Somatostatin containing biodegradable microspheres prepared by a modified solvent evaporation method based on W/O/W-multiple emulsions
Somatostatin containing biodegradable microspheres prepared by a modified solvent evaporation method based on W/O/W-multiple emulsions
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DOI：
10.1016/0378-5173(95)04106-0
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发表时间：
1995-12-29
影响因子：
5.8
通讯作者：
Bodmeier, R
中科院分区：
文献类型：
--
作者：
Herrmann, J;Bodmeier, R
基于多重W/O/W型乳状液的形成，采用改进的溶剂挥发法制备了含肽类药物醋酸生长抑素的可生物降解聚酯微球。所得微球的特征在于相对于药物负载，包封率和形态特征。比较了从微球中提取多肽的各种方法。在所有研究的参数中，影响初级W/O-乳液性质的因素，如相体积比和总体积，是非常重要的。小体积的内水相和中等体积的有机溶剂有利于实现高药物包封率。用乙酸乙酯代替二氯甲烷作为有机溶剂降低了包封效率，并导致更多的多孔微球。除了用非常低分子量的聚合物制备的微球之外，包封效率不受聚合物类型（聚（L-丙交酯）、聚（D，L-丙交酯）、聚（D，L-丙交酯/乙交酯））和分子量的影响。制备条件显著影响微球的形貌和孔隙率。
Biodegradable polyester microspheres containing somatostatin acetate, a peptide drug, were prepared by a modified solvent evaporation method based on the formation of multiple W/O/W-emulsions. The resulting microspheres were characterized with respect to drug loading, encapsulation efficiency and morphological characteristics. Various methods for extracting the peptide from the microspheres were compared. Of all parameters investigated, factors affecting the properties of the primary W/O-emulsion, such as the phase volume ratio and total volume, were of major importance. A small volume of internal aqueous phase and an intermediate volume of organic solvent were favorable to achieve high drug encapsulation efficiencies. Replacing methylene chloride as an organic solvent with ethyl acetate reduced the encapsulation efficiency and resulted in more porous microspheres. Except for microspheres prepared with very low molecular weight polymers, the encapsulation efficiency was not affected by the polymer type (poly(L-lactide), poly(D,L-lactide), poly (D,L-lactide/glycolide)) and molecular weight. The preparation conditions substantially affected the morphology and porosity of the microspheres.