Single-Entity Electrochemistry (SEE) refers to the electroanalysis of an individual unit of interest. A unique feature of SEE is that it unifies multiple different branches of electrochemistry. Single-Entity Electrochemistry pushes the bounds of the field as it can measure entities on a scale of 100 microns to angstroms. Single-Entity Electrochemistry is important because it gives the ability to view how a single molecule, or cell, or "thing" affects the bulk response, and thus the chemistry that might have gone unknown otherwise. The ability to monitor the movement of one electron or ion from one unit to another is valuable, as many vital reactions and mechanisms undergo this process. Electrochemistry is well suited for this measurement due to its incredible sensitivity.  Single-Entity Electrochemistry can be used to investigate nanoparticles, wires, vesicles, nanobubbles, nanotubes, cells, and viruses, and other small molecules and ions. Single-entity electrochemistry has been successfully used to determine the size distribution of particles as well as the number of particles present inside a vesicle or other similar structures