title: A highly selective potentiometric sensor of molybdate based on a mu-oxo-bridged manganeseporphyrin dimer.
abstract: A novel high-selective potentiometric sensor for molybdate was prepared with a PVC membrane combining mu-oxo-bis[5,10,15,20-tetra(p-methylphenyl)porphinatomanganese(III)] [[Mn(p-Me)TPP](2)O] as an electroactive material and 2-nitrophenyl octyl ether (o-NPOE) as a plasticizer in the percentage ratio of 3:65:32, [Mn(p-Me)TPP](2)O:o-NPOE:PVC (w:w). The sensor exhibited a linear response with a Nernstian slope of 30.5 mV per decade within a concentration range of 2.1 x 10(-6) to 1.0 x 10(-1) M MoO4(2-), with a working pH range from 5.0 to 12.5, and a fast response time of less than 15 s. The electrode showed improved selectivity toward molybdate with respect to common coexisting anions compared to monometalloporphyrin counterparts. Several electroactive materials and solvent mediators were compared and the experimental conditions were optimized. The sensor is preliminary applied to the assay of MoO4(2-) in corrosion inhibitor samples with satisfactory results.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry & Chemical Engineering, Hunan University, Changsha 410082, P.R. China.
authors.forename: Zheng-Hui
authors.initials: ZH
authors.lastname: Fang
authors.forename: Zhi-Xiang
authors.initials: ZX
authors.lastname: Han
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Zhang
authors.forename: Guo-Li
authors.initials: GL
authors.lastname: Shen
authors.forename: Ru-Qin
authors.initials: RQ
authors.lastname: Yu
mesh_terms: D019281:Dimerization; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D017736:Ion-Selective Electrodes; D008345:Manganese / Q000737:chemistry*; D017895:Manganese Compounds / Q000032:analysis*; D008567:Membranes, Artificial; D008665:Metalloporphyrins / Q000737:chemistry*; D008982:Molybdenum / Q000737:chemistry*; D010087:Oxides / Q000032:analysis*; D011143:Polyvinyl Chloride / Q000737:chemistry; D011199:Potentiometry / Q000379:methods; D012997:Solvents / Q000737:chemistry
chemical_list: D017895:Manganese Compounds; D008567:Membranes, Artificial; D008665:Metalloporphyrins; D010087:Oxides; D012997:Solvents; C516990:mu-oxo-bis(5,10,15,20-tetra(p-methylphenyl)porphinatomanganese(III)); C044659:molybdate; C048856:permanganic acid; D008345:Manganese; D008982:Molybdenum; D011143:Polyvinyl Chloride