A nanosensor for detecting molecule characteristics includes a membrane having an opening configured to permit a charged molecule to pass but to block a protein molecule attached to a ligand connecting to the charged molecule, the opening being filled with an electrolytic solution. An electric field generator is configured to generate an electric field relative to the opening to drive the charged molecule through the opening. A sensor circuit is coupled to the electric field generator to sense current changes due to charged molecules passing into the opening. The current changes are employed to trigger a bias field increase to cause separation between the ligand and the protein to infer an interaction strength.