Simultaneous detection of cadmium, copper, and lead using a carbon paste electrode modified with carbamoylphosphonic acid self-assembled monolayer on mesoporous silica (SAMMS)

Wassana Yantasee, Yuehe Lin, Glen E. Fryxell, Brad J. Busche

Research output: Contribution to journalArticle

136 Scopus citations


A new sensor was developed for simultaneous detection of cadmium (Cd 2+), copper (Cu2+), and lead (Pb2+), based on the voltammetric response at a carbon paste electrode modified with carbamoylphosphonic acid (acetamide phosphonic acid) self-assembled monolayer (SAM) on mesoporous silica (Ac-Phos SAMMS). The adsorptive stripping voltammetry (AdSV) technique involves preconcentration of the metal ions onto Ac-Phos SAMMS under an open circuit, then electrolysis of the preconcentrated species, followed by a square wave potential sweep towards positive values. Factors affecting the preconcentration process were investigated. The voltammetric responses increased linearly with the preconcentration time from 1 to 30min or with metal ion concentrations ranging from 10 to 200ppb. The responses also evolved in the same fashion as adsorption isotherm in the pH range of 2-6. The metal detection limits were 10ppb after 2min preconcentration and improved to 0.5ppb after 20min preconcentration.

Original languageEnglish (US)
Pages (from-to)207-212
Number of pages6
JournalAnalytica Chimica Acta
Issue number2
StatePublished - Jan 30 2004



  • Adsorptive stripping voltammetry
  • Carbamoylphosphonic acid
  • Carbon paste electrode
  • Chemically modified electrode
  • Self-assembled monolayer

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Environmental Chemistry
  • Spectroscopy

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