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How does an automated hematology analyzer count blood cells?

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blood analysis The physical and chemical properties of a sample of blood are examined during blood analysis. The examination of blood is important for the accurate diagnosis of disease.

An automated hematology analyzer counts blood cells by detecting changes in the electrical resistance of particles suspended in an electrolyte solution.1

The process functions as follows:
* Aperture Passage: The blood sample is passed through a narrow aperture within the machine.1
* Displacement: As each individual cell travels through this opening, it displaces the electrolyte solution.1
* Measurement: This displacement creates a fleeting change in electrical resistance. The analyzer measures these changes and correlates them to both the number and the size of the cells.1

This technology allows for rapid, precise quantification of red blood cells, white blood cells, and platelets as part of a complete blood count (CBC), with analyses typically completed in under a minute using only a small drop of blood.21