A photo-responsive macroscopic switch constructed using a chiral azo-calix[4]arene functionalized silicon surface

Abstract

A photo-responsive macroscopic switch was fabricated using a chiral azo-calix[4]arene derivative (FC4AD) functionalized silicon surface and exhibited selective and reversible recognition of (1R,2S)-1-amino-2-indanol through the variation of wettability. This photo-responsive device may have wide applications in controlled release of chiral drugs and in biosensors.

A Chirality/Light Dual‐Responsive Calixarene‐Functionalized Gold Surface for the Separation of Naproxen Enantiomers

“…This showed the value of 136.3±2.0°, which confirmed the isomerization of trans CAC4 on the surface into cis CAC4. Furthermore, exposure of cis CAC4‐modified surface to visible light (450 nm), for the period of 30 min, caused cis‐trans isomerization of CAC4‐modified surface, which was evidenced by the contact angle measurement of 125.1±2.0° . Reversible trans‐cis isomerization of CAC4‐modified gold surface was confirmed by the cyclic trans‐cis isomerization for the period of 5 cycles, where the contact angle of the surface switches between 125.1±2.0° ( trans ) and 136.3±2.0° ( cis ) respectively (Figure c).…”

“…In addition, chiral recognition and separation of drug enantiomers under the influence of stimuli, such as heat, light and ultra sound, will make them more specific . Among the various stimuli, light is non‐invasive, harmless to environment and living beings, application over the target can be controlled by parameters such as intensity, wavelength and time . Certain chromophores, such as spiropyran, azobenzene and diarylethene are well known molecular switches, which can be well utilized to develop photo‐responsive chiral supramolecular systems …”

Macroscopic Chiral Recognition by Calix[4]arene‐Based Host–Guest Interactions

“… ( S )‐Mandelic acid was introduced as a chiral auxiliary to enable the resulting calixarene derivative to differentiate between the chiral enantiomers of naproxen through host–guest interactions Two chiral units were simultaneously incorporated onto the upper rim of calixarene to impart superior recognition ability between the different enantiomers through a synergistic effect …”

“…( S )‐Mandelic acid was introduced as a chiral auxiliary to enable the resulting calixarene derivative to differentiate between the chiral enantiomers of naproxen through host–guest interactions …”

Hydrogels Self‐Assembled from an Azobenzene Building Block: Stability toward UV Irradiation in the Gel and Thin‐Film States

“…The change of configuration after UV light irradiation always result in the change of systems' properties, such as gelsol transitions, [14] binding and releasing guest molecules, [15] association-dissociation of aggregates, [16] deformation of colloidal particles [17] and changing of morphology. The change of configuration after UV light irradiation always result in the change of systems' properties, such as gelsol transitions, [14] binding and releasing guest molecules, [15] association-dissociation of aggregates, [16] deformation of colloidal particles [17] and changing of morphology.…”