Merck Chemicals

more less

Drug Delivery


Both polyethylene glycol (PEG) and monomethoxy polyethylene glycol (MPEG) have been used for many years as non toxic auxiliary materials in cosmetics, foodstuffs and pharmaceuticals and are approved by the FDA.
The conjugation of PEGs or MPEGs to therapeutic proteins improves their in vivo circulating half-life and the solubility of proteins in aqueous solution.
The PEG chain modulates the pharmacokinetic and -dynamic profile in a way that the amount of administered active pharmaceutical ingredient can be reduced without compromising the drug’s efficacy.
PEGylated therapeutic proteins have a reduced toxicity and are almost non immunogenic. As a result, therapeutic side effects are significantly reduced as compared to the unmodified protein.



Size comparison of PEG with other molecules

When attached to an API, polyethylene glycole (PEG) allows for a decelerated clearance of the drug. This induces longer-acting medicinal effects, reduces toxicity and allows for longer dosing intervals. Examples include PEG-interferon alpha (hepatitis C) and PEGfilgrastim (neutropenia).




© Merck KGaA, Darmstadt, Germany, 2014


Welcome to Merck Millipore


Europe, Middle East and Africa Asia / Pacific North America, Central America and the Caribbean South America

Please choose your country:

North America, Central America and the Caribbean

South America

Europe, Middle East and Africa

Asia / Pacific

All countries from A to Z

If you can't find your country please click here.


Privacy Statement



Merck Chemicals Cart ()

You are entering the Millipore online shop. Both carts are maintained for you while you shop between sites. We recommend to complete your Merck order before visiting

Go to Millipore Proceed to checkout

What kind of products are you looking for?


Bio manufacturing and Life science.

Merck Chemicals

High-quality industrial and laboratory chemicals.

Important message

It is currently not possible to order Bioscience products together with other Merck products. We recommend completing your current order first.

Do you wish to proceed without completing your current order? If so, this will empty your shopping cart.