The present disclosure provides systems and methods for analyzing or identifying a target nucleic acid molecule. For example, a system of the present disclosure may comprise (a) a complex comprising a target nucleic acid molecule and a primer nucleic acid molecule, wherein the primer nucleic acid molecule comprises (i) a region that is complementary to a portion of the target nucleic acid molecule and (ii) an additional region that is non-complementary the target nucleic acid molecule, and (b) with said additional region having flown through a pore of a sensor, using said sensor to identify said additional region, thereby analyzing said target nucleic acid molecule. The sensor may be configured to detect one or more signals indicative of an impedance or impedance change in the sensor when the at least the portion of the target molecule is bound by the binding unit. The one or more signals may be usable to analyze or identify the target molecule.