PEG PFP ester linkers are a type of PEG labeling reagent that reacts with primary and secondary amines. Compared with NHS esters, pentafluorophenyl (PFP) esters are less prone to hydrolysis and therefore have higher reaction efficiency. It can be used for homobifunctional or heterobifunctional labeling, such as surface modification of nanoparticles and cells.
PEG phosphonic acid and its ester provides an ideal tool for nano particle surface modification.