Attempts to use carbodiimide (EDCI) to cross-link hemoglobin for transfusions

The polymerization of hemoglobin for use as a blood substitute and an oxygen carrier would be of interest because high-mol. wt macromolecules would have a longer vascular retention time than the monomer. We found that the molecules resulting from the treatment of hemoglobin with ethyldimethylaminopropylcarbodiimide did not have a higher mol. wt than free hemoglobin and also had a dissociation curve resembling that of monomers, but seemed more stable.