Investigation on Site-specific PEGylation of Glucagon-like Peptide-1
ZHANG Lei ZHAI Yan-qin LEI Jian-du MA Guang-hui SU Zhi-guo
Multi-phase Reaction Laboratory, Institute of Process Engineering
Chinese Academic of Science
Multi-phase Reaction Laboratory, Institute of Process Engineering
Chinese Academic of Science
National Laboratoru of Biochemical Engineering, Insitute of Process
Engineering
National Laboratoru of Biochemical Engineering, Insitute of Process
Engineering
National Laboratoru of Biochemical State Key Lab. Biochem. Eng., Inst. Process Eng., Chinese Academy of Sciences State Key Lab. Biochem. Eng., Inst. Process Eng., Chinese Academy of Sciences
Abstract：In order to obtain a more stable PEGylated glucagon-like peptide-1, and prolong its half life, glucagon-like peptide-1 was site-specifically modified with monomethoxy polyethylene glycol succinimidyl carbonate (mPEG-SC, 5000 kDa). It was found that the optimized reaction conditions for maximized bioactivity and the highest modification yield of mono PEGylated GLP-1 were as follows: in 50 mmol/L and pH 7.5 phosphate buffer, concentration of GLP-1 1.0 mg/mL, molar ratio of PEG to GLP-1 2:1, and reaction time 1 h at 4℃. Under the optimized conditions, the mono modification yield reached 50%. Reverse phase high performance liquid chromatography was used to separate and purify mono PEGylated GLP-1 from the reaction mixture. The purity of mono PEGylated glucagon-like peptide-1 was higher than 98%, characterized by gelfiltration chromatography, the bioactivity of mono PEGylated glucagon-like peptide-1 was 86% of the native GLP-1, while its half life in Sprague-Dawley rats was much longer than that of native GLP-1. The mono PEGylated glucagon-like peptide-1 was also stable in aqueous solution.
2009, Vol. 9 
