The Split Primer Ligation-triggered 8-17 DNAzyme Assisted Cascade Rolling Circle Amplification for High Specific Detection of Liver Cancer-involved mRNAs: TK1 and c-myc

Simultaneous detection of various intracellular biomarkers is promising for early diagnosis and treatment of cancer. Herein, we develop a novel method for high specific and ultrasensitive detection of liver cancer cell-involved mRNAs: TK1 and c-myc based on the split primer ligation-triggered 8-17 DNAzyme assisted cascade rolling circle amplification. Only two targets exist simultaneously, can trigger the rolling circle amplification to improve the accuracy and sensitivity. Meanwhile, an electrochemical molecular beacon, based on the host-guest recognition between ferrocene groups and cucurbit urils [7] (CB[7]/Fc-MB), is used to cause a "turn-off" electrochemical signal which is decreased by disrupting its hairpin structure. Under the optimal conditions, the detection limit of TK1 and c-myc mRNA is as low as 0.06 nM. Moreover, this method can be used to detect the TK1 and c-myc mRNA in HepG2 cells and distinguish between cancer cells and their normal cells, proving that the method has the potential to detect the variation of biomarkers in vivo.