Development and characterization of CyA-loaded poly(lactic acid)poly(ethylene glycol)PEG micro- and nanoparticles. Comparison with conventional PLA particulate carriers
Development and characterization of CyA-loaded poly(lactic acid)poly(ethylene glycol)PEG micro- and nanoparticles. Comparison with conventional PLA particulate carriers
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DOI：
10.1016/s0939-6411(00)00143-0
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发表时间：
2001-03-01
影响因子：
4.9
通讯作者：
Alonso, MJ
中科院分区：
文献类型：
--
作者：
Gref, R;Quellec, P;Alonso, MJ
采用乳化-溶剂挥发法制备了载环孢菌素A（CyA）的聚乳酸-聚乙二醇（PLA-PEG）微球和纳米球。将这些新型CyA载体的理化性质、肽负载含量和体外释放曲线与常规PLA微米和纳米颗粒相对应的载体进行比较。获得的结果证实了先前描述的PEG链在PLA-PEG制剂表面上的布置。此外，他们揭示了PLA和PLA-PEG系统表面上存在CyA分子。通过用于化学分析的电子光谱法（ESGA）进一步确定表面化学组成，使得我们能够量化纳米球顶层中CyA的量，该量对于纳米颗粒比对于微米颗粒更高，并且对于PLA系统比基于PLA-PEG的那些更高。体外释放实验表明，PLA-PEG颗粒比传统的PLA微米和纳米颗粒提供了更充分的控制CyA释放。释放研究期间系统的物理化学表征表明，开发的PLA和PLA-PEG微米和纳米颗粒未降解，这表明扩散介导的释放机制。此外，我们假设PEG的亲水性外壳为CyA的扩散提供了固定层。(C)2001 Elsevier Science B. V.保留所有权利。
Cyclosporin A (CyA) loaded poly(lactic acid)-poly(ethylene glycol) (PLA-PEG) micro- and nanoparticles have been developed using an emulsion-solvent evaporation method. Physico-chemical properties, peptide loading content and in vitro release profiles of these novel CyA carriers were compared with those corresponding to conventional PLA micro- and nanoparticles. Results obtained confirm the previously described disposition of PEG chains on the surface of the PLA-PEG formulations. In addition, they revealed the presence of CyA molecules on the surface of both PLA and PLA-PEG systems. Further determination of the surface chemical composition by electron spectroscopy for chemical analysis (ESGA) allowed us to quantify the amount of CyA in the nanospheres' top layers, this amount being higher for nanoparticles than for microparticles, and higher for the PLA systems than for those based on PLA-PEG. In vitro release experiments revealed that PLA-PEG particles provided a more adequate control of CyA release than conventional PLA micro- and nanoparticles. Physico-chemical characterization of the systems during the release studies showed that the developed PLA and PLA-PEG micro- and nanoparticles were not degraded, which suggest a diffusion-mediated release mechanism. Furthermore, we have hypothesized that the hydrophilic outer shell of PEG provides a stationary layer for the diffusion of CyA. (C) 2001 Elsevier Science B.V. All rights reserved.