Biodegradation polyethylene glycol

Minamitake, Y., Gref, R., Hrkach, J., Peracchia, M. T., Domb, A., and Langer, R., 1994, Injectable nanospheres made of biodegradable polyethylene glycol-poly(lactic-co-glycolic) acid diblock copolymers. Paper in preparation. 

Schramm E, B Schink (1991) Ether-cleaving enzyme and diol dehydratase involved in anaerobic polyethylene glycol degradation by a new Acetobacterium sp. Biodegradation 2 71-79. 

Wang, P., Woodward, C.A., and Kaufman, E.N., Polyethylene glycol)-modified ligninase enhances pentachlorophenol biodegradation in water-solvent mixtures, Biotechnol. Bioeng., 64, 290-297, 1999. 

Fig. 8 Nanosystems that may function as simultaneous drug delivery and imaging agents for targeting T cells (a) liposomal systems, (b) solid biodegradable nanoparticulates, and (c) macro-molecular dendrimer complexes. PEG polyethylene glycol, Gd-DTPA gadolininum-diethylene triamine penta acetic acid. (Adapted from [48])...

The only study available on metabolites of AE was performed by Crescenzi et al. [17]. The initial biodegradation of AE occurs by cleavage at the ether bridge between the alkyl and ethoxylate chain, resulting in polyethylene glycols (PEG) and alcohols. In consecutive oxidation steps, the PEG chains are shortened and mono- and dicarboxylated metabolites (MCPEG and DCPEG, respectively) are formed. 

Although the release of tobramycin sulphate can be significantly improved with the addition of water-soluble additives such as polyethylene glycol 400, our current investigations are directed toward the design and development of biodegradable implants. 

Observations Cell-occlusive polyethylene glycol containing biodegradable barrier... 

Because of the resemblance to the 1,4-butane diol in the above example, it is worth mentioning that polyethylene glycol) (PEG) and poly(propyleneglycol) (PPG) have attracted interest as novel solvents for catalytic processes (see Fig. 7.2 for examples). They are both relatively inexpensive and readily available materials. They are essentially non-toxic (PPG is often used as a solvent for pharmaceutical and cosmetic preparations and both are approved for use in beverages) and have good biodegradability. Moreover, they are immiscible with water, non-volatile, thermally robust and can, in principle, be readily recycled after removal of the product. 

Yeh, M. K. (2000), The stability of insulin in biodegradable microparticles based on blends of lactide polymers and polyethylene glycol,/. Microencapsul., 17, 743-756. 

Wang used reactive-extrusion polymerization with 2,5-di-methyl-2,5-di-t-bu-tylperoxy hexane to prepared a graft copolymer, (11), by free radically grafting polyethylene-glycol malonic acid onto the biodegradable substrate of poly((3-hydroxybutyrate-co- p-hydroxy valerate). 

Polyethylene glycols (PEGs) are widely used in a variety of pharmaceutical formulations including parenteral, topical, ophthalmic, oral, and rectal preparations. It has been used experimentally in biodegradable polymeric matrices used in controlled-release systems. 

Like other polymeric substances, polyethylene glycols are not readily biodegradable. However, owing to their hydrophilicity, they have a low potential to bioaccumulate. 

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