title: Lead-ion potentiometric sensor based on electrically conducting microparticles of sulfonic phenylenediamine copolymer.
abstract: A potentiometric sensor to detect lead ions using newly synthesized conducting copolymer microparticles as an ionophore in self-supporting poly(vinyl chloride) membrane matrix plasticized with dioctyl phthalate was developed. The copolymer microparticles containing many ligating functional groups including amino, imino and sulfonic groups were synthesized by a chemical oxidative copolymerization of m-phenylenediamine (mPD) and p-sulfonic-m-phenylenediamine (SPD) in pure water. Due to the presence of -NH-, -N=, -NH2, and -SO3H ligating groups on the microparticles, a linear Nernstian response is obtained within a Pb(II) activity range from 1.00 × 10(-6) M to 1.00 × 10(-3) M. The Pb(II)-sensor containing the mPD/SPD (95/5) copolymer microparticles with the maximal electrical conductivity demonstrates a superior detection limit down to 1.26 × 10(-7) M, short response time to 14 s, and long lifetime of up to 4 months. The Pb(II)-sensor also exhibits a selective response to Pb(II) over 9 other metal ions and a pH independent plateau between 2.7 and 5.0. These advantages could make for a robust sensor performing credible analysis of Pb(II) concentration in real-world samples at trace levels.
authors.affiliation: Institute of Materials Chemistry, Key Laboratory of Advanced Civil Engineering Materials of the Ministry of Education, College of Materials Science and Engineering, Tongji University, 1239 Si-Ping Road, Shanghai 200092, China. huangmeirong@tongji.edu.cn
authors.forename: Mei-Rong
authors.initials: MR
authors.lastname: Huang
authors.forename: Yong-Bo
authors.initials: YB
authors.lastname: Ding
authors.forename: Xin-Gui
authors.initials: XG
authors.lastname: Li
mesh_terms: D000588:Amines / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004553:Electric Conductivity; D006863:Hydrogen-Ion Concentration; D007476:Ionophores / Q000737:chemistry; D007854:Lead / Q000032:analysis* / Q000737:chemistry; D008863:Microspheres; D011108:Polymers / Q000737:chemistry*; D011199:Potentiometry
chemical_list: D000588:Amines; D007476:Ionophores; D011108:Polymers; D007854:Lead