Polyethylene glycol and its derivatives are polyether compounds with many applications, from industrial manufacturing to medicine. Researches on PEG and its derivatives become a hot topic in decades, especially in the medical and biological fields. PEG and its derivatives bring new hope for difficult miscellaneous diseases. In the past years, gene therapy and 'biological' medicines bring a healthier and more effective therapy, the core of those developments mostly come from Polyethylene glycol and its derivatives.
Biologics as therapeutics have gained substantial relevance during the past decades. Many of them are growth factors, interferon, enzymes, or antibodies and essentially contribute to the successful treatment of severe human diseases today. However, biologics routinely suffer from premature degradation by the patient defense system or renal excretion. The most established and best-validated drug delivery strategy to overcome these problems is “PEGylation”, the modification of molecules with polyethylene glycol (PEG). Prominent examples are PEG-Intron®, Cimza®, Pegasys®, Adynovate®, Plegridy® being blockbuster products in the market.
Till now chemists from all over the world continue to explore widely and effective use on PEGs, and now PEGs and PEGylation technical is used as a crowding agent in vitro assays to mimic highly crowded cellular conditions; used as a precipitant for plasmid DNA isolation and protein crystallization; used as a potentiator to enhance detection of antigens and antibodies, etc.
As one of the most potential topic in pharmacy and bioresearch, PEGs also has its limitation. Unpredictability in clearance times for PEGylated compounds may lead to the accumulation of large molecular weight compounds in the liver leading to inclusion bodies with unknown toxicologic consequences. With the deepening of research, the limitations of polyethylene glycol will be gradually overcome, the scope of application will become wider and wider, and more high-quality PEGylation pharmaceutical products will be developed and applied.