Methoxyquinoline-diethylenetriamine conjugate as a fluorescent zinc sensor

Abstract

A 6-methoxyquinoline conjugated diethylenetriamine derivative, N,N''-bis(6-methoxy-2-quinolylmethyl)diethylenetriamine (6-MeOBQDIEN) has been synthesized and its fluorescent response toward zinc ion was investigated. In the presence of zinc ion, 6-MeOBQDIEN exhibits fluorescence (λ(ex) = 329 nm, λ(em) = 418 nm, φ = 0.039). The fluorescent intensity of the zinc complex of the compound is two times higher than the parent BQDIEN (φ = 0.021) under the same conditions. The crystal structure of 6-MeOBQDIEN-Zn complex shows that all five nitrogen atoms participate to the metal coordination in a distorted square-pyramidal geometry (τ = 0.145) with the aliphatic nitrogen in an apical position. Fluorescent microscopic analysis using 6-MeOBQDIEN reveals the zinc ion concentration change in living cells.

Sequential recognition of zinc ion and hydrogen sulfide by a new quinoline derivative with logic gate behavior

“…It is well known that many quinoline-based uorescent sensors have excellent selectivity for zinc sensing. [40][41][42][43][44][45][46][47] Therefore, the synthesized compound L was rstly used as a zinc probe. Subsequently the sequential complex L-2Zn was used as a hydrogen sulde sensor based on a cation removal sensing mechanism.…”

Quinoline benzimidazole-conjugate for the highly selective detection of Zn(ii) by dual colorimetric and fluorescent turn-on responses

“…Among these, quinoline is one of the promising classes of uorophore as it forms strong binding with metals and also reduces the molecular size by rigidication which becomes an important parameter to be used in probing the metal ions in biological systems. 18 In general, the uorescent properties of quinoline become quenched when substituted with amine due to photoinduced electron transfer (PET) processes. However, suppression of PET by the coordination between Zn 2+ and amine would enhance the uorescence, which in fact has been explored as a successful pathway for turn-on uorescence sensing mechanism.…”

Substituent-dependent fluorescent sensors for zinc ions based on carboxamidoquinoline

“…This duality helps to reduce the size of the sensors. 14 The most common fluorescent histological Zn 2+ stains originated from quinoline, 6-methoxy-(8-p-toluenesulfonamido)quinoline and its congeners, 15 are sulfonamidoquinoline derivatives that show substantial fluorescence enhancement upon coordination of Zn 2+ .…”