The McGill Physiology Virtual Lab

Blood Laboratory

Blood cell indices > Hemoglobin content determination
  A common method for measuring the hemoglobin content of blood makes use of an instrument known as a hemoglobinometer, which compares the colour of light passing through a hemolyzed blood sample with a standard colour. The results of the test are expressed as grams of hemoglobin per 100 ml of blood.
Examine the blood chamber below. It consists of two pieces of glass and a metal clip. Note that one of the pieces of glass has an H-shaped depression cut on it (the chamber glass), while the other piece is flat on both sides (the cover glass).
A drop of blood is placed on one side of the chamber glass.

The blood is stirred with the end of a hemolysis applicator until the blood appears as a transparent red rather than a cloudy liquid.
The hemolysis applicator has been dipped in a solution of saponin, which destroys the integrity of the red cell membrane, releasing the intracellular hemoglobin.
The cover glass is positioned on top of the blood plate and both are slid into the metal clip. The blood chamber is then slid into the slot on the side of the hemoglobinometer, and a reading is taken.

This photo shows the hemolyzed blood layer on the raised part of the glass chamber which is drawn slightly out of the clip. The cover glass on top is already well seated in the clip. The chamber glass with the blood sample will be pushed in completely: the blood sample will thus be "sandwiched" between the two pieces of glass and can be introduced in the hemoglobinometer.


When the blood chamber has been filled with hemolyzed blood, it is inserted in the slot on one side of the hemoglobinometer as shown in the accompanying image (insert, upper right). When the hemoglobinometer is held to the eye, and the light switch button is depressed, a green split field appears (insert, upper left). To practice taking a reading, click below and watch as the slide moves along, taking note of the concentration (in Grams of Hb/100 ml) when the two halves of the field appear to be the same shade of green.

  • You should have obtained a value of 17 grams Hb/100ml.
  • Note that the normal range of values for hemoglobin content is as follows:
Female: 11.5-15.5 g /dl
Male: 13.5-17.5 g/dl
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