Amino-1,8-naphthalimide-based fluorescent chemosensors for Zn(II) ion

Self-Associated 1,8-Naphthalimide as a Selective Fluorescent Chemosensor for Detection of High pH in Aqueous Solutions and Their Hg2+ Contamination

“…At lower pH, the inclusion of nitrogen atoms (imine nitrogen of triazine moiety) in the hydrogen bonding of the dimer assembly, shown in Figure 1 , blocks PET to 1,8-naphthalimide and hence opens fluorescence emission like the related reported 1,8-naphthalimides analogs [ 77 , 78 , 79 , 80 , 81 ]. In contrast, the probe responds to higher pH by an on-off response due to the deprotonation of NH 2 and concomitant switching of PET, Scheme 2 .…”

Fluorescence sensing and bioimaging of Cu(ii) ions using amino-1,8-naphthalimide-based small-molecule chemosensors

“…2 Contamination of food and water due to industrial discharges, which majorly comprise heavy metal ions and other impurities, generates toxic effects on human health and adverse impact on the environment. 3 Metallic products have become part of our daily life in various forms like utensils, cookware, deodorants, drinking water supplies, etc. which further facilitates the bioaccumulation of heavy metal ions in the human body apart from industrial drainage.…”

“…4 Aberrations in the normal levels of essential metal ions and intake of hazardous metal ions cause a wide range of diseases and permanent injuries to the organs like kidney failure, stomach ulcers, hypertension, bone lesions, lung dysfunction, and cardiovascular and neuro-disorders. 3,5 Therefore, maintaining tight control over the homeostasis of metal ions is of paramount interest to maintain proper health and environmental sustainability.…”

“…21–25 Owing to the outstanding features such as facile synthesis, tunable structures and functions, and interesting photophysical properties including large Stokes shift, high photo-stability, relatively high quantum yield, and solvent-dependent emission characteristics, amino-1,8-naphthalimide ( Nap ) dyes have evolved as a favorite fluorophore and thus, a large number of fluorescence sensors have been developed and successfully employed for sensing different analytes. 3,26,27 Amino-1,8-naphthalimides ( Naps ) are a classical heterocyclic ‘push–pull’ class of fluorophores that absorb and emit in the visible region. Nap derivatives are generally highly emissive due to the efficient internal charge transfer (ICT) transition from the amino group to the electron-deficient imide moiety.…”

“…Nap derivatives are generally highly emissive due to the efficient internal charge transfer (ICT) transition from the amino group to the electron-deficient imide moiety. 3,26 Moreover, the fluorescence emission intensity of Naps highly depends on the position of the amino group on the naphthalene unit. 3-Amino-based Naps are less emissive than 4-amino-based Naps due to the less efficient ICT transitions.…”