Abstract: A complex including: a support provided with at least two faces one of which is provided with a coating of an adhesive, at least one ligand, said ligand being immobilized on the adhesive surface. The ligand implemented within the framework of the present invention is chosen from among proteins, peptides, antibodies, nucleic acids, sugars or oligosaccharides, toxins, pesticides, hormones, herbicides, fungicides, neurotransmitters.

Abstract: The invention relates to the use of nanoparticles with dimensions comprised between 1 and 50 nm, at least one portion of which consists of at least one oxide and/or one oxohydroxide of at least one lanthanide, said nanoparticles: either consisting of at least one oxide and/or one oxohydroxide of at least one lanthanide, or in the form of nanoparticles comprising a core consisting of at least one oxide and/or one oxohydroxide of at least one lanthanide, and a coating consisting of polysiloxane, with possibly organic molecules grafted at the surface or comprised inside it, as a radio-sensitizing agent in the making of an injectable composition intended to improve the efficiency of the treatment of a tumor by X or gamma irradiations.