A Systematic Study on the Relationship Between Viscosity Sensitivity and Temperature Dependency of BODIPY Rotors

Abstract

Different functions of molecular rotors based on viscosity sensitivity and temperature dependence.

Cytotoxic BODIPY-Appended Half-Sandwich Iridium(III) Complex Forms Protein Adducts and Induces ER Stress

“… This feature is characteristic of BODIPY-based molecular rotors with an aryl substituent at the meso position for which both fluorescence intensity and lifetime depend on viscosity. However, the presence of methyl substituents at positions 1, 3, 5, and 7 of the BODIPY core made the viscosity response modest (x = 0.18) in agreement with the literature …”

“…However, the presence of methyl substituents at positions 1, 3, 5, and 7 of the BODIPY core made the viscosity response modest (x = 0.18) in agreement with the literature. 27 As the stock solution of IrBDP is prepared in DMSO, all the following experiments are carried out using the exchanged form IrBDP + except for reactivity studies. Prior to cell assays, the octanol−water partition coefficient (log P) of IrBDP + was determined to be 0.95 by the classical "shake flask" method using absorption readout.…”

A palette of site-specific organelle fluorescent thermometers

“…According to our previous study, the viscosity sensitivity of BODIPY rotors was reversely correlated to the transformation energy barrier from the planar structure to the butterfly-like form [ 25 ]. By modifying BODIPY cores, the unsymmetrical BODIPY (named ETG in this work) possessed the lowest energy barrier, and has been reported to be the most viscosity-sensitive BODIPY so far [ 26 ]. In other words, ETG can be a promising scaffold to sense the change in the physical microenvironment as the detectable fluorescence signal with high sensitivity.…”

“…In other words, ETG can be a promising scaffold to sense the change in the physical microenvironment as the detectable fluorescence signal with high sensitivity. Therefore, it is expected that ETG (ER Thermo Green) may also exhibit good sensitivity to the intracellular temperature change [ [25] , [26] , [27] ]. Starting from the structure of ETG, an expanded series of green fluorescent thermometers covering almost all typical organelles were synthesized ( Scheme 1 ).…”

“…In similar with the other types of previous fluorescent thermometers, the slopes were also fitted well with linear curves within a narrow range of physiological temperature [ 11 ]. Here, it should also be noted that a BODIPY rotor molecule is known to be sensitive to both viscosity and temperature [ 26 , 35 ]. When the fluorescence signal is altered in response to the temperature increment, it is quite challenging to separate the temperature effect from the viscosity effect because the temperature increment is also accompanied by the viscosity change at the same time.…”