PEGylation of Human growth hormone with Methoxy PEG Succinimidyl Carbonate and study of its half-life and stability

Human growth hormone (hGH) use is increasing due to its important biological functions and therapeutic applications, the use of growth hormone for the treatment of obesity, short stature, burns and the importance of this hormone for athletes. Nowadays, the short half-life of hGH is a major challenge associated with the usage of this drug in the world. PEGylation is an effective approach to increase half-life and stability of biopharmaceutical proteins. Polyethylene glycol (PEG) due to high aqueous solubility is considered as a versatile candidate for pharmaceutical protein conjugation. Accordingly, in this study the PEGylation of human growth hormone and its plasma half-life and stability were carried out.
hGH was PEGylated by using Methoxy PEG Succinimidyl Carbonate (mPEG-SC) at 8 °C for overnight. In this study, SDS-PAGE, Dynamic Light Scattering (DLS), and ELISA techniques were used to prove PEGylation reaction.
The SDS-PAGE results showed high yield PEGylation of hGH under aqueous conditions. The zeta-potential, as an indicator of the Surface charge of PEGylated hGH, was analyzed by DLS technique. The ELISA results shown the increase half-life of pegylated hGH to 12 times.
In the present study, we demonstrated that the PEGylation of lysine and/or histidine residues significantly increased the half-life of the human growth hormone.