A New Methoxy Poly(ethylene glycol)-anchored Anthracene for Fluorescence Sensing of Hg^2＋and Subsequent of Cysteine in Pure Aqueous Solution

Abstract

A new Methoxy poly(ethylene glycol)-anchored polymer sensor P1, which contains anthracene fluorephore and di-2-picolylamine metal ions binding site, has been easily synthesized by "click reaction". In pure aqueous solution, P1 can coordinate with Hg 2＋ quickly to form 1∶1 stoichiometry P1-Hg 2＋ complex, with quenching the fluorescence of P1. In addition, P1-Hg 2＋ shows exclusive fluorescence turn-on sensing of cysteine (Cys) over other amino acids for the displacement method.

Red to near infrared ultralong lasting luminescence from Mn2+-doped sodium gallium aluminum germanate glasses and (Al,Ga)-albite glass-ceramics

“…Upon excitation at 250 nm, all doped glasses show a pronounced, broad emission band spanning the spectral range of 550 nm to 800 nm, originating from the spin-forbidden 4 T 1 ( 4 G) -6 A 1 ( 6 S) transition in VI Mn 2+ . [30][31][32][41][42][43][44] With the increasing manganese content, the emission peak red-shifts gradually ( Fig. 3a).…”

“…At the same time, a weaker green emission band appears at B530 nm, indicating re-precipitation of Mn 2+ in a less-strong ligand field, i.e., tetrahedral IV Mn 2+ . [32][33][34] The appearance of this band is the reason for the apparent change in the PL color. The inset of Fig.…”

“…28 Mn 2+ doped glasses were also reported with red emissions with lifetime in the millisecond regime such as zinc borosilicates and germanates. [29][30][31][32][33][34] As the glass samples were devitrified, it has been found that Mn 2+ emission will turn into green emission [32][33][34][35] This is because usually tetrahedral cation sites are predominant in the crystals precipitated inside glass, and Mn 2+ ions will be driven into the tetrahedral lattice sites in the weak crystal field during the crystallization process. So far, the afterglow of VI Mn 2+ -related red photoemission is seldom longer than one hour either in crystals, glasses or glass ceramics.…”