Thermodynamic stability of cis -azobenzene containing DNA materials based on van der Waals forces.

Taking advantage of van der Waals forces, an azobenzene-containing surfactant with a stable cis -state was designed and synthesized to fabricate photoresponsive DNA material. The reported DNA material exhibited reversible liquid crystalline-to-isotropic liquid transition under UV/Vis illuminations via the trans - cis isomerization of azobenzene. It also gained the ability to maintain the isotropic liquid state after UV light had ceased thanks to the thermodynamic stability of the cis -isomer of the azobenzene-containing surfactant. This work provides a design strategy for fabricating photoresponsive phase-change biomaterials.