Dual signal amplification detection of m6A in serum of hepatocellular carcinoma patient by hybridization chain reaction and biocatalytic silver deposition

N6-methyladenosine (m6A) modification has an impact on RNA metabolism, and it has been demonstrated that m6A regulatory mechanisms play an important role in tumorigenesis and may serve as a potential hepatocellular carcinoma (HCC) marker. We constructed a dual-signal amplification strategy electrochemical biosensor based on biocatalytic silver deposition and hybridization chain reaction (HCR). Enzymatic silver deposition was performed on the electrode and detected by linear sweep voltammetry (LSV), which was used for the quantitative detection of m6A. There was a nice linear relationship between the current response values and the logarithm of the m6A RNA concentration in the range of 0.5 pM-5 μM, with a detection limit as low as 25 fM. The concentration of m6A detected by the sensor constructed in this work is consistent with the results obtained using commercial colorimetric immunoassays. What's more, the analysis of m6A RNA in the serum of HCC patients using the developed sensor showed the high analytical efficiency of the designed strategy, which was superior to three other markers (AFP, CEA, CA199). The constructed electrochemical biosensor has good sensitivity, specificity and reproducibility for the detection of m6A RNA, and the sensing platform has promising clinical applications in the diagnosis and prognosis of HCC.