Biotinylation is the process of covalently attaching biotin to a protein, nucleic acid or other molecule. Biotin-binding to streptavidin and avidin is resistant to extremes of heat, pH and proteolysis, making capture of biotinylated molecules possible in a wide variety of environments. Also, multiple biotin molecules can be conjugated to a protein of interest, which allows binding of multiple streptavidin, avidin or Neutravidin protein molecules and increases the sensitivity of detection of the protein of interest.