Design of red-shifted and environment-sensitive fluorogens based on GFP chromophore core

Meta-CF3-Substituted Analogues of the GFP Chromophore with Remarkable Solvatochromism

“…Both substances 2b and 2f were obtained as a mixture of E and Z isomers at the styrene part, which indicates a lower isomerization barrier and, hence, easier release of excitation energy. The most substantial red-shift was observed for derivative 3 , which correlates well with previously published data [ 18 , 19 , 25 ]. At the same time, compounds 2 were characterized by a very large Stokes-shift (more than 100 nm), due to which their emission spectra were close to those of derivative 3 , while the absorption spectra lay in the shorter wavelength region ( Figure 2 ).…”

“…Another modification that can lead to the red-shift of absorption and emission maxima is the expansion of the conjugated pi-system. As we have previously shown [ 18 , 22 , 25 ], this modification allows the solvent-dependent FQY variation to remain for other chromophores. We obtained similar results for compounds 1a and 1f —all expanded analogues 2 and 3 also demonstrate high FQY in aprotic and non-polar media and relatively low FQY in water ( Table 2 , Figure 2 ).…”

“…Previously, this behavior had only been observed in a limited range of compounds that either contained electron-acceptor groups in the para-position (e.g., nitro, nitrile, or carboxyl groups [ 25 ], as well as 4-pyridile derivatives [ 18 , 19 ]), or simultaneously possessed two electron-donating substituents in the opposite ortho- and meta-positions ( Scheme 1 ) [ 25 , 26 ]. These compounds were used as “polarity sensors” in fluorescent microscopy for labelling of the endoplasmic reticulum (ER) [ 18 , 22 , 25 ], mitochondria [ 19 ], and lipid droplets of live cells [ 27 ]. The presence of such pi-electron-withdrawing or pi-electron-donating groups should obviously change the nature of the frontier orbitals, thereby affecting fluorescence intensity.…”

A multi-modal probe for trace water and simultaneously monitoring lipid droplets and lysosomes

“…[34][35][36][37] Fluorescence staining is an indispensable method to study biological and environmental systems. 38,39 To date, based on different response mechanisms, a large number of fluorescent probes have been designed for biological imaging and environmental monitoring, such as intramolecular charge transfer (ICT), 40 twisted intramolecular charge transfer (TICT), 41 aggregation-induced luminescence (ATE), 42,43 photoinduced electron transfer (PET), 44 etc. However, most of the probes used in the published reports for the simultaneous imaging of lipid droplets and lysosomes are based on ICT and TICT mechanisms.…”

Synthesis and Fluorescence Mechanism of the Aminoimidazolone Analogues of the Green Fluorescent Protein: Towards Advanced Dyes with Enhanced Stokes Shift, Quantum Yield and Two‐Photon Absorption

“…The unique properties of the GFP fluorophore enabled the development of dyes with aggregation induced emission [22] or temperature induced fluorescent enhancement, [23] and viscosity sensor molecules [24] . GFP‐like chromophores have also been applied in bioimaging as fluorescent stains or tags [19,25–27] . However, certain applications have been hindered by the low QY of the basic chromophore [26] .…”