Polymerization of hemoglobin in sickle trait erythrocytes and lysates

We report 13C/1H magnetic double resonance measurements of polymer in sickle trait erythrocytes and direct measurements of solubility on lysates of these cells as a function of oxygen saturation. Polymerized hemoglobin is detected by these two methods only at oxygen saturation values below 60% and increases to 0.4 of the total hemoglobin at complete deoxygenation. These results confirm the validity of the NMR approach in determining values of polymer fraction. We have also found that the thermodynamic theory, that successfully describes gelation in sickle erythrocytes, does not predict the experimental results for sickle trait erythrocytes and must be refined.