m-PEG-DMG (MW 2000) is a PEG lipid for the preparation of liposomes and can be used in drug delivery studies[1].
References
[1] Gill, et al. "PEG–lipid micelles as drug carriers: physiochemical attributes, formulation principles and biological implication." Journal of drug targeting 23.3 (2015): 222-231. DOI:10.3109/1061186X.2014.997735