What principle is the Coulter principle based on in hematology?

The Coulter principle is based on the detection of changes in cell electrical currents as cells pass through an electrical sensing zone. When a cell enters this zone, it displaces a volume of electrolyte solution, which results in a change in the electrical impedance. This change in impedance is directly proportional to the size of the cell. As a result, the Coulter counter can accurately count and size blood cells, making it a fundamental technique in hematology for analyzing blood samples.

This principle is crucial for the automated counting and sizing of red blood cells, white blood cells, and platelets, providing vital information for diagnosing various medical conditions. By leveraging electrical properties rather than physical attributes like viscosity or light scattering, the Coulter principle ensures precise and reliable results in blood analysis.