A DNAzyme-rGO coupled fluorescence assay for T4PNK activity in vitro and intracellular imaging

Phosphorylation of DNA caused by T4 PNK is an important regulatory process that associated with many cellular events and diseases. Here, we proposed a DNAzyme-rGO coupled fluoresence method for T4 PNK detection. Under the optimal conditions, the approach exhibits high sensitivity with a detection limit of 0.001 U/mL, and there was a reliable linear relationship between fluorescence intensity and T4 PNK concentration in the range of T4 PNK from 0.001 U/mL - 5 U/mL. Then, this method was used for kinetic analysis and effectors screening from natural compounds. Finally, the method was applied to monitor activity of T4 PNK in vitro and intracellular imaging of T4 PNK. In summary, this sensitive and specific sensing platform for T4 PNK assay can be hopefully used for clinical diagnosis, prognosis evaluation and targeted drug screening.