ABSTRACT
@#ObjectiveTo investigate the effect of cryopreservation on the biological activity of the national standard of human granulocyte colony-stimulating factor(hG-CSF)after reconstitution,so as to provide a reference for the use of the national standard of hG-CSF.MethodsThe biological activity of the standard was determined according to the general rule 3525 of Chinese Pharmacopoeia(Volume Ⅲ,2020 edition);The reconstituted hG-CSF national standard was aliquoted and stored at-80 ℃,-40 ℃ and-20 ℃,and then sampled at 1,2,3,5 and 6 months to detect the biological activity. The standards reconstituted before use were used to quantify the standards stored at -80 ℃ for different time durations,and the standards stored at -80 ℃ were defined as the reference of 100% activity to quantify the relative biological activity of the other samples.ResultsThe Eyrlng equation fitted by the thermal acceleration stability experiment was:ln {k(t)} = 6. 75-3 772. 20/T + ln(T),R~2= 0. 969. The biological activity of hG-CSF national standard was predicted to decrease by 5% after about 93. 4 months storage at -80 ℃；The biological activity of reconstituted standards frozen at -80 ℃ decreased by about 24%.ConclusionThe aliquoted reconstituted hG-CSF national standard can be stored at -80 ℃ stably for more than half a year. However,freezing and thawing will cause the activity value to drop by more than 20%,so it is not recommended to reuse after reconstitution.