Bipyrene-Functionalized Graphene as a Turn-On Fluorescence Sensor for Manganese(II) Ions in Living cells

1,2-bis-(2-pyren-1-ylmethylamino-ethoxy) ethane (NPEY) was synthesized and brought to the surface of graphene nanosheets (GNs) via pi-pi stacking, which provided a simple and convenient route for processing turn-on fluorescent sensor by simply mixing the diluted aqueous solutions of both components. The synthesized NPEY modified graphene nanosheets (NPEY-GNs) not only allows good selectivity toward Mn2+ with the detection limit of 4.6 x 10(-5) M, but also shows turn-on response for Mn2+ both in vitro and in living cells. These sensing capabilities of NPEY-GNs in living cells make it a robust candidate for many biological fields, such as intracellular tracking, intracellular imaging, etc.