Combinatorial Discovery of Alloy Electrocatalysts for Amperometric Glucose Sensors

Abstract

Combinatorial methods were used to search for active alloy electrocatalysts for use in enzyme-free amperometric glucose sensors. Electrode arrays (715-member) containing combinations of Pt, Pb, Au, Pd, and Rh were prepared and screened by converting anodic current to visible fluorescence. The most active compositions contained both Pt and Pb. Bulk quantities of catalysts with compositions corresponding to those identified in the screening experiments were prepared and characterized. The best alloy electrocatalysts catalyzed glucose oxidation at substantially more negative potentials than pure platinum in enzyme-free voltammetric measurements. They were also insensitive to potential interfering agents (ascorbic and uric acids, and 4-acetamidophenol), which are oxidized at slightly more positive potentials. Rotating disk electrode (RDE) experiments were carried out to study the catalytic mechanism. The improvement in catalytic performance was attributed to the inhibition of adsorption of oxidation products, which poison Pt electrodes.

Performances of Enzymatic Glucose/O2 Biofuel Cells

“…Oxidation of glucose on metallic surfaces has extensively been studied. Among all these investigations, numerous ones have been devoted to the understanding of catalytic effect of platinum on glucose oxidation process (Kokoh et al, 1992a;Kokoh et al, 1992b;Sun et al, 2001). Experiments led to conclude that the major oxidation product is gluconic acid (Kokoh et al, 1992b;Rao & Drake, 1969).…”

“…To solve this problem, different heavy atoms (Tl, Pb, Bi and W) have been used as adatoms to modify platinum surfaces to raise electrochemical activity of platinum (Park et al, 2006). Other studies relate glucose oxidation on platinum alloys in which the second metal can be Rh, Pd, Au, Pb (Sun et al, 2001), Bi, Ru and Sn (Becerik & Kadirgan, 2001). It appears that the most efficient catalysts are Pt-Pb or Pt-Bi (Becerik & Kadirgan, 2001).…”

“…The oxidation of glucose on gold-platinum nanoparticles has been investigated in numerous studies (Habrioux et al, 2007;Sun et al, 2001). Jin and Chen (Jin & Chen, 2007) examined glucose oxidation catalyzed by Pt-Au prepared by a co-reduction of metallic salts.…”

Fabrication of biosensors using vinyl polymer-grafted carbon nanotubes

“…PtAu (Habrioux et al, 2007;H. Liu et al, 1992), Pt-Pb (Cui et al, 2007;Bai et al, 2008;Sun et al, 2001), and Pt-Ru (Xiao et al, 2009) have all displayed high electrocatalytic activity for glucose oxidation. Effective fabrication of electrocatalysts also depends on the support material (Hsu et al, 2008).…”

Fluorescent Si nanoparticle-based electrode for sensing biomedical substances

“…This sensing approach is adopted to replace enzyme-based sensors due to enzymes' intrin sic instability under physiological conditions. To date, enzyme-free sensors have been made using noble metals [1.2], all oys of these metals (3], conducting polymers [4] and carbon nanotubes [5]. These sensors, whi le rendering device stability, sti ll suffer from issues related to material selectivi ty and/or electrode poison ing due to adsorption of reaction intermediates.…”