Fmoc-Lys (biotin-PEG4)-OH is a Lysine embedded biotin PEG linker containing a carboxylic group and Fmoc-protected amine. The carboxylic acid readily reacts with primary and secondary amino group and forms stable amide bonds. The Fmoc group can be deprotected under basic condition to form a fee amine, which can be used for further conjugations. The hydrophilic PEG spacer improves the water solubility of the resulting biotinylated molecule.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.