A New Thiosemicarbazone-Based Fluorescence “Turn-on” Sensor for Zn2+ Recognition with a Large Stokes Shift and its Application in Live Cell Imaging

Abstract

Selective fluorescence turn on Zn(2+) sensor with long-wavelength emission and a large Stokes shift is highly desirable in Zn(2+) sensing area. We reported herein the synthesis and Zn(2+) recognition properties of a new thiosemicarbazone-based fluorescent sensor L. L displays high selectivity and sensitivity toward Zn(2+) over other metal ions in DMSO-H2O (1:1, v/v, HEPES 10 mM, pH = 7.4) solution with a long-wavelength emission at 572 nm and a large Stokes shift of 222 nm. Confocal fluorescence microscopy experiments demonstrate that L is cell-permeable and capable of monitoring intracellular Zn(2+). Graphical Abstract We report a new thiosemicarbazone-based fluorescent sensor (L) for selective recognition of Zn(2+) with a long wavelength emission and a large Stokes shift.

Bifunctional Receptor Based on Calix[4]arene with Chromone Groups as An Efficient Colorimetric Sensor for Co2+, Cu2+, CN− and F−

“…The latter presents hydrogen-bond donors, thiocarbonyl and imine groups (with various ligating sites: N, O, S atoms), improving the binding efficiency and selectivity toward different metal cations and anions. [33][34][35][36][37][38] Based on this background, in this work we introduced two chromone moieties into a calix [4]arene through a thiosemicarbazone bridge in the lower rim or upper rim. The new colorimetric sensors based on calix [4]arene (alternate and cone conformation) allow the detection of cations and anions via a naked-eye process.…”

“…We have studied different structures of ligating sites such as amide, thiourea and a thiosemicarbazone group. The latter presents hydrogen‐bond donors, thiocarbonyl and imine groups (with various ligating sites: N, O, S atoms), improving the binding efficiency and selectivity toward different metal cations and anions [33–38] . Based on this background, in this work we introduced two chromone moieties into a calix[4]arene through a thiosemicarbazone bridge in the lower rim or upper rim.…”

Ion sensing with a calix[4]arene bifunctional receptor with thiosemicarbazone moieties and naphthalene chromophore

“…The heteroatoms at these functional groups, facilitate speci c interactions with macromolecules via hydrogen bonding and polar interactions crucial for molecular recognition and detection. Structural motifs, such as thiosemicarbazone group [17], which includes hydrogen-bond donors, thiocarbonyls, and imines with various binding sites such as nitrogen, oxygen, and sulfur atoms, play a crucial role in enhancing binding e ciency and selectivity towards various metal cations and anions [18][19][20][21][22]. Naphthalene groups has been employed as chromophore in different sensors based on calixarene: highly selective turn off/on uorescent sensor for Cu(II) recognition [17], dual uorescence response of sensor towards Cu 2+ and I − [23], uorescent simultaneous complexation of anionic and cationic species [24], selective uorescent recognition toward p-nitrophenol [25], metallo-supramolecular complex (Cu 2+ ) emulates speci c recognition of S2 − ions [26], selective uorescent sensing of Pb 2+ [27], uorescent sensor for Au 3+ and I − [28] and 1,3-alternate calix [4]biscrown chemosensor for metal ions [29].…”

A single 8‐hydroxyquinoline‐appended bile acid fluorescent probe obtained by click chemistry for solvent‐dependent and distinguishable sensing of zinc(II) and cadmium(II)

“…There have been abundant small‐molecule fluorescent probes reported for individual sensing of Zn 2+ or Cd 2+ at present [18–38]. Regretfully, these existing fluorescent molecules could only recognize one of the two metal cations.…”