This product is a kit for preparing immunoliposomes conjugated to ligands, proteins or peptides through the formation of stable amide bonds between activated NHS and their amine groups. It consists of one tube of pre-formed liposome, one tube of reactive PEGylated lipid (DSPE-PEG2000-NHS) and one tube of non-reactive PEGylated lipid (DSPE-PEG2000).