Recent Advances in Cyclodextrin‐Based Light‐Responsive Supramolecular Systems

Abstract

Cyclodextrins (CDs), one of the host molecules in supramolecular chemistry, can host guest molecules to form inclusion complexes via non-covalent and reversible host-guest interactions. CD-based light-responsive supramolecular systems are typically constructed using CDs and guest molecules with light-responsive moieties, including azobenzene, arylazopyrazole, o-nitrobenzyl ester, pyrenylmethyl ester, coumarin, and anthracene. To date, numerous efforts have been reported on the topic of CD-based light-responsive supramolecular systems, but these have not yet been highlighted in a separated review. This review summarizes the efforts reported over the past ten years. The main text of this review is divided into five sections (vesicles, micelles, gels, capturers, and nanovalves) according to the formation of self-assemblies. This feature article aims to afford a comprehensive understanding of the light-responsive moieties used in the construction of CD-based light-responsive supramolecular systems and to provide a helpful guide for the further design of CD-based light-responsive supramolecular systems.

Design and Applications of Photoresponsive Hydrogels

“…[58] Thiol-ene "click" chemistry found widespread application in polymer chemistry and also made its way into the design of photoresponsive hydrogels. [66] Spiropyran isomerizes from the hydrophobic closering form to the hydrophilic open ring merocyanine zwitterion under the irradiation of 365 nm. [62,63] Notably, thiol or disulfide reactions proceeding via a radical mechanism are fundamen tally different from electrocyclic cycloadditions, which proceed via a concerted cyclic transition state.…”

Designing Molecular Photoswitches for Soft Materials Applications

“…In this context, the complexation of cyclodextrin (CD) hosts by azobenzene guests has been proven very valuable since the binding constants of E and Z isomers to the CD's hydrophobic cavity differ severely . Many supra‐ and macromolecular systems based on this azobenzene–CD interaction have been developed, in particular by Harada and co‐workers …”

pH‐responsive chitosan/sulfobutyl ether‐β‐cyclodextrin supramolecular nanoparticles for controlled release of sodium ferulate

“…In the past few decades, controllable supramolecular nanoassembly constructed by several kinds of weak noncovalent interactions [1,2] have attracted considerable research interest because of their ease of preparation and good practical application in functional materials and biochemistry. [3][4][5] Supramolecular assembly is an effective approach for the construction of nanoparticles that can effectively control the release of drugs at specific sites through external multi-stimulus, such as pH, [6,7] temperature, [8] light, [9,10] redox, [11,12] enzyme, [13] electricity. [2] Among the various stimuli, variation in pH is the most frequently used, as pH values in different tissues and cellular compartments vary tremendously.…”