blood hemoglobin level hemoglobin concentration 2011-01-05T08:36:48Z CMO:0000506 The amount of hemoglobin, the red oxygen-carrying pigment of erythrocytes, in a specified volume of blood, as calculated from the optical density of a solution of lysed red cells in which hemoglobin has been converted to cyanomethemoglobin and measured with a spectrophotometer. VT:0001588 clinical_measurement_ontology hemoglobin absorbance mshimoyama true