Controllable self-assembly of an amphiphilic drug with β-cyclodextrin and α-amylase

Herein, we report a novel responsive assembly system consisting of an amphiphilic drug fenspiride and β-cyclodextrin in host–guest approach. Fenspiride molecules can self-assembled into vesicles in aqueous solution. The obtained vesicles were characterized in detail by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Furthermore, such a vesicular structure will be destroyed upon the addition of β-cyclodextrin due to the formation of inclusion complexes by host–guest interactions. In addition, amylase is a digestive enzyme which can catalyze the breakdown of starch into sugars. Adding α-amylase into the system could release fenspiride molecules, and trigger the self-assembly of fenspiride molecules again. It is anticipated that this research will provide widespread applications in the fields of responsive materials and biochemistry related to enzyme-responsive model system and host–guest chemistry.