PEG-g-PEI is a graft copolymer of branched PEI, which is modified with multiple PEGs of indicated MW. The PEG to PEI grafting (g) ratio is the average number of PEGs per PEI. For 25,000 MW PEI, PEG/PEI ratio of 30 is roughly 5% of PEI units grafted with PEGs. Custom service is available for any MW of PEI and any MW of PEG at any graft ratio PEG-g(x)-PEI.
PEG-PEI is a copolymer of cationic poly(ethylene imine) (PEI) and polyethylene glycol (PEG). They markedly improve the in vitro and in vivo delivery of oligonucleotides and nucleic acids (DNA, siRNA). By varying the MW of PEI and PEG, PEG-PEI drug conjugates, polyplexes or nanoparticles can be prepared with a dynamic range of size, surface charge, and stability, which all are important to the transfection efficiency. PEG-PEI copolymers can be synthesized with customer specified MW.