title: The effect of cetyltrimethyl ammonium bromide on the electrochemical determination of thyroxine.
abstract: Electrochemical behavior of thyroxine at a polyvinylpyrrolidone modified carbon paste electrode in the presence of cetyltrimethyl ammonium bromide was described. Thyroxine underwent totally irreversible oxidation at this system and a well-defined peak at 0.42 V was obtained. The influence of various surfactants on the oxidation of thyroxine was examined by cyclic voltammetry. Chronocoulometry was also used to investigate the electrode process. In the range 2 x 10(-7) to 9 x 10(-6)mol/l, the thyroxine concentration was linear with the oxidation peak current and a low detection limit of 8 x 10(-8) mol/l was obtained for 5 min accumulation.
authors.affiliation: Department of Chemistry, Wuhan University, Wuhan 430072, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: He
authors.forename: Xueping
authors.initials: X
authors.lastname: Dang
authors.forename: Chengguo
authors.initials: C
authors.lastname: Hu
authors.forename: Shengshui
authors.initials: S
authors.lastname: Hu
mesh_terms: D002138:Calibration; D002244:Carbon / Q000032:analysis / Q000737:chemistry; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D009930:Organic Chemicals / Q000737:chemistry; D010084:Oxidation-Reduction; D011205:Povidone / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry; D013974:Thyroxine / Q000032:analysis* / Q000737:chemistry
chemical_list: D002593:Cetrimonium Compounds; D009930:Organic Chemicals; D013501:Surface-Active Agents; D002244:Carbon; D011205:Povidone; D013974:Thyroxine; D000077286:Cetrimonium