Highly selective OFF-ON fluorescent sensor for D-3-HB in aqueous

Diabetic ketoacidosis ( DKA ) is the most common hyper-glycemic emergency in patients with diabetes, and it was caused by too much ketones. Among the total ketone body, D-3-hydroxybutyric acid ( D-3-HB ) is the major, nearly 78%. So the detection of serum D-3-HB has been a routine marker for diagnosis of diabetic ketoacidosis. Fluorescent detection is the most efficient method, operational simplicity, low cost, real time monitoring and high sensitivity. Here, Two novel probe, 4-(2-hydroxybenzylicene)thiosemicarbazide ( 1 ) and 4-(1H- imidazo[4,5-f][1,10]- phenanthrolin-2-yl)phenol ( 2 ), were synthesized and shown a peculiar OFF-ON fluorescent response to D-3-HB in aqueous. The probe 1 & 2 have 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 1H-NMR and ESI-MS. Furthermore, this probe 1 successfully applied to bioimaging, demonstrating its value of practical applications in biological systems.