The effects of phenyl-bridged glucosyltriazolyl groups on the properties of water-soluble diarylethene derivatives

A novel full symmetric diarylethene-based ratiometric fluorescent sensor for lysine and the application for a logic circuit

A novel diarylethene-based ratiometric fluorescent sensor with full symmetric structure, 1o, was designed and synthesized successfully. 1o could identify lysine (Lys) with high selectivity and sensitivity and the fluorescence emission peak was red shifted 85 nm upon addition of Lys, which could realize ratio recognition. It exhibited excellent anti-interference performance in the presence of various amino acids in CH₃ CN/H₂ O (7/3, v/v) solution. Moreover, the limit of detection of 1o to Lys could reach 0.019 μM based on a good linear range of 0-40 μM. In addition, the fluorescence emission intensity of 1o could be turned off/on by ultraviolet/visible light due to the special structure of diarylethene. A logic circuit was designed with three inputs. The ratiometric fluorescent sensor 1o could be as a new tool and provide a new method for detection of Lys.

Design, synthesis and investigation of water-soluble hemi-indigo photoswitches for bioapplications

A series of hemi-indigo derivatives was synthesized and their photoswitching properties in aqueous medium were studied. The dimethoxy hemi-indigo derivative with the best photochromic performance in water was identified as a promising platform for the development of photoswitchable binders for biomolecules. The synthetic approach towards the introduction of the alkylamino pendant to the dimethoxy hemi-indigo core was developed that allowed to obtain an RNA-binding hemi-indigo derivative with photoswitchable fluorescent properties.

Connectivity pattern modifies excited state relaxation dynamics of fluorophore-photoswitch molecular dyads

In order to modulate the emission of BODIPY fluorophores, they were connected to a diarylethene (DAE) photoswitch via phenylene-ethynylene linkers of different lengths and orientations. The latter allowed for modulation of the electronic coupling in the prepared four BODIPY-DAE dyads, which were compared also to appropriate BODIPY and DAE model compounds by steady state as well as time-resolved spectroscopies. In their open isomers, all dyads show comparable luminescence behavior indicative of an unperturbed BODIPY fluorophore. In strong contrast, in the closed isomers the BODIPY emission is efficiently quenched but the deactivation mechanism depends on the nature of the linker. The most promising dyad was rendered water-soluble by means of micellar encapsulation and aqueous suspensions were investigated by fluorescence spectroscopy and microscopy. Our results (i) illustrate that the electronic communication between the BODIPY and DAE units can indeed be fine-tuned by the nature of the linker to achieve fluorescence modulation while maintaining photoswitchability and (ii) highlight potential applications to image and control biological processes with high spatio-temporal resolution.