MilliporeSigma
  • Modified screen-printed ion selective electrodes for potentiometric determination of sodium dodecylsulfate in different samples.

Modified screen-printed ion selective electrodes for potentiometric determination of sodium dodecylsulfate in different samples.

Journal of AOAC International (2015-04-11)
Tamer Awad Ali, Gehad G Mohamed
ABSTRACT

Fabrication and general performance characteristics of novel screen-printed sensors for potentiometric determination of sodium dodecylsulfate (SDS) are described. The sensors are based on the use of ion-association complexes of SDS with cetylpyridinium chloride (electrode I) and cetyltrimethylammonium bromide (electrode II) as exchange sites in a screen-printed electrode matrix. Electrodes (I) and (II) show fast, stable, and near-Nernstian response for the mono-charge anion of SDS over the concentration range of 1×10(-2) - 5.8×10(-7) and 1×10(-2)-6.3×10(-7) mol/L at 25°C and the pH range of 2.0-9.0 and 2.0-8.0 with anionic slope of 57.32±0.81 and 56.58±0.65 mV/decade, respectively. Electrodes (I) and (II) have lower LODs of 5.8×10(-7) and 6.3×10(-7) mol/L and response times of about 8 and 13 s, respectively. Shelf life of 5 months for both electrodes is adequate. Selectivity coefficients of SDS related to a number of interfering cations, and some inorganic compounds were investigated. There were negligible interferences caused by most of the investigated species. The direct determination of 0.10-13.50 mg of SDS by electrodes (I) and (II) shows average recoveries of 99.96 and 99.85%, and mean RSDs of 0.83 and 1.04%, respectively. In the present investigation, both electrodes were used successfully as end point indicators for determination of SDS in pure pharmaceutical preparations and real spiked water samples. The results obtained using the proposed sensors to determine SDS in solution compared favorably with those obtained by the standard addition method.

MATERIALS
Product Number
Brand
Product Description

Supelco
Bis(2-ethylhexyl) phthalate, Selectophore
Supelco
Dibutyl phthalate, PESTANAL®, analytical standard
Supelco
Bis(2-ethylhexyl) phthalate, PESTANAL®, analytical standard
Sigma-Aldrich
Dibutyl phthalate, 99%
Sigma-Aldrich
Dioctyl phthalate, ≥99.5%
Dibutyl phthalate, European Pharmacopoeia (EP) Reference Standard
Supelco
Bis(2-ethylhexyl) phthalate, certified reference material, TraceCERT®, Manufactured by: Sigma-Aldrich Production GmbH, Switzerland
Supelco
Dibutyl phthalate, certified reference material, TraceCERT®, Manufactured by: Sigma-Aldrich Production GmbH, Switzerland
Supelco
3,5,6-Trichloro-2-pyridinol, PESTANAL®, analytical standard
Plastic additive 01, European Pharmacopoeia (EP) Reference Standard
Sigma-Aldrich
Sodium dodecyl sulfate solution, BioUltra, for molecular biology, 10% in H2O
Sigma-Aldrich
Sodium dodecyl sulfate, tested according to NF, mixture of sodium alkyl sulfates consisting mainly of sodium dodecyl sulfate
Sigma-Aldrich
Sodium dodecyl sulfate, ≥98.0% (GC)
Sigma-Aldrich
Sodium dodecyl sulfate, ≥90% ((Assay))
Sigma-Aldrich
Sodium dodecyl sulfate, BioReagent, suitable for electrophoresis, for molecular biology, ≥98.5% (GC)
Sigma-Aldrich
Sodium dodecyl sulfate, ReagentPlus®, ≥98.5% (GC)
Sigma-Aldrich
Hexadecyltrimethylammonium bromide, for molecular biology, ≥99%
Sigma-Aldrich
Hexadecyltrimethylammonium bromide, BioXtra, ≥99%
Sigma-Aldrich
Sodium dodecyl sulfate, BioXtra, ≥99.0% (GC)
Sigma-Aldrich
Hexadecyltrimethylammonium bromide, ≥98%
Sigma-Aldrich
Sodium phosphate dibasic dodecahydrate, BioXtra, ≥99.0% (T)
Sigma-Aldrich
Hexadecyltrimethylammonium bromide, ≥96.0% (AT)
Sigma-Aldrich
Hexadecyltrimethylammonium bromide, BioUltra, for molecular biology, ≥99.0% (AT)
Sigma-Aldrich
Sodium phosphate dibasic dodecahydrate, tested according to Ph. Eur.
Sigma-Aldrich
Di-n-octyl phthalate, ≥98.0% (GC)
Sigma-Aldrich
Sodium dodecyl sulfate, BioUltra, for molecular biology, ≥99.0% (GC)
Supelco
Hexadecyltrimethylammonium bromide, suitable for ion pair chromatography, LiChropur
Sigma-Aldrich
Sodium dodecyl sulfate, 92.5-100.5% based on total alkyl sulfate content basis
Supelco
Sodium dodecyl sulfate, dust-free pellets, suitable for electrophoresis, for molecular biology, ≥99.0% (GC)
Supelco
Di-n-octyl phthalate, certified reference material, TraceCERT®, Manufactured by: Sigma-Aldrich Production GmbH, Switzerland