In the field of fluorescent semiconductor quantum dots (QDs), alloyed QDs open up new possibilities and opportunities. Indeed, these systems allow to tune the optical properties of the nanocrystals without changing their size. This is of particular interest for the integration of the QDs in devices such as LEDs or for their use as biological labels. We recently developed a novel method for the synthesis of CdSe and ZnSe binary QDs in colloidal solutions that is fast and highly efficient. This method is based on a heterogeneous Se-ODE precursor consisting of a simple dispersion of Se powder (200 mesh) in octadecene (ODE) and showing very high reactivity towards Cd precursor. In this contribution we will demonstrate that this method can be extended to the synthesis of CdSe1-xSx homogeneously alloyed QDs (0 ≤ x ≤ 1)