A dual signal amplification strategy based on scanning electrochemical microscopy for DNA biosensing using a PEDOT-modified ultramicroelectrode and long self-assembled DNA concatemers

A PEDOT-modified Pt microelectrode was used in SECM for DNA biosensing and combined with long self-assembled DNA concatemers to realize dual signal amplification. The approach curve could also be plotted for tip location using this modified microelectrode with no impact on the catalytic effect so that both signal amplification and tip locating were achieved in one single tip. The detection limit of this method reached 0.076 fM, providing an ultra-sensitive DNA biosensing platform. Furthermore, this strategy could be applied in scanning a DNA chip, showing great potential in high-throughput bioanalysis with high sensitivity.