Redox titrations

The dinitrogenase component proteins of the conventional Mo nitrogenase (MoFe protein) and of the alternative Fe-only nitrogenase (FeFe protein) were both isolated and purified from Rhodobacter capsulatus, redox-titrated according to the same procedures and subjected to an EPR spectroscopic comparison. In the course of an oxidative titration of the MoFe protein (Rc1Mo) three significant S ¼ 1/2 EPR signals deriving from oxidized states of the P-cluster were detected: (1) a rhombic signal (g ¼ 2.07, 1.96 and 1.

12p system191 01-06-2013 31 4   Download

Thecaa3-oxidase from Thermus thermophilushas been studied with a combined electrochemical, UV/VIS and Fourier-transform infrared (FT-IR) spectroscopic approach. In this oxidase the electron donor, cytochromec, is covalently bound to subunit II of the cytochrome c oxidase. Oxidative electrochemical redox titrations in the visible spectral range yielded a midpoint potential of )0.01 ± 0.01 V (vs. Ag/AgCl/3MKCl, 0.218 V vs. SHE¢) for the hemec.

9p research12 29-04-2013 49 3   Download

A novel metallobridged bis(b-cyclodextrin)s 2[bis(b-CD)s 2] was synthesized and characterized by means of 1 H NMR, IR, element analysis and redox iodometric titration. The fluorescence of metallobridged bis(b-CD)s 2 was weak compared with bis(b-CD)s 1because of the paramagnetism of copper (II) ions.

8p media19 06-03-2013 39 3   Download

Standards for standardization of reducing agents: K2Cr2O7 KIO3 Ce4+ Standards for standardization of oxidizing agents: Na2C2O4 Na2S2O3 Fe2+ (Mohr’s salt and Oesper’s salt) 4 .V. Auxiliary Oxidizing and Reducing Agents The analyte must be in a single oxidation state at the start of the titration. This can be achieved by using a preoxidation or pre-reduction step prior to analysis

25p doilan 26-01-2013 50 4   Download