An ESIPT based versatile fluorescent probe for bioimaging live-cells and E. coli under strongly acidic conditions

Abstract

Probe BTNN undergoes a drastic upsurge (~146-fold, Φ = 69%) in fluorescence intensity (bright green, λem 530 nm) while moving from pH 7 to pH 2. MG-63 cells and E....

Highly selective chromogenic and fluorogenic probe based on benzothiazole‐thiosemicarbazone Schiff base for detection of copper (II) in real samples

“…Due to the simple synthesis, high fluorescence quantum yields, and long emission wavelength of HBT derivatives, their structure can be modified to change their fluorescence properties and alter their recognition function, become a fluorescent probe with the dual characteristics of "AIE + ESIPT" and flexible structure [36][37][38][39][40][41]. It has been reported that the protonation of the diethylamine group and its strong hydrogen bonding with the oxygen of Aldehyde group promote normal and ESIPT emission, which is responsible for the significant increase in fluorescence intensity [42].…”

First 1-hydroxy-1H-imidazole-based ESIPT emitter with an O–H⋯O intramolecular hydrogen bond: ESIPT-triggered TICT and speciation in solution

“…The ESIPT photoreaction in ESIPT-capable molecules depends strongly on the nature of media, [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50] on substituents introduced in the core of an ESIPT-capable molecule and on the degree of p-conjugation between different moieties of the molecule. [51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69] These factors affect the electronic structure of the molecule and can induce barriers between the normal and tautomeric forms on the potential energy surfaces (PESs) in the excited state, causing partial or even full frustration of the proton transfer.…”

Experimental and Theoretical Study for Proton Transfer of Aggregated‐Induced Emission Active Fluorescent Schiff Bases

“…There have been notable reports of AIE or/and ESIPT-based designs as sensing and imaging options. [23][24][25][26][27] Therefore, intending to expand knowledge in the field of molecular probe design, we investigated the effect of increasing conjugation on a tetraphenylethylene-based design, which will undoubtedly fill a research gap. As a result, we used experimental and theoretical tools to investigate and comprehend the mechanistic view of photophysical processes (aggregation-induced emission and excited state intramolecular proton transfer) on increasing conjugation by substituting the naphthalene unit (compound 3) for the phenyl unit (compound 2 3) in the presence and absence of analytes (Figure 1).…”

“…The literature describes many molecular designs based on the salicylaldehyde and naphthaldehyde with proton transfer and aggregation‐induced emission features, for example, 2‐hydroxynapthaldehyde, [8] 2‐hydroxy‐1‐naphthaldehyde semicarbazone, [9] 2,2‐dihydroxy‐1,1‐naphthalazine, [10] naphthalene based ESIPT sensor for recognition of Hg 2+ and cysteine, [11] naphthaldehyde based ESIPT sensor for F − and CN − ions, [21] triphenylamine‐salicylaldehyde based unsymmetrical azine., [22] etc. There have been notable reports of AIE or/and ESIPT‐based designs as sensing and imaging options [23–27] . Therefore, intending to expand knowledge in the field of molecular probe design, we investigated the effect of increasing conjugation on a tetraphenylethylene‐based design, which will undoubtedly fill a research gap.…”