Pegylation – in search of balance and enhanced bioavailability

In the process of finding better therapeutics, thousands new molecules are synthesised every day. Many these can be poorly soluble in water, leading to a potentially promising drug being rejected during testing due its poor solubility. Polyethylene glycol (PEG) has become known as an excellent modification remedy this and was initially used increase circulation time reduce immunogenicity therapeutic proteins. Thus significantly increasing their safety range use. Another group compounds which significant benefits pegylation have been seen photosensitisers. Used photodynamic therapy, they often characterised by very high hydrophobicity. Pegylation structure increases affinity for cancer cells facilitates penetration through cell membranes. Classical small-molecule drugs benefit from temporary combinations hydrolysed body or short PEG chains. This approach allows bioavailability while avoiding disadvantages small molecule pegylation. However, most common motive recently is creation carriers. Liposomes nanoparticles make it possible exploit advantages stabilise not modifying active compound. Unfortunately, PEGs also drawbacks. The first molecular weight range, especially longer chains, poses difficulties purification. emergence antibodies directed against PEG. Nevertheless, still up-and-coming method pharmaceutically molecules.