Design of a new dodecyl sulfate-selective electrode based on conductive polyaniline.
A new, simple, sensitive, low cost and rapid potentiometric method for direct determination of ultra trace amounts of sodium dodecyl sulfate (SDS) with a new DS(-)-selective electrode is reported. The electrode was prepared by electropolymerization of aniline in acidified DS- ion on the surface of a Pt electrode. The cyclic voltammetry (CV) was used for electropolymerization of polyaniline (PA) in the potential range of -200 to +1000 mV vs. Ag/AgCl. This sensor showed a Nernstian behavior (59.0 +/- 2.3 mV/decade) over a very wide linear range (1.0 x 10(-9)-3.0 x 10(-6) M) with a detection limit of 1.0 x 10(-9) M. The response time of the electrode was 15 s for 1.0 x 10(-7) M of analyte; the electrode can be used for 4 weeks without any major deviation. This electrode can be used in the pH range of 3.5-9.8. The selectivity of electrode to DS- over some organic, inorganic and anionic surfactants was investigated with the fixed primary ion method. The results show that the electrode is highly selective to DS- ion over other ions. The proposed electrode was applied to the determination of DS- in real samples.
Mousavi
Mir Fazlollah
MF
Department of Chemistry, Tarbiat Modarres University, Tehran, Islamic Republic of Iran. mousavim@modares.ac.ir
Shamsipur
Mojtaba
M
Riahi
Siavash
S
Rahmanifar
Mohammad Safy
MS
D000465:Algorithms; D000814:Aniline Compounds / Q000737:chemistry*; D002138:Calibration; D004563:Electrochemistry; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D012967:Sodium Dodecyl Sulfate / Q000032:analysis*; D013501:Surface-Active Agents / Q000032:analysis*
D000814:Aniline Compounds; D007202:Indicators and Reagents; D013501:Surface-Active Agents; D012967:Sodium Dodecyl Sulfate