Novel PVC-membrane potentiometric sensors based on a recently synthesized sulfur-containing macrocyclic diamide for Cd2+ ion. Application to flow-injection potentiometry.
A new sulfur-containing macrocyclic diamide, 1,15-diaza-3,4,12,13-dibenzo-5,11-dithia-8-oxa-1,15-(2,6-pyrido)cyclooctadecan-2,14-dione, L, was synthesized, characterized and used as an active component for fabrication of PVC-based polymeric membrane (PME), coated graphite (CGE) and coated silver wire electrodes (CWE) for sensing Cd(2+) ion. The electrodes exhibited linear Nernstian responses to Cd(2+) ion in the concentration range of 3.3 x 10(-6) to 3.3 x 10(-1)M (for PME, LOD=1.2 x 10(-6)M), 2.0 x 10(-7) to 3.3 x 10(-1)M (for CWE, LOD=1.3 x 10(-7)M) and 1.6 x 10(-8) to 1.3 x 10(-1)M (for CGE, LOD=1.0 x 10(-8)M). The CGE was used as a proper detection system in flow-injection potentiometry (FIP) with a linear Nernstian range of 3.2 x 10(-8) to 1.4 x 10(-1)M (LOD=1.3 x 10(-8)M). The optimum pH range was 3.5-7.6. The electrodes revealed fairly good discriminating ability towards Cd(2+) in comparison with a large number of alkali, alkaline earth, transition and heavy metal ions. The electrodes found to be chemically inert, showing a fast response time of <5s, and could be used practically over a period of about 2-3 months. The practical utility of the proposed system has also been reported.
Shamsipur
Mojtaba
M
Department of Chemistry, Razi University, Kermanshah, Iran. mshamsipur@yahoo.com
Dezaki
Abbas Shirmardi
AS
Akhond
Morteza
M
Sharghi
Hashem
H
Paziraee
Zahra
Z
Alizadeh
Kamal
K
D002104:Cadmium / Q000032:analysis*; D003958:Diamide / Q000138:chemical synthesis* / Q000737:chemistry; D004566:Electrodes / Q000592:standards; D006863:Hydrogen-Ion Concentration; D047028:Macrocyclic Compounds / Q000737:chemistry*; D011143:Polyvinyl Chloride; D011199:Potentiometry / Q000295:instrumentation / Q000379:methods*; D013455:Sulfur
D047028:Macrocyclic Compounds; D002104:Cadmium; D003958:Diamide; D013455:Sulfur; D011143:Polyvinyl Chloride