Organometallic labels for the detection of biomolecules, methods of synthesis and processes for conjugating an organometallic labels to a biomolecule

A labeling molecule comprising:

• i. an identification moiety;
• and
• ii. a coordination agent moiety;
• wherein
• the coordination agent moiety comprises free amino (—NH2) and free carboxylate (—COO−) groups which bind to a residue on a surface of a targeted biomolecule through noncovalent or covalent interactions.

A method of labeling a target biomolecule comprising:

• providing a labeling molecule comprising (i) a label anchor moiety;
• (ii) an identification moiety;
• and (iii) a coordination agent moiety;
• and
• contacting one or more surface residues of a target biomolecule to one or more labeling molecules in a single step, in an aqueous environment,
• wherein the one or more labeling molecules comprise the same transition metal coordinated to the coordination agent moiety or a different transition metal coordinated to the coordination agent moiety.

A method for identifying a single biomolecule or a plurality of biomolecules comprising:

• a. providing a plurality of different labels comprising one or more of:
• i. a label anchor moiety;
• ii. an identification moiety, wherein the identification moiety of each of the plurality of labels is a different metal;
• or
• iii. a coordination moiety;
• wherein the label anchor comprises a functional moiety or a functionalized linker for coupling to a surface residue of a biomolecule;
• and
• b. detecting the plurality of labeled biomolecules by elemental spectroscopy using a transmission electron microscope, elemental spectroscopy using a scanning electron microscope, or by measuring the molecular weight of the labeled biomolecule using a mass spectrometer.