General description
Iodoacetyl-LC-Biotin is a haloacetyl-biotin compound used for labeling sulfhydryl group bearing protein cysteines and other molecules. It is a mid-length, haloacetyl-activated, sulfhydryl-reactive biotinylation reagent that forms stable, irreversible thioether bonds at an alkaline pH. This reagent specifically reacts with reduced thiols (-SH) in alkaline buffers to form irreversible thioether bonds. The unique feature of Iodoacetyl-LC-Biotin is its extended but chemically simple hexylenediamine spacer arm. Biotinylation reagents differ in their reactivity, length, solubility, cell permeability and cleavability. Iodoacetyl reagents specifically react with sulfhydryl groups (-SH) at pH 8.3 to form irreversible thioether bonds. In proteins, sulfhydryls exist where there are cysteine (C) residues. Cystine disulfide bonds must be reduced to generate sulfhydryl groups available for labeling. Hinge-region disulfide bridges of antibodies can be selectively reduced to make functional half-antibodies that can be labeled.
Synonyms:  N-Iodoacetyl-N-biotinylhexylenediamine, Long-chain (LC) iodoacetyl-biotin N-Iodoacetyl-Nbiotinylhexylenediamine–Hexahydro-N-[6-[2-iodoacetyl)amino]hexyl]-2-oxo-1Hthieno[3,4-d]imidazole-4pentanamide
CAS No.:Â Â Â Â 93285-75-7
Applications:
• Electron microscopy studies on spatial relationships between proteins
• Localizing the SH1 thiol of the myosin head using avidin-biotin complexes in electron microscopy
Features of EZ-Link Iodoacetyl-LC-Biotin:
- Protein labeling—biotinylate antibodies or other proteins
- Membrane-permeable—can be used for intracellular labeling
- Thiol-reactive—reacts with sulfhydryls (-SH)
- Iodoacetyl-activated—reacts in the dark at pH 7.5 to 8.5 in Tris/borate buffer
- Irreversible—forms permanent thioether bonds; spacer arm non-cleavable
- Solubility—must be dissolved in DMSO/DMF before dilution in aqueous buffers
- Medium length—spacer arm is 27.1 Å; contains hexylenediamine extension
