvent -free photochromic DNA thermotropic liquid crystals through electrostatic complexation. All the color states of the reported DNA materials show great thermostability under heating and humid conditions. The study confirms that the electronic effect on the photochromophore plays a critical role on the photochromism and physical state of diarylethene-containing surfactants, which also decides the photochromism of DNA materials reversible or irreversible. Meanwhile, the anisotropic function of DNA turns out to be powerful on the ordered arrangement of surfactants. This study provides a designing strategy for fabricating non -self -erasing photochromic biomaterials which are also resistant to heat and water, opening new opportunities for stable information recording in biological studies.