Lead(II) ion-selective electrode based on polyaminoanthraquinone particles with intrinsic conductivity.
A new polyvinylchloride membrane electrode was facilely prepared by using polyaminoanthraquinone (PAAQ) microparticles with an intrinsically electrical conductivity as a lead(II) ionophore. It is found that the electrode performance will significantly be improved with adding 1 wt% PAAQ microparticles and decreasing the membrane thickness. A 90 microm-thick membrane electrode consisting of PAAQ(salt):polyvinyl chloride:dioctylphthalate:sodium tetraphenylborate of 1:33:66:1 (wt) but without any traditional lead(II) ionophore achieved the optimal performance and exhibited a good Nernstian response for Pb(II) ions over a wide concentration range from 2.5 x 10(-6) to 0.1M with a slope of 28.9 mV/decade and a detection limit down to 776 nM. A reasonably short response time of 12s was revealed together with a long lifetime over a period of around 4 months in a wide pH range between 2.8 and 5.2. A fixed interference method indicated that the electrode has an excellent selectivity for lead(II) ion over alkali, alkaline earth and other heavy metal ions. The proposed electrode has been also found to be a powerful indicator electrode for potentiometric titration of Pb(II) ions with EDTA. The electrode can be used to accurately monitor the Pb(II) pollution in environmental waters.
Li
Xin-Gui
XG
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. adamxgli@yahoo.com
Ma
Xiao-Li
XL
Huang
Mei-Rong
MR
D000880:Anthraquinones; D017736:Ion-Selective Electrodes; D007476:Ionophores; D007854:Lead / Q000032:analysis*; D008567:Membranes, Artificial; D011108:Polymers; D011143:Polyvinyl Chloride; D014874:Water Pollutants, Chemical / Q000032:analysis
D000880:Anthraquinones; D007476:Ionophores; D008567:Membranes, Artificial; D011108:Polymers; D014874:Water Pollutants, Chemical; D007854:Lead; D011143:Polyvinyl Chloride