The use of gold catalysts in the oxidation of glucose resulted in high selectivities (> 95%) with respect to gluconic acid and very high catalytic activities were obtained. A catalyst with 0.45 wt.% Au supported on titania showed the best performance. The optimisation of the reaction conditions revealed that best results were obtained at a reaction temperature in a range of 40-60 degrees C and a pH value of 9. The Au/TiO2 catalyst can be re-used at least 17 times without loss of activity or change of the gold particle size. (c) 2006 Published by Elsevier B.V.