Photo‐Modulated Reversible Switching of Fluorescence from ZnO Quantum Dots with a Photochromic Diarylethene

Construction of a Reversible Solid-state Fluorescence Switching Via Photochromic Diarylethene and Si-ZnO Quantum Dots

Developing fluorescence switching as functional system is highly desirable for potential applications in the fields of light-responsive materials or devices. Attempt to construct fluorescence switching system tend to focus on the high fluorescence modulation efficiency, especially in solid state. Herein, a photo-controlled fluorescence switching system was constructed with photochromic diarylethene and trimethoxysilane modified zinc oxide quantum dots (Si-ZnO QDs) successfully. It was verified by the measurement of modulation efficiency, fatigue resistance as well as theoretical calculation. Upon irradiation with UV/Vis lights, the system exhibited excellent photochromic property and photo-controlled fluorescence switching performance. Furthermore, the excellent fluorescence switching characters could also be realized in solid state and the fluorescence modulation efficiency was determined to be 87.4%. The results will provide new strategies to the construction of reversible solid-state photo-controlled fluorescence switching for the application in the fields of optical data storage and security labels.

A photo-controlled fluorescent switching based on carbon dots and photochromic diarylethene for bioimaging

Carbon dots (CDs) as luminescent zero-dimensional carbon nanomaterials have good aqueous dissolution, photostability, high quantum yield, and tunability of emission color. It has great application potential in many fields, including bioimaging, labeling of biological species, drug delivery, and sensing in biomedical. However, controlling the fluorescence emission of carbon dots remains a formidable challenge. Herein, we designed and exploited a photo-controlled fluorescent switching based on photochromic diarylethene (DT) and CDs for bioimaging. It could be modulated reversibly between "ON" and "OFF" under UV/vis light exposure. The fluorescent modulation efficiency was as high as 95.3%. The fluorescent switching could be used to the bioimaging in HeLa cells with low cell toxicity. Therefore, this fluorescent switching could be a promising candidate in many potential application areas, especially in bioimaging.

Construction of a photo-controlled fluorescent switching with diarylethene modified carbon dots

Photo-controlled fluorescent switching is of great utility in fluorescence sensors, reversible data storage, and logic circuit, based on their modifiable emission intensity and spectra. In this work, a novel photo-controlled reversible fluorescent switching system was constructed based on photochromic diarylethene (DT) molecular modified fluorescent carbon dots (CDs). The fluorescent CDs acted as fluorescent donors and the photochromic diarylethene molecular functioned as acceptors in this fluorescent switching system. The fluorescence modulation efficiency of the fluorescent switching was determined to be 97.1%. The result was attributable to Förster resonance energy transfer between the CDs and the diarylethene molecular. The fluorescent switching could undergo 20 cycles without significant decay.