Provided herein are methods and systems pertaining to sequencing units of analytes using nanopores. In general, arresting constructs are used to modify an analyte such that the modified analyte pauses in the opening of a nanopore. During such a pause, an ion current level is obtained that corresponds to a unit of the analyte. After altering the modified analyte such that the modified analyte advances through the opening, another arresting construct again pauses the analyte, allowing for a second ion current level to be obtained that represents a second unit of the analyte. This process may be repeated until each unit of the analyte is sequenced. Systems for performing such methods are also disclosed.