Crosslinking, modifying, and labeling proteins are commonly used techniques for studying the structure and interaction of proteins. Crosslinking is the process of chemically joining two or more molecules by a covalent bond. Modification involves attaching or cleaving chemical groups to alter the solubility or other properties of the original molecule. Labeling generally refers to any form of crosslinking or modification whose purpose is to attach a chemical group (e.g., a fluorescent molecule) to aid in detection.

Popular protein labeling & crosslinking products

Sulfo-NHS-LC Biotin Kits



Featured protein labeling & crosslinking categories

Labeling reagents and kits, including biotinylation, iodination, and metabolic labeling reagents and enzyme-protein conjugations for detecting proteins in tissues, cells, or biochemical assays

Activated fluorescent dyes and kits for labeling antibody or protein functional groups with FITC, fluorescein, rhodamine, or Alexa Fluor® and DyLight™ dyes to create molecular probes for fluorescence imaging

Reagents to modify proteins by attaching various prosthetic groups to allow manipulation and study of protein function and interactions

Reagents to modify proteins by crosslinking to study of protein function and interactions

Biotinylation reagents and kits to chemically tag and label antibodies, proteins, and peptides with biotin at particular amino acid functional groups to create labeled antibody or other probes for streptavidin affinity binding, purification, and detection

Activated linear and branched derivatives of polyethylene glycol (PEG) for PEGylation and PEG-modification of peptides and proteins via primary amines and sulfhydryl groups to increase solubility, prolong stability, and reduce immunogenicity


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Protein quantitation immunoassays