I am slightly confused, it seem's as some of the threads throw MGF and Peg-Mgf around loosely and it can sometimes be interpreted as the same thing (at least to myself). I just wanted to be clear on some of the information on which is which.
Here's a good explanation I found: Base MGF which is produced in liver and secreted into the blood stream, only lasts for about 5-7 minutes before it breaks down. This is the regular “base” MGF version that’s not widely used due to the short half-life. Just as IGF-1 was modified to be IGF-1LR3 (the longer acting version), the same has been done with MGF. The additive polyethylene glycol was added to the MGF chain in order to give it a half life of several days.