A highly selective OFF-ON fluorescent sensor for D-3-HB in aqueous solution and living cells

Abstract A novel probe, 4-(2-hydroxybenzylicene)thiosemicarbazide ( 1 ), was synthesized and shown a peculiar OFF-ON fluorescent response to D-3-HB in Tris-HCl (pH = 6.0). The probe 1 has exhibited a selective and sensitive response to the D-3-HB over other common metal ions, anions and amino acids. Moreover the mechanism was confirmed by 1 H NMR and ESI–MS. Furthermore, this probe 1 successfully applied to bioimaging, demonstrating its value of practical applications in biological systems.