What is the cyanmethemoglobin method for measuring hemoglobin (Hb) concentration?

By William Aird

Based on spectrophotometric measurement of cyanide derivative of hemoglobin.

Protocol includes:

  • Blood is mixed with a solution containing potassium cyanide and potassium ferricyanide (Drabkin’s solution).
  • The red blood cells are lysed, producing an evenly disturbed hemoglobin solution.
  • Potassium ferricyanide transforms hemoglobin into methemoglobin, and methemoglobin combines with potassium cyanide to produce hemiglobincyanide (cyanmethemoglobin).
  • Cyanmethemoglobin has a peak absorbance at 540 nm and is measured photometrically.
  • The absorbance is compared with that of the standard hemiglobincyanide solution by using a formula to obtain the amount of hemoglobin.