Primary Studies On Freeze-dried Goat Embryo Immunoregulatory Factor And Stability

Goat embryo immunoregulatory factor (GEIF) was the biological product developed from goat embryo with the ultrafiltration. In this paper, ultrafiltrated GEIF(molecular weight<3000dalton) was transformed into freeze-dried GEIF using vacuum freeze-drying technology and adding protectants or excipients. Freeze-dying formulation and parameters were optimized. Comparisons of ultrafiltrated GEIF and freeze-dried GEIF, stability of freeze-dried GEIF had also been studied. The results indicated:Mannitol and sucrose could give the appearance to freeze-dried GEIF. The appearance of freeze-dried GEIF varied with the different physical and chemical characters of the protectants. The main difference was shown by the degree of crystalline particles and coarseness.The immunoregulation activity of ultrafiltrated GEIF could be protected by mannitol and sucrose during vacuum freeze-drying. But the effects of each formulation were different. As buffer, sodium citrate did not bring about satisfied stable effect. Considered with the effect of protection and stabilization, 4%(g/ml) mannitol plus 1%(g/ml)sucrose was selected as the optimal formulation.According to the cake appearance , immunoregulation activity and moisture content, the best vacuum freeze-drying parameters were -10 , 25h at the first freeze-drying phase; 20 , 10h at the second freeze-drying phase. The ratio of protectants was the main affecting factor to the protective effect. Both the ratio of protectants and the time of the first freeze-drying phase were the main affecting factors to the stable effect. Amplified manufacture could be on the base of the freeze-drying curve.Ultrafiltrated GEIF and freeze-dried GEIF were compared by ultra-violet scan and HPLC. Both of them had the maximum absorb wavelength around 250 1nm, the absorbvalue<1.5; The HPLC fingerprint of ultrafiltrated GEIF was consistent with that of freeze-dried GEIF. Ret time and relative peak area of the both HPLC fingerprints did not achieved the level of significance (P>0.05). The main ingredients of ultrafiltrated GEIF were not changed by addition of the protectants and lyophilization. The choice of protectants conformed with the theoretic and practical principles. The added excipients did not affect the detections of ultra-violet scan and HPLC of freeze-dried GEIF.Stored at 4 , 20 , 37 for 30d, freeze-dried GEIF was less sensitive to temperature than ultrafiltrated GEIF was. Both of them could keep activity at 4 after 30d;Stored at 20 for 30d, the activity of ultrafiltrated GEIF was worse than that of freeze-dried GEIF; At 37 for 30d, the activity of freeze-dried GEIF was better than that of ultrafiltrated GEIF and the distinction achieved extremely remarkable level(P<0.01). Ultrafiltrated GEIF should store at 2~8 .After storage at RH 90% 5% and RH 75% 5% for 30d, we concluded: freeze-dried GEIF easily absorbed water because of it 's polyporous and rarefaction structure, which caused to lose the good appearance and activity. Freeze-dried GEIF was used qualified package material and packaged well, which could decrease the influence of relative humidity during transport and storage.Primary studies on the stability of freeze-dried GEIF indicated: addition of the protectants and vacuum freeze-drying technology could improve the stability of ultrafiltrated GEIF to some extent.