PREPARATIVE AND ANALYTICAL APPLICATIONS OF IMMOBILIZED HEMOGLOBIN

New applications of haemoglobin immobilized on Sepharose 4B are propos ed for the removal of cell-free, potentially toxic haemoglobin from ei ther natural biological specimens or artificial haemoglobin-containing systems (e.g., blood substitutes, haemosomes) to be employed for biom edical purposes. In a model study, an affinity column of immobilized h aemoglobin was used to remove free haemoglobin from blood serum in whi ch controlled haemolysis had been induced. The affinity column retains all the free haemoglobin, does not retain the haemoglobin-haptoglobin complex(es) and leaves the composition of the serum samples unaltered . When immobilized met-haemoglobin is used, haem is transferred readil y to albumin, with which it forms a complex. This observation on the o ne hand shows that immobilized oxyhaemoglobin should be preferred for preparative purposes, and on the other opens the way to the characteri zation of the haem transfer reaction to albumin by means of immobilize d met-haemoglobin. This reaction is difficult to study in solution owi ng to the overlap of the met-haemoglobin and methaemalbumin spectra.