Yun, Q.Yang, R.Chen, T.Bi, J.Ma, G.Su, Z.2008-07-142008-07-142005Journal of Biotechnology, 2005; 118(1):67-740168-16561873-4863http://hdl.handle.net/2440/46446A novel preparation for polyethylene glycol (PEG) derivatives and chromatographic separation procedure of the PEGylated recombinant human granulocyte colony-stimulating factor (rhG-CSF) were designed to evaluate the reproducibility and scalability at large laboratory-scale level. The new “PEG-pellet” PEGylation mode was successfully applied to control the pH fluctuation during the conjugation reaction, a general problem in traditional liquid-phase conjugation mode. Moreover, two consecutive ion-exchange chromatography steps were successfully used to separate and purify the PEGylated rhG-CSF. Cation-exchange chromatography was firstly applied to separate PEGylated rhG-CSF from intact rhG-CSF, followed by anion-exchange chromatography to obtain individual PEG-rhG-CSF species (mono-, di- and tri-PEGylated rhG-CSF) and remove the excess free PEG. Furthermore, the molecular weight of individual PEGylated rhG-CSF was identified by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry and SDS-PAGE, and cell proliferation activity in vitro was detected by MTT assay using NFS-60 cell.enChromatographyPEGylationPoly(ethylene glycol)ProteinrhG-CSFJournal article00200778262008071411483610.1016/j.jbiotec.2005.02.0150002303285000072-s2.0-2044447792144004Bi, J. [0000-0001-7056-8572]