Electrochemical Sensing Platform Based on Polyelectrolyte鈥揝urfactant Supramolecular Assemblies Incorporating Carbon Nanotubes

详细信息    查看全文

• 作者：M. Lorena Cortez ; Marcelo Ceol铆n ; Omar Azzaroni ; Fernando Battaglini
• 刊名：Analytical Chemistry
• 出版年：2011
• 出版时间：October 15, 2011
• 年：2011
• 卷：83
• 期：20
• 页码：8011-8018
• 全文大小：928K
• 年卷期：v.83,no.20(October 15, 2011)
• ISSN：1520-6882

文摘

The characterization and application of a polyelectrolyte鈥搒urfactant supramolecular assembly formed by poly(allylamine) and dodecyl sulfate (PA鈥揇S) on a screen-printed graphite electrode for the preparation of electrochemical sensing platforms are presented. The system was characterized by X-ray reflectometry (XRR) and grazing-incidence small-angle X-ray scattering (GISAXS) and tested with four benchmark electrochemical probes undergoing different electron-transfer mechanisms on carbon: ferrocyanide, hexaammineruthenium, ascorbic acid, and dopamine. The polyelectrolyte acts as a scaffold favoring the incorporation of the ferrocyanide, an ion oppositely charged to poly(allylamine). Also, its ability to incorporate carbon nanotubes (CNT) is presented. The composite material PA鈥揇S鈥揅NT is able to electrocatalyze the oxidation of dopamine, allowing its detection at micromolar levels in the presence of 100 times higher concentrations of ascorbate and it is shown to be stable, while XRR and GISAXS results confirm a lamellar structure with well-defined domains, not perturbed by the presence of the CNT. The dispersion is easily prepared in aqueous solution and could facilitate the processing of the CNT with an efficient loading and yielding a more robust carbon-based material for sensing applications.