Labeling Chemistry

Fluorescent labeling of biomolecules enables researchers to detect specific components of complex biological assemblies with exquisite sensitivity in applications ranging from imaging and flow cytometry, to western blots. We offer a full spectrum of Invitrogen labeling chemistries for labeling antibodies, proteins, peptides, ligands, synthetic oligonucleotides and other biomolecules for use with immunochemistry, fluorescence in situ hybridization (FISH), cell tracing, receptor labeling, and cytochemistry applications as well as probing biological structure, function and interactions. Also available are tools for conjugation of biotin and other haptens to biomolecules.

Find your labeling product

Labeling amines

Amine-reactive dyes are widely used to modify proteins, peptides, ligands, synthetic oligonucleotides and other biomolecules. They are most often used to prepare bioconjugates for immunochemistry, fluorescence in situ hybridization (FISH), cell tracing, receptor labeling and cytochemistry.

Learn more about Fluorophores and Their Amine-Reactive Derivatives - Chapter 1


Labeling thiols

Efficiently prepare fluorescent proteins, peptides, and sulfhydryl-modified oligos for analyzing protein structure and function.

Learn more about Thiol Reactive Probes - Chapter 2


Click chemistries

Click-iT products employ click chemistry—a powerful method for joining biomolecules quickly and specifically.

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  • Click-iT Assay Kits (including kits for protein analysis, cell proliferation, TUNEL assays for apoptosis, RNA synthesis, lipid peroxidation, and for nascent protein and RNA capture)
  • Click-iT Labeling and Detection Tools (including products for nascent proteins, nascent DNA, and nascent RNA; farnesylated, geranylgeranylated, fucosylated, palmitylated, and myristoylated proteins; O-linked gylcoproteins and sialic acid-modified glycoproteins; and choices for labeling using copper-free reactions)

Labeling carboxylic acids, aldehydes & ketones

Efficiently label aldehydes and ketones in low molecular weight structures such as drugs, steroid hormones, reducing sugars, and metabolic intermediates.

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Bifunctional crosslinking

Bifunctional cross-linking reagents to covalently link two target groups, including amine–amine, amine–thiol, and amine–carboxylic acid.

Learn more about Crosslinking and Photoactivatable Reagents - Chapter 5


  • Crosslinkers (including heterobifunctional, homobifunctional, and photoactivatable crosslinkers)

Labeling proteins, peptides & antibodies

A comprehensive selection of innovative and time-tested antibody and protein labeling kits including our monoclonal antibody labeling kits, Invitrogen APEX antibody labeling kits and our classic protein labeling kits.

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Labeling nucleic acids

Directly label DNA, RNA, and oligonucleotides with intensely fluorescent dyes.

Learn more about Labeling Oligonucleotides and Nucleic Acids - Section 8.2



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