Device for the analysis of nucleic acid molecules

A device, comprising:

• a plate having a top surface and a bottom surface, the plate comprising a well formed therein, the well extending along an axis into the plate from the top surface to a base of the well, the base being defined by the plate, the well opening at the top surface, the axis being normal to the bottom surface and the base of the well closing the well at the bottom surface;
• a nucleic acid molecule disposed in the well, the nucleic acid molecule comprising a first end, the first end being anchored to a surface at or proximate to the base;
• a bead disposed in the well, the nucleic acid molecule comprising a second end, the bead being anchored to the second end,
• an actuator configured to cause the bead to move relative to the bottom surface along the axis within a portion of the well along the axis, the portion of the well having a cross-sectional area measured perpendicular to the axis, the cross-section area increasing as a distance from the base to the cross-section area increases;
• and
• a sensor configured to measure an impedance of the well, the impedance depending on a distance between the bead and the base.