BODIPY-functionalized gold nanoparticles as a selective fluoro-chromogenic chemosensor for imaging Cu2+ in living cells

A new fluoro-chromogenic chemosensor based on BODIPY-functionalized gold nanoparticles 1 is prepared. Addition of Cu2+ ions to aqueous solutions of 1 gave an instantaneous color change along with a blue-shift of the absorption band and quenching of the emission spectrum at room temperature. The chemosensor 1 exhibits a high affinity and selectivity for Cu2+ over competing metal ions tested. Moreover, confocal microscopy experiments establish that 1 can be used for detecting Cu2+ levels within living cells.