A novel electrochemical biosensor for sensitive detection of telomerase activity based on structure-switching DNA

• This work developed a novel electrochemical method for simple, sensitive detection of Telomerase activity.
• It was based on telomerase amplification reaction and structure-switching DNA with ferrocene as the electroactive reporter.
• The assay possessed a very broad linear response range and a low detection limit of 100 Hela cells mL−1.
• In addition, this strategy allowed the sensing of telomerase activity using less working steps with good reproducibility and stability.

Telomerase has been considered to be an important tumor biomarker for early cancer diagnostics and a valuable target for therapy treatment. A novel electrochemical biosensor based on structure-switching DNA probe with ferrocene (Fc) as the electroactive reporter to detect telomerase activity was developed. The developed approach displayed desirable dynamic range from 102 to 6×104 Hela cells mL−1 with a detection limit of 100 Hela cells mL−1. This biosensor afforded good reproducibility, stability and simple operations. It provided a useful platform for practical use in quantitative telomerase activity assay for clinical applications. Telomerase inhibitor performance was also investigated and the results indicated the approach was suitable for telomerase inhibitor screening research.