Free Energies of Electron Transfer, Electrochemical Properties, Electron Transfer Kinetic Theoretical and Quantitative Structural Relationship Studies of Cn @ X-[HbA] (HbA=Hemoglobin A; X= a- and b- Fumarate Crosslinked Hemoglobins (aXL & bXL))Nanostructure Complexes

The binding, release and oxidation of oxygen occur at the heme group iron ion. Hemoglobin oxidation-reduction studies have been previously performed using spectroelectrochemistry (SEC) and have provided insight into the hemoglobin electron transfer process and more specifically, into the heme group electronic factor and subunit interaction influences. In this study, the number of fullerene carbon atoms was used as an index to establish a relationship between the structures of hemoglobin A and a- and b-fumarate crosslinked hemoglobins, which were designated as HbA, aXL and aXL- [HbA] 1-3, respectively. These compounds represent the most well-known blood molecular systems and fullerenes (Cn, where n = 60, 70, 76, 82 or 86), which generated the following complexes: Cn@[HbA], A-1 to A-5; Cn@DXL-[HbA], B-1 to B-5 and Cn@EXL-[HbA], C-1 to C-5. The relationship between the carbon atom number and electron transfer free energies (aGet) were assessed using the Rehm-Weller equation for A-1 to A-5, B1 to B-5 and C-1 to C-5 supramolecular Cn@X- [HbA] (where HbA = hemoglobin A; X = a- and b-fumarate crosslinked hemoglobins (aXL & bXL)) and complexes 4-57, which possessed different electrochemical properties. Calculations were presented for the first Cn oxidation potentials (Ox.E1). The results were used to calculate the electron transfer first free energies (Get(1)) of supramolecular complexes A-1 to A-5, B1 to B-5 and C-1 to C- 5 for fullerenes C60 to C300. The first free activation energies and kinetic rate constants of the electron transfers, aG# et(n) (aGet(1) #) and ket, respectively, were also calculated in this study for A-1 to A-7, B1 to B-7 and C-1 to C-7 (compounds 4-24) in accordance with the Marcus theory.