Ligand building blocks can carry a variety of functionalities, including fluorescent labels, affinity tags and attachments to a solid phase. The covalent bond forms rapidly under general physiological conditions, is highly specific and essentially irreversible. The HaloTag® Ligand Building Blocks allow researchers to apply the chloroalkane group that HaloTag® protein reacts with to any compound or surface with a compatible chemical group, creating endless possible applications.

• Image live or fixed mammalian cells expressing HaloTag® protein or protein fusions
• Analyse post-translational modification
• Isolate proteins and protein complexes

HaloTag® Amine (O₂) ligand: Contains a reactive amine group connected to an alkylchloride, separated by an ethylene glycol repeat (O₂). It can be successfully conjugated to any reporter group, protein, or nucleic acid derivative containing an activated carboxylic acid, sulphonyl halide or isocyanate.

HaloTag® Amine (O₄) ligand: Contains a reactive amine group connected to an alkyl chloride, separated by an ethylene glycol repeat (O₄). It can be successfully conjugated to any reporter group, protein, or nucleic acid derivative containing an activated carboxylic acid, sulphonyl halide or isocyanate.

HaloTag® Iodoacetamide (O₂) ligand: Contains a reactive iodoacetamide group connected to an alkylchloride separated by an ethylene glycol repeat (O₂). HaloTag® Iodoacetamide (O₂) Ligand has been designed to rapidly react with sulfhydryl-containing molecules (see figure), whether small organic compounds, peptides or proteins. The ligand with functional group can then be used with the HaloTag® protein for any application of interest.

HaloTag® Iodoacetamide (O₄) Ligand: Contains a reactive iodoacetamide group connected an alkyl chloride separated by an ethylene glycol repeat (O₄). It has been designed to rapidly react with sulfhydryl-containing molecules, whether small organic compounds, peptides or proteins. The ligand with functional group can then be used with the HaloTag® protein for any application of interest.

HaloTag® Succinimidyl ester (O₂) ligand: Contains a reactive succinimidyl ester (SE) group connected to an alkylchloride separated by an ethylene glycol repeat (O₂). It can be successfully conjugated to any reporter group, protein, or nucleic acid derivative containing an amine, forming stable amide bond linkages. The ligand with functional group can then be used with the HaloTag® protein for any application of interest.

HaloTag® Succinimidyl ester (O₄) ligand: Contains a reactive succinimidyl ester (SE) group connected to an alkyl chloride separated by three ethylene glycol repeats (O₄). It can be successfully conjugated to any reporter group, protein, or nucleic acid derivative containing an amine, forming stable amide bond linkages. The ligand with functional group can then be used with the HaloTag® protein for any application of interest.