Study On The Quality Standard And Stability Of PEGylated GH

Objective: To develop the quality standard of PEGylated GH and research the stability of PEG-GH solution. Methods: Determine the molecular weight by deox idizeed SDS-PAGE, the purity by Size Exclusion HPLC, Identify the protein by the methods of Western blot and PEG dye, the isoelectric point by IEF, the protein content by lowry. The receptor binding activites were evaluated with their abilitiesto inhibit the binding of ¹²⁵I-hGH to growth homone receptor on the membrance of pregnant rabbit liver cells. whether NaCNBH3 remain, residual free PEG content, were determined by CBBG-250 dye and PEG dye method respectively, and free GH was determined by SE-HPLC. Abortifacient activity and anaphylaxis of PEG-GH are analysed. Put the PEG-GH solution under the temperature of 4℃, 25℃, 37℃,detect the purity,PEG, appearance, PH, bacteria and vitro activity after 0 month,1month,2months,3months and 6months.ReSult: Its molecular weight was 57KD and the protein content was about 1.0mg/ml. Its isoelectric point was 5.2. An excellent separation was achieved for GH and PEG-GH. The assay was validated in the concentration range of 5μg/ml～80μg/ml (r=0.9996). The content of NaCN BH₃ PEG and GH were all up to the standard. The receptor binding activity of the PEG-GH decreased. pH is 6.9. The standard of reliability, according to the sterile experiment, the endotoxin respond experiment, proved that the PEG-GH had no poison side effects. The purity, PEG, appearance and pH of the PEG-GH solution under the temperature of 4℃, 25℃were all up to the stardard. The stability of PEG-GH solution under the temperature of 4℃is good. Conclusion: The developed methods were suitable for the quality control of PEGylated GH and the stability of PEG-GH solution is good.