title: Multilayer assembly of calf thymus DNA and poly(4-vinylpyridine) derivative bearing [Os(bpy)(2)Cl](2+): redox behavior within DNA film.
abstract: Polyelectrolyte multilayer (PEM) films containing polycationic osmium (Os) bipyridyl (bpy) complex-attached poly(4-vinylpyridine) (PVP) derivative [Os(bpy)(2)Cl](2+)-PVP (Os-PVP) and polyanionic calf thymus DNA (CT-DNA) on the surface of gold (Au) electrodes were prepared using a layer-by-layer self-assembly method, and their redox properties were studied. Os complex shows different redox behavior with CT-DNA film in comparison with other PEM film which is composed of ordinary polymers. A cyclic voltammetric study suggested that the outermost polyanionic DNA layer does not hinder the redox reaction of Os complex within the Os-PVP/CT-DNA multilayer film, which may be helpful to understand the electron transfer mechanism with the DNA film. For all the Os-complex-containing PEM layers studied, a diffusion-free electron transfer from the Os complex moieties in these films to the electrode surface was observed. An electrocatalytic oxidation of ascorbic acid (AA) by this DNA-containing PEM film-covered electrode was also proposed.
authors.affiliation: Energy Technology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Umezono 1-1-1, Tsukuba 305-8568, Japan. liuaihua@hotmail.com
authors.forename: Aihua
authors.initials: A
authors.lastname: Liu
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Anzai
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
mesh_terms: D015082:2,2'-Dipyridyl / Q000031:analogs & derivatives* / Q000737:chemistry; D000818:Animals; D002384:Catalysis; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D011145:Polyvinyls / Q000737:chemistry*
chemical_list: D009942:Organometallic Compounds; D011145:Polyvinyls; C019535:poly(4-vinylpyridine); D015082:2,2'-Dipyridyl; C085573:osmium bis(2,2'-bipyridine)chloride; D004247:DNA