Controlled Drug Release from Cyclodextrin-Gated Mesoporous Silica Nanoparticles Based on Switchable Host-Guest Interactions.

With the development of materials science and pharmaceutics, the application of mesoporous silica nanoparticles with a gated switch in the field of drug delivery has attracted much attention in the past decades. Cyclodextrins (CD) as promising gated materials have become a new area of interest in recent years due to their properties of self-assembly and function of host-guest interaction. CD is one kind of extensively studied host molecules and the host-guest interactions with different guest molecules can respond to different signals, and thus can be applied as intelligent gated switches for smart drug carriers. Switchable gatekeepers based on CD hosts with different guest molecules (such as benzimidazole, azobenzene, and ferrocene) respond to different stimuli modes (such as pH, light, and redox) that change the host-guest interactions and trigger drug release. The different structural features, mechanisms of action, and potent applications of these switchable gatekeepers are discussed. In addition, some personal perspectives and challenge on this field are presented.