Abstract: The present invention relates to a prefunctionalized metallic nanoparticle (10) as a standardized basic building block of biofunctionalized nanoparticles (40), having a thiol-reactive metallic nanoparticle (12) that is prefunctionalized by a bifunctional molecule (20) that consists of an anchor component (22) and a short further-functionalization stub (24). Here, it is provided that the anchor component (22) comprises one or more dithiophosphate groups, and the short further-functionalization stub (24) is adapted for the attachment of a desired biofunctionalization (30) and is selected from the group consisting of i) an unmodified standardized oligonucleotide strand (26) having 2 to 18 bases for further-functionalization with biomolecules (30) having a terminal complementary strand (36) of the standardized oligonucleotide strand (26), and ii) a 2- to 18-base-long oligonucleotide strand (50; 60) that is modified with a terminal reactive group (52; 62) for biomolecules.