Development of a cell permeable red-shifted CHEF-based chemosensor for Al(3+) ion by controlling PET.

Abstract A structurally modified quinazoline derivative ( L ) acts as highly selective chemosensor for Al 3 + ions in DMSO–H 2 O (1:9, v/v) over the other competitive metal ions. L shows a red shifted fluorescence after the addition of Al 3 + ions and later the further fluorescence enhancement is due to chelation enhanced fluorescence (CHEF) through inhibition of photoinduced electron transfer (PET). This probe ( L ) detects Al 3 + ions as low as 9 nM in DMSO–H 2 O (1:9, v/v) at biological pH. The non-cytotoxic probe ( L ) can efficiently detect the intercellular distribution of Al 3 + ions in living cells under a fluorescence microscope to exhibit its sensible applications in the biological systems.