Visible light responsive photoacids for subcellular pH and temperature correlated fluorescence sensing

Abstract

Liao’s photoacids (PAs) is a well-known type of visible light-responsive photoswitches. Here, taking advantage of the temperature dependent thermal relaxation from the ring-closed to the ring-opened forms, PAs are proposed...

Ultrasensitive Ratiometric Fluorescent Nanothermometer with Reverse Signal Changes for Intracellular Temperature Mapping

“…8−11 Notable examples include fluorescent proteins, 12 small-molecule compounds, 13,14 ther-moresponsive polymers, 15,16 quantum dots, 17 lanthanide-iondoped nanoparticles, 18 vacancy-containing nanodiamonds, 19,20 and photoswitchable systems. 21,22 Given their relatively good biocompatibility, organic thermometers are well-suited for biological research. In principle, these fluorescent thermometers typically exhibit temperature-dependent changes in one or multiple fluorescence parameters, such as peak position, emission intensity, fluorescence lifetime, emission intensity ratio, fluorescence polarization anisotropy, and electron spin resonance or optically detected magnetic resonance.…”

“…Temperature, a crucial physiological parameter for living organisms, plays a pivotal role in regulating a multitude of biochemical processes, such as gene expression, signal transduction, and brown adipose tissue thermogenesis. − Abnormal temperature variations are often associated with a range of pathological changes, in which inflammation and tumorigenesis are characterized by an increase in temperature. − Therefore, achieving sensitive temperature sensing at the subcellular level is of great importance for understanding diverse physiological processes and disease states of living organisms. Among various types of thermometers, fluorescent ones are particularly advantageous for intracellular temperature sensing due to their noninvasiveness, real-time signal feedback, and sensitive signal changes. − Notable examples include fluorescent proteins, small-molecule compounds, , thermoresponsive polymers, , quantum dots, lanthanide-ion-doped nanoparticles, vacancy-containing nanodiamonds, , and photoswitchable systems. , Given their relatively good biocompatibility, organic thermometers are well-suited for biological research. In principle, these fluorescent thermometers typically exhibit temperature-dependent changes in one or multiple fluorescence parameters, such as peak position, emission intensity, fluorescence lifetime, emission intensity ratio, fluorescence polarization anisotropy, and electron spin resonance or optically detected magnetic resonance. , However, accurately reflecting minute changes in intracellular temperature remains a challenge.…”

Europium/1,3,5-Benzenetricarboxylic Acid Metal–Organic Framework Nanorods Decorated with CdSe Quantum Dots as Coatings for Noncontact Ratiometric Optical Temperature Sensing

“…The use of luminescent materials, such as organic dyes, inorganic phosphors, and quantum dots (QDs), to detect the temperature of target components with optical parameters like photoluminescence intensity and lifetime has been increasingly popular in recent times. − Temperature measurements can be accomplished without contact by combining optical temperature sensitivities with certain quantum dots’ photoluminescence while maintaining high sensitivities to temperature characteristics. For example, the reversible luminescence intensity changes and spectral shifts of CdSe QD clusters have illustrated the potential for developing sensors based on quantum dot nanoscale components.…”

Photoinduced hydrogen-bonded self-assembly of cation-capped complexes and novel photoswitchable supramolecular devices based on (aza)-18-crown-6-containing styryl dyes bearing a long N-ammonioalkyl substituent

“…Thus, these compounds can be assigned to the class of photoswitchable supramolecular compounds called photoswitchable ionophores. [23][24][25][26][27][28][29][30][31][32] In this study, we developed the synthesis and investigated the structure and photochemical and complexing properties of (aza)-18-crown-6 ether styryl dyes derived from 2-methylbenzothiazole (E)-1a-c and (E)-2a (Chart 1), which have a long-chain substituent with a terminal ammonium group at the N atom of the heterocyclic residue. Dyes (E)-1d, e and (E)-2b, which do not contain an ammonium group or have a relatively short ammonioalkyl N-substituent (Chart 1), were used as model compounds.…”

“…Thus, these compounds can be assigned to the class of photoswitchable supramolecular compounds called photoswitchable ionophores. 23–32…”