The application of ferrocene-containing dendrimers as mediators in amperometric biosensors is described. The steady-state amperometric response of carbon paste electrodes containing these dendritic relay systems and glucose oxidase is investigated as a function of the glucose concentration and the applied potential. The results show that these sensors respond rapidly to the addition of glucose. The dependence of the glucose sensor response on the size, the number of organometallic redox centers and the nature of the organosilicon dendritic framework is discussed.