title: Electroanalytical and naked eye determination of Cu(2+) ion in various environmental samples using 5-amino-1,3,4-thiadiazole-2-thiol based Schiff bases.
abstract: Novel polydentate Schiff bases 4-(5-mercapto-1,3,4-thiadiazol-2-ylimino)pentan-2-one (S1) and (2-(indol-3-yl)vinyl)-1,3,4-thiadiazole-2-thiol (S2) were synthesized and explored as Cu(2+) selective polymeric membrane electrodes (PME) using different plasticizers and anionic excluders. The potentiometric data revealed that the PME having the membrane composition (S2: NaTPB: TBP: PVC as 4: 2: 58: 36 (w/w; mg)) is shown to have good results. Thus the coated graphite electrode (CGE) with the same composition as the best PME was also fabricated and investigated as Cu(2+) selective electrode. It was found that CGE showed better response characteristics than PME with respect to low detection limit (1.2×10(-8)molL(-1)), near Nernstian slope (29.8±0.4mV decade(-1) of activity), wide working concentration range (6.4×10(-8)-1.0×10(-1)molL(-1)), long shelf life (90days) and fast response time (9s). The CGE was used successfully as an indicator electrode for the potentiometric determination of Cu(2+) ion against EDTA and also used to quantify Cu(2+) ion in soil, water, medicinal plants, vegetables and edible oil samples. The Schiff base S2 is used as chemosensor for the selective determination of Cu(2+) ion.
authors.affiliation: Department of Chemistry, Indian Institute of Technology-Roorkee, Roorkee 247 667, India.
authors.forename: Koteswara Rao
authors.initials: KR
authors.lastname: Bandi
authors.forename: Ashok Kumar
authors.initials: AK
authors.lastname: Singh
authors.forename: Anjali
authors.initials: A
authors.lastname: Upadhyay
mesh_terms: D002138:Calibration; D003124:Colorimetry; D003300:Copper / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods*; D006108:Graphite; D006863:Hydrogen-Ion Concentration; D017736:Ion-Selective Electrodes; D007477:Ions / Q000032:analysis; D007700:Kinetics; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D009821:Oils / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D011199:Potentiometry / Q000379:methods*; D012545:Schiff Bases / Q000138:chemical synthesis / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet; D013830:Thiadiazoles / Q000737:chemistry*; D013997:Time Factors; D014675:Vegetables / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D007477:Ions; D008567:Membranes, Artificial; D009821:Oils; D012545:Schiff Bases; D012987:Soil; D012996:Solutions; D013830:Thiadiazoles; D014867:Water; C058949:1,3,4-thiadiazole; D006108:Graphite; D003300:Copper
keywords: Electroanalytical methods; Electrochemical sensors; Ion selective electrodes; Potentiometry