Amperometric nonenzymatic sensing of glucose at very low working potential by using a nanoporous PdAuNi ternary alloy

The authors present a nonenzymatic sensor for glucose that has an exceedingly low working potential which makes the sensor highly selective over other electroactive species. The sensor is based on the use of a glassy carbon electrode (GCE) that was modified with a nanoporous PdAuNi alloy (np-PdAuNi). The PdAuNi alloy nanostructure displays enhanced electrocatalytic activity for glucose oxidation (compared to PdNi alloys). The modified GCE enables amperometric sensing of glucose at a typical working electrode potential of 0.0 V vs. SCE in solutions of pH 13 containing 0.1 M NaCl. Response is linear in the 5 to 100 mu M concentration range, with a 1.7 mu M detection limit (at an S/N ratio of 3). For higher concentrations deviations from linearity were found. The method is selective and reproducible. The modified electrode was applied to the determination of glucose in human serum.