Free radical formation in reactions of lecithin with tetracyanoquinodimethane and tetracyanoethylene: relating the behavior of membrane-partitioned electrochemical cells to charge carrier using electron spin resonance.
Electron spin resonance spectra of solutions used to make conductive bilayer lipid membranes reveal that free radical formation is a precursor to membrane conductivity. Tetracyanoquinodimethane (TCNQ) forms a stable radical that self-aggregates in nonaqueous media, yet will diffuse into the aqueous phase as a monomer, potentially allowing interfacial exchange. Tetracyanoethylene (TCNE) will undergo hydrolysis via a radical intermediate, and the decomposition product is ESR silent. The electrochemical response of an electrochemical cell partitioned by a membrane modified by these dopants is ionic for TCNE. Although the mechanism is less clear for TCNQ, the role of a stable radical is clearly implicated.
Bender
C J
CJ
Department of Molecular Pharmacology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, 10461, USA.
D004563:Electrochemistry / Q000379:methods; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D005030:Ethylenes; D005609:Free Radicals / Q000737:chemistry / Q000378:metabolism; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism; D008567:Membranes, Artificial; D009570:Nitriles; D010713:Phosphatidylcholines
D005030:Ethylenes; D005609:Free Radicals; D008051:Lipid Bilayers; D008567:Membranes, Artificial; D009570:Nitriles; D010713:Phosphatidylcholines; C013703:tetracyanoquinodimethane; C003393:tetracyanoethylene