Abstract

Protein administration is often associated with practical problems due to it biological degradation in a very short time. Pegylation modification with monopolyethylene glycol (mPEG) is one of the ways to enhance thermal stability and solubility in organic solvents. mPEG can be applied to the development of diagnostics, targeting or imaging agents, and can be used in kinetic analysis or receptor binding studies. The mechanism of the immune system can also be deduced using these modified compounds. Pegylation can also be applied to other system like liposomes to enhance effectiveness of the delivery system. Site directed attachment and noncovalent attachment of mPEG open up the entire new spectrum of possibilities. Molecular weight changes and charge of the mPEG attached also provide new possibilities, thus opportunities for producing longer acting and cost effective end products. Realization of new thrilling horizon in the field of drug delivery system with polyethylene glycol is in the offing.