Dual\nPhotoluminescence Emission Carbon Dots for Ratiometric\nFluorescent GSH Sensing and Cancer Cell Recognition

Abstract

We\ndeveloped a facile strategy for the fabrication of dual-emission\ncarbon nanodots (CDs) and demonstrated their applications for ratiometric\nglutathione (GSH) sensing and for differentiating cancer cells from\nnormal cells. Dual-emission CDs were synthesized using a simple hydrothermal\ntreatment of alizarin carmine as the carbon source, manifesting intriguing\ndual-emission behavior at 430 and 642 nm. With increasing GSH concentration,\nthe fluorescence band at 430 nm increased gradually, whereas that\nat 642 nm decreased slightly. With monitoring of the intrinsic ratiometric\nfluorescence variation (<i>I</i>_430nm/<i>I</i>_642nm), as-prepared CDs were developed as an\neffective platform for ratiometric fluorescent GSH sensing, with a\nlinear range of 1–10 to 25–150 μM and a detection\nlimit of 0.26 μM. More importantly, confocal fluorescent imaging\nof cancer cells and normal cells indicated that obtained CDs could\nbe implemented as an effective tool to visualize cancer cells with\noverexpressing GSH.