In this communication, we report a review of our works on luminescent and magnetic bifunctional structures in the nanoscale range. The synthesis and characterisation of various colloidal nanostructures such as Y<sub align="right">3</sub>Fe<sub align="right">5-x</sub>Al<sub align="right">x</sub>O<sub align="right">12</sub>-TRITC, γ-Fe<sub align="right">2</sub>O<sub align="right">3</sub>-Cs<sub align="right">2</sub>Mo<sub align="right">6</sub>Br<sub align="right">14</sub>@SiO<sub align="right">2</sub> and γ-Fe<sub align="right">2</sub>O<sub align="right">3</sub>-QDs will be presented. At the outset, the first synthesis of aluminium substituted garnet Y<sub align="right">3</sub>Fe<sub align="right">5-x</sub>Al<sub align="right">x</sub>O<sub align="right">12</sub> by the citrate gel process and its surface modification by TRITC through grafting of 3-aminopropyltrimethoxysilane (g-APS) for hyperthermia application will be reported. Secondly, the synthesis of nanoparticles under restricted environments offered by water-in-oil microemulsions provides excellent control over particle size and shape and interparticle spacing. These environments have been used in the synthesis of silica nanoparticles (50 nm) with a magnetic nanocrystalline core surrounded by optically active molybdenum atoms clusters. Finally, we will resume the preparation of composite magnetic-QD bioconjugable micelles by simultaneous encapsulation of hydrophobic CdSe/ZnS QDs (2-4 nm) and magnetic γ-Fe<sub align="right">2</sub>O<sub align="right">3</sub> nanoparticles (3-4 nm) into water soluble micelles of synthetic functional PEG amphiphiles bearing a bioactivable terminal group.< Réduire