AbstractPhotochromic supramolecular hydrogels are versatile materials that show macroscopic effects upon irradiation, like liquefaction or shape changes. Here, we demonstrate a simple photochromic cyclic dipeptide (2,5‐diketopiperazine‐based) supergelator, composed of (S)‐lysine and an azobenzene analogue of phenylalanine, that forms supramolecular hydrogels even at 0.1 wt% loading. The gels can physically encapsulate cargo molecules and release them to the environment in a controllable manner upon irradiation with red light, thus working as a “molecular syringe”. As the material is biocompatible and operational in the “therapeutic window” of light (>650 nm) that deeply penetrates soft human tissues, it is applicable to smart drug‐delivery systems.
摘要光致变色超分子水凝胶是一种多功能材料,在辐照下会产生宏观效应,如液化或形状变化。在这里,我们展示了一种简单的光致变色环状二肽(2,5-二酮哌嗪基)超凝胶体,它由 (S)- 赖氨酸和苯丙氨酸的偶氮苯类似物组成,即使在负载量为 0.1 wt% 的情况下也能形成超分子水凝胶。这种凝胶可以物理封装货物分子,并在红光照射下以可控方式将其释放到环境中,从而起到 "分子注射器 "的作用。由于这种材料具有生物相容性,并可在光的 "治疗窗口"(650 纳米)内工作,能深入穿透人体软组织,因此适用于智能药物输送系统。