title: Potentiometric measurement of ascorbate by using a solvent polymeric membrane electrode.
abstract: A novel potentiometric method for the determination of ascorbate is described in this communication. It is based on ascorbate oxidation with permanganate which is continuously released from the inner reference solution of a ligand-free tridodecylmethylammonium chloride (TDMAC)-based polymeric membrane ion selective electrode (ISE). The ISE potential determined by the activity of permanganate ions released at the sample-membrane phase boundary is increased with the consumption of permanganate. The proposed membrane electrode is useful for continuous and reversible detection of ascorbate at concentrations in 0.1M NaCl ranging from 1.0 x 10(-6) to 1.0 x 10(-3)M with a detection limit of 2.2 x 10(-7)M.
authors.affiliation: Laboratory of Environmental Chemistry, Yantai Institute of Coastal Zone Research for Sustainable Development, Chinese Academy of Sciences, P.O. Box 1488, Yantai 264003, PR China.
authors.forename: Huimin
authors.initials: H
authors.lastname: Guo
authors.forename: Tanji
authors.initials: T
authors.lastname: Yin
authors.forename: Qingmei
authors.initials: Q
authors.lastname: Su
authors.forename: Wei
authors.initials: W
authors.lastname: Qin
mesh_terms: D001205:Ascorbic Acid / Q000032:analysis* / Q000737:chemistry; D017736:Ion-Selective Electrodes; D010084:Oxidation-Reduction; D004364:Pharmaceutical Preparations / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011196:Potassium Permanganate / Q000737:chemistry*; D011199:Potentiometry; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D014675:Vegetables / Q000737:chemistry
chemical_list: D004364:Pharmaceutical Preparations; D011108:Polymers; D000644:Quaternary Ammonium Compounds; D012997:Solvents; D011196:Potassium Permanganate; C009543:tridodecylmethylammonium; D001205:Ascorbic Acid