UV-Vis., absorption spectroscopy are used to monitor the electron transfer reaction between the surfactant cobalt(III) complexes, cis-[Co(ip)2(C14H29NH2)2]3+, cis-[Co(dpq)2(C14H29NH2)2]3+ and cis-[Co(dpqc)2(C14H29NH2)2]3+ (ip = imidazo[4,5-f][1,10]phenanthroline, dpq = dipyrido[3,2-d:2’-3’-f]quinoxaline, dpqc = dipyrido[3,2-a:2’,4’-c](6,7,8,9-tetrahydro)phenazine, C14H29NH2=Tetradecylamine) and [Fe(CN)6]4- ion in liposome vesicles (DPPC) and ionic liquids ((BMIM)Br) were investigated at different temperatures under pseudo first order conditions using an excess of the reductant. The reactions were found to be second order and the electron transfer is postulated as outer-sphere. The rate constant for the electron transfer reactions were found to increase with increasing concentrations of ionic liquids. The effects of hydrophobicity of the long aliphatic double chains of these surfactant complex ions into liposome vesicles on these reactions have also been studied. Below the phase transition temperature of DPPC, the rate decreased with increasing concentration of DPPC, while above the phase transition temperature the rate increased with increasing concentration of DPPC. Kinetic data and activation parameters are interpreted in terms of an outer-sphere electron transfer mechanism. In all these media the S# values are found to be negative in direction in all the concentrations of complexes used indicative of more ordered structure of the transition state. This is consistent with a model in which the surfactant cobalt(III) complexes and Fe(CN)64- ions bind to the DPPC in the transition state. Thus, the results have been explained based on the self-aggregation, hydrophobic effect, and the reactants with opposite charge.

The interaction of cis-[Co(phen)2(TA)2](ClO4)3, a cationic surfactant complex (phen = 1-10 phenanthroline, TA= Tetradecylamine), with calf thymus DNA has been studied by physici-chemical techniques. The spectroscopic studies together with cyclic voltammetry and viscosity experiments support that the surfactant-cobalt(III) complex binds to calf thymus DNA (CT DNA) by intercalation through the aliphatic chain present in the complex into the base pairs of DNA. The presence of phenanthroline ligand with larger -frame work may also enhance intercalation. Besides the effect of binding of surfactant cobalt(III) complex to DNA in presence of -cyclodextrin has also studied. In presence of -cyclodextrin the binding occur through surface and (or) groove binding. The complex was investigated as one of the potential