Heme on Polymer Matrixes

One of the major difficulties encountered in attempts to prepare 1 1 dioxygen-iron complexes which can desorb molecular oxygen, particularly oxygenated complexes of ferroheme, is the strong driving force toward the irreversible formation of the stable p-oxo ferriheme dimer, as represented in Eq. (11). The oxygenated 

Much recent work has been aimed at overcoming this problem, and two approaches have been partially successful. The first is the elegant steric approach porphyrins have been substituted in a fashin that inhibits dimerization. The second approach is to attach the heme complexes to a rigid polymer chain at low concentration so as to prevent two heme complexes from approaching each other in such a manner as to lead to dimerization. By these means a reversible reaction between molecular oxygen and metalloporphyrins has been achieved. 

In a classic experiment Wang97) reported the first synthetic oxygen carrier of Fe(II)porphyrin. He embedded the diethyl ester of ferroheme in a hydrophobic 

Hatano12 dispersed the ferroheme complex of poly(N-vinyl-2-methylimidazole) in fluid paraffin. He reported a reversible change in the visible spectra with respect to oxygen exposure. 

We have studied the oxygenation of ferroheme bound to a polymer ligand in the solid state98. The profiles of oxygen uptake by powders of polymer-heme complexes were measured by volumetry, as shown in Fig. 22. The heme complex embedded in the porous polymer matrix or in the poly(electrolyte) aggregate takes up 

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