Photochromic fluorophores at the molecular and nanoparticle levels: fundamentals and applications of diarylethenes

Abstract

Fluorescent molecules and materials are widely used in many areas in physics, chemistry, and biology as emitters, tags, or sensors. The possibility of controlling their fluorescence signal by light, namely, fluorescence photoswitching, down to the nanoscale level can then dramatically extend their fields of applications. This review focuses on fluorescent and photochromic diarylethene-based nanosystems. The choice of the diarylethene family has been driven by its excellent photoswitching properties (conversion yield, bistability, fatigue resistance), which make them fully appropriate when high-performance behavior is required. The different molecular and nanomaterial designs providing suitable combinations of fluorescence and photochromism are summarized. Besides the inherently fluorescent diarylethene molecules, chemical association between photochromic and fluorescent molecular units can advantageously lead to fluorescence photoswitching thanks to resonance energy transfer or intramolecular electron transfer processes. Furthermore, the preparation of nanoscale emissive materials involving diarylethene units paves the way to new interesting features, such as near-infrared control of emissive and photoswitchable nanohybrids, giant amplification of the fluorescence photoswitching in organic nanoparticles, or fluorescence color modulation. Many applications derived from such fluorescent diarylethene-based molecules and nanomaterials have been developed recently, especially in the field of biology for fluorescence biolabeling and super-resolution imaging but also for photocontrol of biological functions. Extremely promising prospects are expected in the near future.

A simplicity-guided cocktail approach toward multicolor fluorescent systems

“…Notes and references ‡ There are examples of other DAE derivatives with similar or higher fluorescence quantum yields in the open isomeric form. 32,[38][39][40][41][42][43][44] In these compounds, however, the emission is originating from a distinct fluorophore associated with the photoswitch, and not integral part of the same.…”

Reversible Upconversion Luminescence Modification Based on Photochromism in BaMgSiO4:Yb3+,Tb3+ Ceramics for Anti‐Counterfeiting Applications

“…Reversible modification of photoluminescence has been shown to have an extensive range of applications in optical storage, rewritable paper, and optical switches . To date, research on photochromic materials has been focused on organic molecules such as diarylethenes, bisthiazolylcoumarin, spiropyrans, and azobenzenes . However, the shortcomings of organic molecules, such as their poor thermal stability, high synthetic costs, and environmental toxicity, restrict their application.…”

“…[4][5][6] To date, research on photochromic materials has been focused on organic molecules such as diarylethenes, bisthiazolylcoumarin, spiropyrans, and azobenzenes. [7][8][9][10][11][12][13][14] However, the shortcomings of organic molecules, such as their poor thermal stability, high synthetic costs, and environmental toxicity, restrict their application. In contrast to organic photochromic materials, inorganic photochromic materials have many advantages, including high thermal stability, long-term stability, and strong oxidation resistance.…”

Di(benzothienyl)cyclobutenes: Toward Strained Photoswitchable Fluorophores

“…The most useful are DAEs with benzo[b]thiophene dioxide (sulfone) substituents ( Figure 1) in which ethene double bond is a part of polyfluorinated cyclopentene ring. [3] They can interconvert between dark open form and fluorescent closed form under UV or visible light illumination. , [4,5] These DAEs are thermally stable, display high fatigue resistance and, which is the most important aspect for imaging, exhibit a large difference between the fluorescence intensity in the open and the closed forms.…”