A wide variety of labels and conjugation techniques are known and reported extensively in both the scientific and patent literature. Preferred detectable labels include, but are not limited to, a fluorescent label, a radioactive label, a paramagnetic particle, a chemoluminescent label (Bohmer, US 2005/0287604).
Antibody Labeling:
Bohmer (US 2005/0287604) teaches using a composition comprising IgM binding compounds such as a secondary antibody which are bound to a detectable label such as a radioactive label, capable of providing a detectable signal ( ¶9, 15, 74, 84 and 106).
Fluorescent Techniques
Ph Sensitive Dyes
–CypHer5E: is minimally fluorescent at basic pH and maximally fluorescent at an acidic pH and thus ideally suited to report the movement of a receptor form the cell surface into internal acidic endosomes. This dye has been used for receptor internalization assays because itis ideally suited to report movement of a receptor from the cell surface into internal acidic endosomes. It is compatible with IN Cell Analyzer 3000, In Cell Analyzer 1000 and other cell imaging systems. (GE Healthcare 258010-12UM).
Radioactive Labeling
–Chelating Agents for Radioactive Labeling:
Schibli (WO 2004/106939A2) teaches chemical modification of proteins with a bifunctional chelating agent for stable in vivo coordination of radionuclides (p.1, lines 28-30) which provides site-specific labeling (p2, line 9). Schibli teaches that “radioactively labeled monoclonal antibodies (mAb), antibody fragments (scFV) and peptides are very important molecules for diagnosis and therapyof cancer. But also other proteins can be radioactively labeled and applied in diagnosis and therapy or otherwise” (p. 1, lines 15-19).