Human Hemoglobin Conjugated to Carboxylate Dextran as a Potential Red Blood Cell Substitute. I. Further Physico-Chemical Characterization

Abstract

In a previous paper [1], we described the preparation of a conjugate by reaction of benzene tetracarboxylate-substituted dextran (dex-BTC) with oxyhemoglobin. The first biological experiments carried out on animals [2] showed that a solution of this type of product could be regarded as an oxygen-carrying fluid.

The physico-chemical properties of this conjugate have been further characterized in view of its potential application in clinical experiments. Its molecular size distribution and the fraction of intramolecularly cross-linked hemoglobin were determined by elution on various types of chromatographic columns. Moreover the conjugate's oxygen-binding properties were studied in the presence of effectors and of Clions, and the results showed that the allosteric site and the Val 1α residues of conjugated hemoglobin were occupied by dex-BTC. Finally, the fractions obtained after gel filtration exhibited a similar P₅₀ whatever their molecular sizes. So far, all the results obtained are compatible with the use of the conjugate solution as a blood substitute.