PEI-PEG-PEI is a block copolymer of two linear PEI (LPEI) with one linear PEG, LPEI-PEG-LPEI. The MW indicated in the product refers to the MW of each PEI block. PEI is capped with hydroxyl group.
PEG-PEI, copolymers of cationic poly(ethylene imine) (PEI) and polyethylene glycol (PEG) are well-studied compounds that 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.