Solvent-dependent photophysics of a red-shifted, biocompatible coumarin photocage

Abstract

A novel coumarin photocage with long-wavelength and high photolysis quantum yield shows solvent dependent photolysis.

Exploring the Relationship between BODIPY Structure and Spectroscopic Properties to Design Fluorophores for Bioimaging

“…When compared to their reference compounds 5 and 8,t he solvatochromic shift between the two solvents is also almostt wice as large with the mono-substituted compound 16 than with the double- substituted compound 15.T his is due to the introductiono f the diethylamino group only present in compound 16. [28,29] Finally,b and gaps for all compoundsw ere computationally calculated by using time-dependant density functional theory (TD-DFT) calculations. For the calculations of compounds 11 and 12,i odine was substituted by bromine as iodine is not compatible with this calculation base.…”

“…[5] Furthermore, to induce strong solvatochromism,w hichi se ssential for environmental sensing,t wo diethyl-amino groups were installed ( Figure 3). [28,29] Amino groupsc an render fluorophores highly sensitivet os olventp olarity [30] and also contribute to longer absorption wavelengths. [29] Thec ompact amphiphilic design of HiBO is aimed to counter commoni ssues of other long wavelength,y et lipophilic non-BODIPY probes, such as poor biological compatibility,c ompromised fluorescencee missiona nd limited retention within membranes.…”

“…[28,29] Amino groupsc an render fluorophores highly sensitivet os olventp olarity [30] and also contribute to longer absorption wavelengths. [29] Thec ompact amphiphilic design of HiBO is aimed to counter commoni ssues of other long wavelength,y et lipophilic non-BODIPY probes, such as poor biological compatibility,c ompromised fluorescencee missiona nd limited retention within membranes. [31] Finally,t he selection of bromine on the meso-position should allow for bioconjugation of the dyei nf ollow-up studies.…”

“…When compared to their reference compounds 5 and 8 , the solvatochromic shift between the two solvents is also almost twice as large with the mono‐substituted compound 16 than with the double–substituted compound 15 . This is due to the introduction of the diethylamino group only present in compound 16 …”

“…The substituents were placed at the 3‐ and 5‐positions, which are known from the previous results (compounds 15 and 16 ) to accommodate substitutions that result in a more red‐shifted absorption wavelength (Figure ) . Furthermore, to induce strong solvatochromism, which is essential for environmental sensing, two diethyl‐amino groups were installed (Figure ) . Amino groups can render fluorophores highly sensitive to solvent polarity and also contribute to longer absorption wavelengths .…”