title: Liquid chromatography-electrochemical detection of ferro- and ferricytochrome c at a chemically modified gold electrode.
abstract: Chemically modified electrodes, constructed by adsorption of 4,4'-dithiodipyridine onto a polyvinylferrocene-treated gold surface, were employed for the amperometric detection of cytochrome c following size-exclusion chromatography. The electrode response was nearly reversible, permitting quantitation both of the ferro-form of the protein at +0.15 V vs. Ag/AgCl and of the ferri-form at -0.15 V. The limit of detection for the reduced species was 3 pmol injected, and the response was linear over three orders of magnitude. Using the chemically modified electrode approach, cytochrome c monitoring was sufficiently selective that the compound could be determined in human plasma pretreated only by dilution and particulate filtration.
mesh_terms: D000818:Animals; D002417:Cattle; D002645:Chickens; D002853:Chromatography, Liquid; D003574:Cytochrome c Group / Q000032:analysis*; D004285:Dogs; D004563:Electrochemistry; D004566:Electrodes; D006046:Gold; D006801:Humans; D007202:Indicators and Reagents; D013045:Species Specificity; D013056:Spectrophotometry, Ultraviolet; D014413:Tuna
chemical_list: D003574:Cytochrome c Group; D007202:Indicators and Reagents; D006046:Gold