Red blood cell volume can be independently determined in vitro using sheep and human red blood cells labeled at different densities of biotin.
Mock DM, Matthews NI, Strauss RG, Burmeister LF, Schmidt R, Widness JA. Red blood cell volume can be independently determined in vitro using sheep and human red blood cells labeled at different densities of biotin. Transfusion. 2009 Jun; 49(6):1178-85.