OBJECTIVE To investigate the preparation and release properties of poly lactid acid(PLA) and poly lactidco glycolide acid (PLG) microspheres (MS) containing tetanus toxoid (TT) protein.METHOD The preparation property and optimum techniques of PLAMS were investigated by microscope and colorimetry using Even's blue, a low molecular weight bio dye as a model encapulating material.According to the optimum techniques,the microspheres containing TT protein were prepared.RESULT During the preparation of microspheres containing TT protein,the loss of TT protein from internal aqueous phase to external aqueous phase occurred and the loss of TT decreased when the concentration of polymer in dichlormethane increased to 25%～30%.The distribution of encapulated TT protein in microspheres was relevant with the weight distribution of different size of microspheres.In vitro,the peak release time of encapulated TT protein was delayed when the diameter of microspheres increased. CONCLUSION The TT proteinloading PLA and PLG microspheres with a smooth and nonporous surface was prepared by optimum techniques.The different size of microspheres containing TT protein can also be prepared for the need of controlled peak release time of encapulated TT protein in vitro and in vivo.
Key words
polymer microspheres /
tetanus toxoid protein /
properties
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References
[1]Haeckel S,Sachse A,Albayrak C，et al. Preparation and characterization of insulin-loaded microcapsules produced by the induced phase separation method[A].In: Preceeding of the second world meeting [C]. APGI/APV Paris，1998:196～200.
[2]Ciftci K,Kas HS,Hincal AA，et al.In vitro and in vivo evaluation of PLAGA(50/50) microspheres containing 5-fluorouracil prepared by a solvent evaporation method[J]. Int J Pharm, 1996，131:73～82.
[3]Cheng A,Gupta RK.Stabilization of tetanus toxoid in poly(DL-lactic-co-glycolic acid) microspheres for the controlled release of antigen[J]. J Pharm Sci, 1996, 85(2):129～132.
[4]Kersten GFA,Gander B.Biodegradable microspheres as vehicles for antigens[A].In:Kaufmann SHE ed. Concepts in Vaccine Development [M].Berlin,New York:Walter de Gruyter & Co,1996:265～302.
[5]Sharif S,O'Hagan DT.A comparison of alternative methods for the determination of the levels of proteins entrapped in (lactide-co-glycolide) microparticles[J]. Inter J Pharm, 1995,115:259～263.
[6]Singh M,Li XM,Mcgee JP, et al. Controlled releases microparticles as single dose hepatitis B vaccine: evaluation of immunogenicity in mice[J]. Vaccine, 1997,15(5):475～481.
[7]Smith PK,Krohn RI,Hermanson GT. et al. Measurement of protein using bicinchoninic acid[J]. Anal Biochem, 1985,150:76～85.
[8]Eldridge JH,Steas J,Meulbroek JA，et al. Biodegradable and biocompatible poly(DL-lactide-co-glycolide) microspheres as an adjuvant for staphylococcal enterotoxin B toxoid which enhances the level of toxin-neutralizing antibodies[J]. Infect Immu, 1991,9:2978～2986.
[9]Jeffery H,Davis SS,O′Hagen DT.The preparation and characterization of poly(lactide-co-glycolide) microspheres.Ⅱ.The entrapment of a model protein using a (water-in-oil)-in-water emulsion by solvent evaporation technique[J]. Pharm Res, 1993,10(3):262～268.
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