Effect of DNA on the rate of electron transfer reactions between non-intercalated reactants: kinetic study of the reactions [Ru(NH3)(5)pz](2+)+[Co(C2O4)(3)](3-) and [Ru(NH3)(5)py](2+)+[Co(NH3)(4)pzCO(2)](2+) in aqueous solutions in the presence of DN

摘要

The kinetics of the electron transfer reactions between pentaammine(pyrazine)ruthenium(II), [Ru(NH3)(5)pz](2+) and tris(oxalate)cobalt(III), [Co(C2O4)(3)](3-) and pentaammine(pyridine)ruthenium(II), [Ru(NH3)(5)py](2+) and tetraammine(pyrazinecarboxylate)cobalt(III), [Co(NH3)(4)pzCO(2)](2+) have been studied in aqueous solutions of DNA over the concentration ranges 0 to 2.46 x 10(-3) mol dm(-3) and 1.23 x 10(-4) to 1.00 x 10(-3) mol dm(-3), respectively. The results are interpreted on the basis of a modified pseudophase model which takes into account the anticooperative character of the binding of the cationic reactants to DNA. [References: 50]