Amine-reactive phosphine reagents for azide-phosphine chemoselective ligation.
Thermo Scientific NHS-Phosphine and Sulfo-NHS-Phosphine are amine-reactive compounds that can be used to derivatize primary amines of proteins or amine-coated polymer surfaces for ligation to azide-tagged molecules.
These NHS-ester compounds react to form covalent bonds with primary amines (e.g., side chain of lysine residues or aminosilane-coated surfaces). The phosphine groups (PPh2) react with azide-labeled molecules by a mechanism known as Staudinger chemistry, enabling efficient and specific conjugation of derivatized molecules in biological samples. In combination with different azide-tagged compounds, these NHS-Phosphine reagents facilitate a variety of labeling and crosslinking experimental strategies for investigating protein interactions and cellular pathways.
Soluble – reagents easily dissolve in water-miscible solvents for subsequent dilution in aqueous reaction mixtures with cell lysates and other biological samples (Sulfo-NHS-Phosphine is directly water-soluble)
Compatible – reaction chemistry occurs effectively in simple buffer conditions; requires no accessory reagents such as copper or reducing agents
Specific – NHS esters are specific for covalent attachment to primary amines (side chain of lysine or N-terminus of polypeptides)
Chemoselective – Azide and phosphine groups do not react or interfere with components of biological samples but conjugate to one another with high efficiency
Chemical structures of NHS-activated (amine-reactive) phosphine ligation reagents. These reagents label proteins and molecules that contain primary amines (e.g., side-chain of lysine) via the NHS Ester Reaction Chemistry. Labeled molecules will contain a phosphine group (P3), which can be conjugated azide-activated molecules via the Staudinger Ligation Reaction Chemistry.
Properties of NHS-Phosphine reagents. These compounds produce the same conjugation product because the group that differs (NHS vs. Sulfo-NHS) is a leaving group in the reaction.