بخشی از متن مقاله Free Energies of Electron Transfer, Electrochemical Properties, Electron Transfer Kinetic Theoretical and Quantitative Structural Relationship Studies of Cn@X-[HbA] (HbA=Hemoglobin A; X= - and -Fumarate Crosslinked Hemoglobins (XL & XL)) Nanostructure Complexes :
سال انتشار : 2015
تعداد صفحات :24
The binding, release and oxidation of oxygen occur at the heme group iron ion. Hemoglobinoxidation-reduction studies have been previously performed using spectroelectrochemistry (SEC) andhave provided insight into the hemoglobin electron transfer process and more specifically, into theheme group electronic factor and subunit interaction influences. In this study, the number of fullerenecarbon atoms was used as an index to establish a relationship between the structures of hemoglobin Aand - and -fumarate crosslinked hemoglobins, which were designated as HbA, XL and XL-[HbA] 1-3, respectively. These compounds represent the most well-known blood molecular systemsand 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. Therelationship between the carbon atom number and electron transfer free energies (Get) were assessedusing 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 = - and -fumarate crosslinked hemoglobins (XL & XL))and complexes 4-57, which possessed different electrochemical properties. Calculations werepresented for the first Cn oxidation potentials (Ox.E1). The results were used to calculate the electrontransfer 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 electrontransfers, G#et(n) (Get(1)#) and ket, respectively, were also calculated in this study for A-1 to A-7, B1to B-7 and C-1 to C-7 (compounds 4-24) in accordance with the Marcus theory.