| Recombinant Human Granulocyte Colony Stimulating Factor(rhG-CSF)is a DNA Recombination drug of protein/peptide kind,which can stimulate the formation of granulocyte colony,promote the differentiation,multiplication and maturation of leukocyte,prolong the life and strenghthen swallows activeness of mature neutrophilicgranulocyte,rhG-CSF administered by the oral route may be digested by enzyme system and bacteria,with a poor biological availability,so rhG-CSF is administered intramuscularly at present,rhG-CSF may be eliminated quickly in vivo,with a short eliminate half-life.In present study,rhG-CSF was taken as the model drug to prepare pro-liposomes by modern targeted drug delivery technique,liposomes have double-layer Lipid membrane,with fine tissue compatibility,rhG-CSF entrapped in liposomes may Avoid the destruction of enzyme in vivo,and be Released slowly,with a long eliminate half-life.the main results were as follows:1.Study on the preparation methods of rhG-CSF liposomesrhG-CSF liposomes were prepared by the pro-liposomes technique and optimize the optimized formulation were from Orthogomal design The size of the rhG-CSF liposomes was(195.2±40.8)nm;the entrpment efficiency and drug loading were(84.3±0.75)%and (4.95±0.08)%,respectively;The zeta potential was--(45.5±2.97)mV,which attained the predicted objective.2.Study on the determination methods of rhG-CSF liposomesThe determination method of rhG-CSF biological activity by NFS-60 cells was studied in accordance with WHO international standard for G-CSF.Methods.results can guide the study and the manufacture of rhG-CSF effectively.Result of standard curve was Y= 0.28591ogX--0.4806(r=0.9999);RSD of intraday precision was 0.72%,0.47%,0.56%,respectively;RSD of interday precision was 0.75%,0.44%,0.61 %,respectively;Results of recovery rate was(99.21±0.70)%,(99.39±0.61)%,(99.51±0.51)%,and RSD was 0.70%,0.62%,0.52%,respectively.Results of sample recovery rate was(100.1±0.86)%,,(99.8±0.8)%,(100.2±0.73) %,respectively.3.Study on stability and the release behaviorThe rhG-CSF release behavior from rhG-CSF liposomes in vitro was in accord with double phase kinetics model and the equation was as follows:100-Q=0.7361e-0.3064t)+0.9616 e-0.0392t,The rhG-CSF release behavior from rhG-CSF in vitro could be described by first order kinetics model,rhG-CSF liposomes showed significantly Sustained Release characteristic.Adding vitamin E could prevent rhG-CSF liposomes from oxidizing,therefore improve its stability,it showed preferable stability under cold storage(2-8℃),which indicated that rhG-CSF liposomes needed to be stored under cold conditions.4.The Pharmacokinetics experiment on rabbitsrhG-CSF in blood were determined with ABC-ELISA method.The measuring range was 0～4000pg/ml,with high sensitivity,rhG-CSF and rhG-CSF liposomes were all fitted to two compartment model after i.v.administration,t1/2αand t1/2βof rhG-CSF were 0.118 h and 1.786h,respectively;t1/2αand t1/2βof rhG-CSF liposomes were 0.345h和3.518h,respectively;eliminate half-life of rhG-CSF liposomes was remakedly prolonged.Conclusion:rhG-CSF is the biological technology medicine of protein/peptide kind. rhG-CSF administered by the oral route may be digested by enzyme system and bacteria,with a poor biological availability,so rhG-CSF is administered intramuscularly at present,rhG-CSF may be eliminated quickly in vivo,with a short eliminate half-life.Using the pro-liposome techniques,rhG-CSF was entrapped in liposomes,with fine Pharmacokinetics and stability,t1/2βof rhG-CSF liposomes was 3.518h,eliminate half-life of rhG-CSF liposomes was remakedly prolonged.The research of rhG-CSF liposomes provides the science theory basis,has high scientific value and and has not reported at domestic and foreign. |
