Near-infrared fluorescent probes based on piperazine-functionalized BODIPY dyes for sensitive detection of lysosomal pH

Lee

et al. 2017

ACS Sens.

Self Cite

Two water-soluble near-infrared luminescent probes, which possess both conventional intense Stokes fluorescence and unique single-photon frequency upconversion luminescence (FUCL), were developed for sensitive and selective detection of pH changes in live cells. The water solubility and biocompatibility of these probes were achieved by introducing mannose residues through 2,2′-(ethylenedioxy)diethylamine tethered spacers to a near-infrared conventional fluorescence (CF) and FUCL organic fluorophore. At a pH higher than 7.4, the probes have ring-closed spirocyclic lactam structures, thus are colorless and nonfluorescent. Nevertheless, they sensitively respond to acidic pH values, with a drastic structural change to ring-opened spirocyclic lactam forms, which cause significant absorbance increases at 714 nm. Correspondingly, their near-infrared CF and FUCL intensities at 740 nm are also significantly enhanced when excited by 690 and 808 nm, respectively. The probes hold a variety of advantages such as high sensitivity, excellent reversibility and selectivity to pH over metal ions, low cellular autofluorescence background interference, good cell membrane permeability and photostability, as well as low cytotoxicity. Our results have successfully proven that these probes can visualize intracellular lysosomal pH changes in live cells by monitoring both near-infrared CF and FUCL changes.

mentioning

confidence: 99%

Luminescent Probes for Sensitive Detection of pH Changes in Live Cells through Two Near-Infrared Luminescence Channels

Zhang¹,

Lee

et al. 2017

ACS Sens.

Self Cite

“…Some feasible methods including electrochemical [5], nuclear magnetic resonance (NMR) [6], acid-base indicator titration [7] and spectral probe [8] have been employed to measure pH. Among them fluorescent probe have received much more attention due to its excellent sensitivity, non-destructivity, short response time, simple operation, low cost and the ability to continuous monitoring the rapid kinetic pH changes [9][10][11][12].…”

mentioning

confidence: 99%

An easily Prepared Fluorescent pH Probe Based on Dansyl

Sha

et al. 2016

J Fluoresc

A novel fluorescent pH probe from dansyl chloride and thiosemicarbazide was easily prepared and fully characterized by (1)H NMR, (13)C NMR, LC-MS, Infrared spectra and elemental analysis. The probe exhibited high selectivity and sensitivity to H(+) with a pK a value of 4.98. The fluorescence intensity at 510 nm quenched 99.5 % when the pH dropped from 10.88 to 1.98. In addition, the dansyl-based probe could respond quickly and reversibly to the pH variation and various common metal ions showed negligible interference. The recognition could be ascribed to the intramolecular charge transfer caused by the protonation of the nitrogen in the dimethylamino group.

“…6 Compared with other detection methods, the noninvasive fluorescent probes have advantages such as high selectivity and the ability for real-time detection. 9,10 The newly developed fluorescent pH chemosensors include aminophthalimide, 11 cyanine, 12 aminophthalimide, 4 benzoxanthenes, 13 BODIPY dyes, 14,15 fluorescein and it derivatives. 9,10 The newly developed fluorescent pH chemosensors include aminophthalimide, 11 cyanine, 12 aminophthalimide, 4 benzoxanthenes, 13 BODIPY dyes, 14,15 fluorescein and it derivatives.…”

mentioning

confidence: 99%

Novel Rhodamine B and 2H‐benzo[b][1,4]oxazin‐3(4H)‐one‐derived Fluorescent Sensor for Low pH Value Detection

Bulletin Korean Chem Soc

Bai

et al. 2019

A new fluorescent probe L fusing the rhodamine B scaffold with 2H-benzo[b][1,4]oxazin-3(4H)-one moiety has been developed and applied as an acidic pH sensor. The ultraviolet (UV) and fluorescence spectra of the probe at different pH values were investigated in B-R buffer/MeOH (v: v = 3: 7). This probe showed increase of both the UV-Vis absorption and fluorescence emission from alkaline/neutral to acidic condition, reaching a strongest intensity at pH 2.13, but the intensities decreased when the pH decreased to 1.83. The color variation along the pH changes proved that the probe L can be used as a low-cost optical sensor for the naked eye detection of proton in the present buffer.