ESIPT and CHEF based highly sensitive and selective ratiometric sensor for Al3+ with imaging in human blood cells. (3rd September 2015)

• Record Type: Journal Article
• Authors: Das, Sangita; Goswami, Shyamaprosad; Aich, Krishnendu; Ghoshal, Kakali; Quah, Ching Kheng; Bhattacharyya, Maitree; Fun, Hoong-Kun
• Is Part Of: New journal of chemistry. Volume 39:Number 11(2015:Nov.)
• Page Start: 8582
• Page End: 8587
• Publication Date: 2015-09-03
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c5nj01468a
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : We have synthesised a probe for the fluorescence ratiometric detection of Al 3+ . This probe can be used to image Al 3+ in living cells. Abstract : Based on excited state intramolecular proton transfer (ESIPT) and chelation enhanced fluorescence (CHEF) mechanisms, a new fluorescence ratiometric probe for Al 3+ was designed and synthesized, and its structure was confirmed through single crystal X-ray study. This probe is capable of showing excited state intramolecular proton transfer through two different pathways. The introduction of Al 3+ in a mixed aqueous solution with the probe results in an abrupt change in the photophysical properties of the probe. A ratiometric emission profile was observed in the presence of Al 3+ . Interestingly, the presence of other metal ions (especially trivalent ions, e.g. Fe 3+, Cr 3+, Ga 3+ and In 3+ ) do not perturb the fluorescence intensity of the probe (except Cu 2+ and Pb 2+, where slight changes were noticed). This indicates that the probe shows high affinity towards Al 3+ . The ratiometric sensing phenomenon may be explained by the presence of two different mechanisms, namely, excited state intramolecular proton transfer and chelation induced enhanced fluorescence, which are demonstrated by the probe in presence of Al 3+ in the excited state. The complexation of the probe with Al 3+ inhibits excited state intramolecular proton transfer while the chelation induced enhanced fluorescence mechanism becomes dominant. The probe efficiently detected the cellular uptake of Al 3+, which is demonstrated here with human blood-cell imaging. Moreover, the detection limit was found to be 6.72 × 10 −8 M.