VOLUME 62 : 2014

A potentiometric sensor for sodium dodecylsulfate (SDS) was developed based on molecularly-imprinted polyaniline. The molecularly-imprinted polymer was synthesized through a potentiostatic electropolymerization of aniline monomer in the presence of the template SDS molecule at a constant potential of 0.8 V. The polymerization parameters determined the analytical performance of the polyaniline reagent phase. The optimized electropolymerization process provided a sensor with sensitivity of 45.54±6 mV/decade, working concentration range of 3×10^–6 M to 1×10^–2 M SDS, correlation coefficient (r²) of 0.993 and with a limit of detection 1×10^–5 M DS^–. The sensor response is reproducible with a mean RSD of 8.08% from 3×10^–6 M to 3×10^–3 M SDS. Selectivity studies using the fixed primary ion method proved the higher selectivity of the synthesized polymer for SDS over inorganic salts and fatty acid salts.

Keywords: molecularly imprinted polyaniline, potentiometric sensor, sodium dodecysulfate