Novel Mg2+-responsive fluorescent chemosensor based on benzo-15-crown-5 possessing 1-naphthaleneacetamide moiety

Non-salen coumarin Schiff base chiral fluorescent probe turn on circularly polarized luminescence by Mg2+ and Zn2+

L1 can be used as highly sensitive dual detection ion probe for Mg2+ and Zn2+. Mg2+ and Zn2+ can turn on the CPL emission of L1. L1 showed reversible fluorescence “on/off” response with Zn2+ and EDTA.

A novel diarylethene-based fluorescent “turn-on” sensor for the selective detection of Mg2+

A new photochromic diarylethene derivative with a 4-methylphenol unit has been designed and synthesized. It displayed distinct photochromism and fluorescent ‘‘turn on’’ features to Mg²⁺ in acetonitrile solution. With the addition of Mg²⁺, there was an obvious increase of fluorescent emission intensity at 552 nm, accompanied by a clear change of fluorescent color from dark purple to green. Meantime, the 1 : 1 stoichiometry between the derivative and Mg²⁺ was verified by Job's plot and HRMS. Furthermore, the sensor was successfully applied in the detection of Mg²⁺ in practical samples. Moreover, based on the multiple-responsive fluorescence switching behaviors, it also could be used to construct a molecular logic circuit with UV/vis lights and Mg²⁺/EDTA as input signals and the emission at 552 nm as the output signal.

A new photochromic diarylethene derivative with a 4-methylphenol unit has been designed and synthesized.

Alkali and alkaline earth metal ion binding by a foldamer capsule: selective recognition of magnesium hydrate

Alkali and alkaline earth metal ion binding by an aromatic oligoamide foldamer was shown to induce its folding into a helical capsule. CD and NMR titrations revealed tight and selective binding of Mg²⁺. Crystallographic studies demonstrated that, depending on the metal, binding may involve the first or second coordination spheres of the metal hydrates.

Fluorescent probes for the detection of magnesium ions (Mg2+): from design to application

Magnesium ions (Mg²⁺) play essential roles in various physiological and pathological processes, its abnormal homeostasis in cells is related to many diseases, such as diabetes, neuromuscular disorders, hypertension and other cardiovascular disorders. Investigation on the regulation of magnesium in cellular processes has attracted considerable interest in the past several decades. Among those reported strategies, fluorescent imaging technology has become a powerful and cost-effective tool for the real-time monitoring of magnesium distribution, uptake and trafficking, due to its superior features of high sensitivity and non-invasiveness, as well as excellent spatial and temporal fidelity. Herein, we critically summarize the progresses in the intracellular magnesium detection with fluorescent imaging probes. Our discussion focuses on the recent contributions concerning fluorescent imaging probes for mapping magnesium in biological processes. All the candidates are organized according to their acceptor structures. The sensing mechanisms of fluorescent probes are also highly taken into account. Challenges, trends and prospects of fluorescent imaging technology in magnesium detection are also set forth.

Herein, progress in intracellular magnesium detection with fluorescent probes is critically summarized in this work.

Inconvertible p-tert-butylthiacalix[4]arene-core-star polystyrene conformers

Inconvertible star polystyrene conformers were synthesized by ATRP using initiators of different conformations from p-tert-butylthiacalix[4]arene. The influence of spatial structures of the star polystyrene conformers on properties was investigated.

Solvent-dependent "turn-on" fluorescence chemosensor for Mg(2+) based on combination of C=N isomerization and inhibition of ESIPT mechanisms

A fluorescent chemosensor (L) for Mg(2+) has been synthesized and characterized, which exhibits turn-on fluorescence response for Mg(2+) only in alcohol solvent (methanol or ethanol) with high sensitivity and selectivity. But in both nonpolar and polar solvents (cyclohexane, DCM, DMSO or MeCN), L showed negligible fluorescent response for Mg(2+). In order to discover the unique phenomenon, optical measurements, liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and a high performance liquid chromatography with a fluorescence detector (HPLC-FLD) of L and L with Mg(2+) ions in solvents were studied. In alcohol solvent, [L+alcohol molecule] was formed and the mechanism aspect of L concerning the remarkable fluorescence response for Mg(2+) has been discussed.

A proton-triggered ON-OFF-ON fluorescent chemosensor for Mg(II) via twisted intramolecular charge transfer

A novel fluorescent chemosensor has been synthesized and shows interesting fluorescent ON-OFF-ON processes through mediating its twisted intramolecular charge transfer (TICT) state. An exclusively fluorescent enhancement is observed for Mg (2+).