Voltammetric analysis of europium at screen-printed electrodes modified with salicylamide self-assembled on mesoporous silica

Wassana Yantasee, Glen E. Fryxell, Yuehe Lin

Research output: Contribution to journalArticle

20 Scopus citations


Mercury-free sensors for europium (Eu3+) assay based on the chemical modification of screen-printed carbon electrodes (SPCEs) with self-assembled salicylamide on mesoporous silica (Sal-SAMMS) have been developed. The preconcentration of Eu3+ at SAMMS-based sensors utilizes the binding affinity of the salicylamide and Eu3+, accomplished at open circuit potential without electrolyte and solution de-gassing. Optimal Eu detection was obtained after 3-5 min preconcentration in Eu solution (pH 2-6), electrolysis at -0.9 V for 60 s in a new medium (0.1-0.2 M NH4Cl, pH 3.5), followed by a square-wave voltammetric detection of Eu in the same electrolyte. Attributed to the strong covalent bonding of the functional groups on mesoporous silica and silane cross-linking, the SAMMS-modified SPCEs with a built-in 3-electrode system can be re-used for tens of measurements with minimal degradation, enabling the establishment of the calibration curve and lowering the costs. A linear calibration curve was found in the range of 75 to at least 500 ppb Eu3+ after 5 min preconcentration. The experimental detection limit was 10 ppb after 10 min preconcentration, which can be improved with increased preconcentration time. Reproducibility (% RSD) of 100 ppb Eu2+ was 10% for a single sensor and 10% for 5 sensors, which can be improved through the precision of sensor manufacturing, in which SAMMS modification can be made in-situ.

Original languageEnglish (US)
Pages (from-to)1342-1346
Number of pages5
Issue number12
StatePublished - Nov 29 2006


ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Environmental Chemistry
  • Spectroscopy
  • Electrochemistry

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