Substrate-free and label-free electrocatalysis-assisted biosensor for sensitive detection of microRNA in lung cancer cells.

We develop a substrate-free and label-free electrocatalysis-assisted biosensor for sensitive detection of microRNA using the iron-embedded nitrogen-rich carbon nanotubes (FeCN) as the catalytic elements. This biosensor exhibits excellent selectivity and high sensitivity with a detection limit of 8.53 × 10-16 M and a large dynamic range of 6 orders of magnitude. It can be further applied for accurate quantification of microRNA in lung cancer cells.