Bimetallic Au-Ru nanoparticles (NPs) with novel core-shell morphology were prepared through a single-step microemulsion synthesis for the decoration of COOH surface modified multi-walled carbon nanotubes (fMWCNTs). The presence of Ru leads to particles with smaller diameters, improved distribution and adhesion on fMWCNTs, affording very good accessibility to the catalytic sites. Thereby, Ru exists in a highly amorphous state in the shell and as a solid solution in the gold lattice of the core. The effect of Ru on the activity and effectiveness of the catalyst were studied in alkaline solutions. Au-RuNPs/fMWCNTs exhibits a high sensitivity of 28.7 mu A mM(-1) cm(-2) toward glucose and provides a linear range for physiological concentrations (1 mM-10 mM). Contrary to Au the Au-RuNPs/fMWCNTs electrode is highly resistant against poisoning by chloride ions, and the interference from the oxidation of common interfering species is effectively suppressed. Additionally, the presence of other sugars affects only marginally the response toward glucose. The role of Ru and the special core-shell morphology are discussed. The Au-RuNPs/fMWCNTs electrode exhibits good selectivity, high sensitivity toward glucose oxidation and applicability for glucose detection in real human serum samples, thus is promising for the future development of non-enzymatic glucose sensors. (c) 2017 The Electrochemical Society.