A DNA sequencing device, and related methods, include a nanochannel sized to receive a DNA strand, a first electrode member exposed within the nanochannel, and a second electrode member exposed within the nanochannel and spaced apart from the first electrode to form an electrode gap. The second electrode member has a wedge shaped profile, and the first and second electrode members are operable to detect a change in electronic signal as the DNA strand passes through the electrode gap.