The photoluminescence properties of silicon nanoparticles ''Si NPs'' have their application as fluorophore in the field of biology . Their use as probes in lubricated contacts is very promising because of their resistance to mechanical stresses and harsh environment. A top-down technology, electrochemical anodization, is used for the development of these NPS. Their size selection is obtained by centrifugation. The surface functionalization of these NPs is an essential step for their dispersion in non-polar liquids. The main results of photoluminescence as a function of temperature are presented.