A reference control for cell by cell analysis on flow cytometric analyzers contains cellular analogs made of permeated blood cells containing therein aggregated intracellular proteins and preserved antigenic sites thereof, having cellular membrane permeable to antibodies and a suspension medium. The reference control is frozen after being prepared and thawed prior to use. The cellular analogs further contain a fluorescence marker therein. Further disclosed are a method of making the reference control and a method using the reference control, as an internal or stand-alone control, for measurements of cellular hemoglobin and cellular hemoglobin variant of a blood sample.
