RBCs labeled at two biotin densities permit simultaneous and repeated measurements of circulating RBC volume.
Mock DM, Lankford GL, Widness JA, Burmeister LF, Kahn D, Strauss RG. RBCs labeled at two biotin densities permit simultaneous and repeated measurements of circulating RBC volume. Transfusion. 2004 Mar; 44(3):431-7.