Modification of hemoglobin--ring opened dials.

The dialdehyde of ATP (o-ATP) has been synthesized and reacted with SFH. The conditions of reaction have been defined and the yields characterized. Close attention to the oxygenation state of SFH at the time of reaction is necessary; maintenance of the T-state is crucial as is low met-Hb concentrations. The o-ATP modified SFH has a near normal oxy-Hb affinity and a markedly prolonged, compared to SFH alone, intra-vascular retention. The effects of the modification on cooperativity and the specific binding sites are being evaluated. It appears that there is some loss of cooperativity by observation of the oxy-Hb dissociation curve.