Synthesis of New Zinc Phthalocyanines Including Schiff base and Halogen; Photophysical, Photochemical, and Fluorescence Quenching Studies

2021 ◽  
pp. 130423
Author(s):  
Murat Yüzeroğlu ◽  
Gülnur Keser Karaoğlan ◽  
Gülşah Gümrükçü Köse ◽  
Ali Erdoğmuş
Keyword(s):  
Schiff Base ◽  
Fluorescence Quenching ◽  
Zinc Phthalocyanines

A highly selective fluorescent chemosensor based on naphthalimide and Schiff base units for Cu2+ detection in aqueous medium

2017 ◽  
Vol 72 (1) ◽  
pp. 35-41 ◽  
Author(s):  
Yuling Xu ◽  
Stephen Opeyemi Aderinto ◽  
Huilu Wu ◽  
Hongping Peng ◽  
Han Zhang ◽  
...  
Keyword(s):  
Schiff Base ◽  
Fluorescence Quenching ◽  
Aqueous Medium ◽  
High Selectivity ◽  
Photophysical Properties ◽  
Aqueous Media ◽  
Medium Ph ◽  
Absorption And Fluorescence Spectroscopy ◽  
High Fluorescence ◽  
Base Units

AbstractA new Schiff base, 4-allylamine-N-(N-5-methylsalicylidene)-1,8-naphthalimide (1), has been designed and synthesized by combining a 1,8-naphthalimide moiety as a fluorophore and a Schiff base as a recognition group. Its photophysical properties were investigated by absorption and fluorescence spectroscopy, and this sensor exhibits a high fluorescence quantum yield of 0.75–0.91 inorganic solvents of different polarity. It also shows high selectivity for Cu2+ over other ions with fluorescence quenching in aqueous medium (pH=7.2). The reason for this phenomenon (fluorescence quenching) is attributed to the formation of a 1:1 complex between 1 and Cu2+ according to the Job plot and fluorescence titration. The sensor can be applied to the quantification of Cu2+ in a linear fashion from 0.5 to 5 μM with a detection limit of 0.23 μM. Additionally, the association constant (Ka) between Cu2+ and 1 is 1.328×106 M−1 in aqueous media.

Silica cross-linked nanoparticles encapsulating a phenothiazine-derived Schiff base for selective detection of Fe(iii) in aqueous media

2014 ◽  
Vol 2 (37) ◽  
pp. 6306-6312 ◽  
Author(s):  
Fangyuan Gai ◽  
Xiang Li ◽  
Tianlei Zhou ◽  
Xiaogang Zhao ◽  
Dongdong Lu ◽  
...  
Keyword(s):  
Schiff Base ◽  
Fluorescence Quenching ◽  
Aqueous Media ◽  
Selective Detection ◽  
Selective Determination ◽  
Design And Synthesis ◽  
Micellar Nanoparticles

This work demonstrates the design and synthesis of an ET-based fluorescence quenching chemosensor using silica cross-linked micellar nanoparticles as scaffolds to encapsulate EDDP for highly selective determination of Fe3+ in aqueous media.

scholarly journals Structural and Spectral Investigation of a Series of Flavanone Derivatives

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1298
Author(s):  
Anna Sykuła ◽  
Agnieszka Kowalska-Baron ◽  
Krystian Gałęcki ◽  
Paulina Błazińska ◽  
Elżbieta Łodyga-Chruścińska
Keyword(s):  
Schiff Base ◽  
Fluorescence Quenching ◽  
Schiff Bases ◽  
Computational Simulations ◽  
Serum Albumins ◽  
Theoretical Methods ◽  
Structural And Electronic Properties ◽  
Spectral Profiles ◽  
Chemical Descriptors ◽  
Static Mechanism

Four flavanone Schiff bases (E)-1-(2-phenylchroman-4-ylidene)thiosemicarbazide (FTSC) (1), N′,2-bis((E)-2-phenylchroman-4-ylidene)hydrazine-1-carbothiohydrazide (FTCH) (2), (E)-N’-(2-phenylchroman-4-ylidene)benzohydrazide (FHSB) (3) and (E)-N′-(2-phenylchroman-4-ylidene)isonicotinohydrazide (FIN) (4) were synthesized and evaluated for their electronic and physicochemical properties using experimental and theoretical methods. One of them, (2), consists of two flavanone moieties and one substituent, the rest of the compounds (1, 3, 4) comprises of a flavanone-substituent system in relation to 1:1. To uncover the structural and electronic properties of flavanone Schiff bases, computational simulations and absorption spectroscopy were applied. Additionally, binding efficiencies of the studied compounds to serum albumins were evaluated using fluorescence spectroscopy. Spectral profiles of flavanone Schiff bases showed differences related to the presence of substituent groups in system B of the Schiff base molecules. Based on the theoretically predicted chemical descriptors, FTSC is the most chemically reactive among the studied compounds. Binding regions within human and bovine serum albumins of the ligands studied are in the vicinity of the Trp residue and a static mechanism dominates in fluorescence quenching.

An On–Off–On Fluorescence Probe Based on Coumarin for Cu2+, Cysteine, and Histidine Detections

2019 ◽  
Vol 73 (7) ◽  
pp. 794-800 ◽  
Author(s):  
Ya Xie ◽  
Liqiang Yan ◽  
Jianping Li
Keyword(s):  
Schiff Base ◽  
Fluorescence Quenching ◽  
Metal Ions ◽  
Human Urine ◽  
Fluorescence Probe ◽  
Fluorescence Emission ◽  
Live Cells ◽  
Green Fluorescence ◽  
Great Reliability ◽  
Coordination Action

A simple coumarin-based Schiff base (probe L) was successfully developed. It showed strong green fluorescence emission at 527 nm with a 70.3% of fluorescence quantum efficiency (ΦF). However, after the addition of common metal ions, probe L can only combine with Cu2+ ions and displayed significant fluorescence quenching of > 96.2% (ΦF = 2.7%) due to the paramagnetic quenching action from Cu2+. Conversely, by the coordination action of cysteine (Cys) and histidine (His), the quenching fluorescence of the complex (L-Cu2+) between probe L and Cu2+ ions was recovered mostly because the Cys and His can usurp Cu2+ of L-Cu2+ and led to the liberation of probe L. Based on the fluorescence changes of probe L with the actions of Cu2+, Cys, and His, an on–off–on reversible fluorescence probe for sensitive and specific monitoring Cu2+, Cys, and His has been prepared. More importantly, the probe L and L-Cu2+ ensemble can be used, respectively, to test Cu2+ and Cys/His in live cells and human urine samples with great reliability.

Sign in / Sign up

Export Citation Format

Share Document