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How is hemoglobin concentration measured in a blood sample?

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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.

To measure hemoglobin concentration in a blood sample, the blood is first diluted and the red blood cells are broken down to create a clear red solution. Because hemoglobin contains a highly colored pigment that interferes with the passage of light, a photoelectric instrument is then used to measure the absorbance of transmitted light. The hemoglobin concentration is calculated based on this measurement.1

In clinical settings, such as when a patient is donating blood, a quick finger-prick test may be performed to assess hemoglobin levels, as low counts can indicate anemia. While automated hematology analyzers are commonly used for a complete blood count to quantify various blood components, the specific photometric method described remains a standard approach for determining hemoglobin concentration.231