Nanoscale Metal-Organic Framework-Hemoglobin Conjugates

A metal-organic framework (MOF)-protein conjugate, NH2-MIL-125(Ti)-hemoglobin [MIL-125(Ti)-Hb], was synthesized by a covalent postmodification strategy. The crystalline structure was maintained after chemical and protein modification. The content of grafted Hb was tuned by the stoichiometric ratio and reached 50wt% if the mass ratio of MIL-125(Ti)/Hb was 1:1.25 in the feed. The oxygen-transporting capacity of grafted Hb was kept, and the P-50 (the half O-2 pressure saturated with O-2) and Hill coefficients of the MIL-125(Ti)-Hb conjugate were found to be 22.9mmHg and 2.35, respectively, which are close to the respective values of free Hb. All the results indicate that the MIL-125(Ti)-Hb conjugate could be potentially used as an oxygen carrier.