title: Electrochemical investigation into the redox activity of Fe(II)/Fe(III) in the presence of nicotine and possible relations to neurodegenerative diseases.
abstract: The biological relevance of Fe(II)/Fe(III) is becoming evermore apparent, especially in relation to its potential role in the progression of neurodegenerative diseases such as Parkinson's and Alzheimer's disease. The reported relationship between smoking and a reduced incidence of neurodegenerative disorders prompted this work. In order to investigate whether nicotine can interact with iron, we have studied the electrochemical behaviour of a Fe(II)/Fe(III) redox couple in the presence of nicotine. Solubility issues and lack of available nonreacting salts of nicotine necessitated studies being conducted at low pH values. Cyclic voltammetry experiments revealed a definite alteration in the electrochemical behaviour of the Fe(II)/Fe(III) redox couple suggesting the capability of nicotine to complex with free iron and, hence, reduce its reactivity. This is evident from a slower rate of heterogeneous electron transfer, ks, and a shift from reversible to quasi-reversible behaviour, as characterised from the diffusion coefficient (D), the full width half maximum (FWHM), DeltaEp and Ef. Additional complexation titrations, pH ranging from 1 to 7, confirm a weak complexation reaction occurring between Fe(III) and nicotine.
authors.affiliation: Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163-AC, A-1060 Vienna, Austria.
authors.forename: Mary H
authors.initials: MH
authors.lastname: Bridge
authors.forename: Edna
authors.initials: E
authors.lastname: Williams
authors.forename: Michael E G
authors.initials: ME
authors.lastname: Lyons
authors.forename: Keith F
authors.initials: KF
authors.lastname: Tipton
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Linert
mesh_terms: D004563:Electrochemistry; D004579:Electron Transport; D005290:Ferric Compounds / Q000737:chemistry*; D005296:Ferrous Compounds / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007501:Iron; D019636:Neurodegenerative Diseases / Q000378:metabolism; D009538:Nicotine / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D005290:Ferric Compounds; D005296:Ferrous Compounds; D009538:Nicotine; D007501:Iron