Department of Chemistry, University of Rome Sapienza, Rome, Italy.
Colloids Surf B Biointerfaces. 2012 May 1;93:59-66. doi: 10.1016/j.colsurfb.2011.12.008. Epub 2011 Dec 20.
Poly(phenylacetylene) (PPA) and poly(phenylacetylene-co-acrylic acid) (P(PA-co-AA)), nanoparticles bioconjugated with dexamethasone (DXM) during the synthesis, named PPA@DXM and P(PA-co-AA)@DXM, were prepared by a modified surfactant free emulsion method. The loading was studied as a function of different functionality grades of the copolymer and different amounts of drug, obtaining up to 90% of drug loading for P(PA-co-AA)@DXM with 8/1 PA/AA monomer ratio. The SEM images and DLS measurements showed spheres with average diameters in the range 190-500 nm, depending on the content of acrylic acid monomer units in the copolymer and of DXM loading. ζ-potential and surface charge density of DXM loaded nanoparticles were also investigated and confirm the charge density modulation in the range 0.62-2.68σ (μC/m(2)). The results highlight the enhanced capability of our copolymer of hosting DXM, with the advantage of a control of size, surface functionality, charge and release. Moreover we demonstrate for the first time the ability of P(PA-co-AA) DXM loaded nanoparticles to be used in the apoptosis inhibition of human tumor cells (HeLa). On the basis of the results obtained by comparing the effects elicited in HeLa cells by free DXM versus DXM loaded nanoparticles we confirmed the biological efficacy of our preparation.
聚（苯乙炔）（PPA）和聚（苯乙炔-共-丙烯酸）（P（PA-co-AA））纳米粒子在合成过程中与地塞米松（DXM）进行生物共轭，命名为 PPA@DXM 和 P（PA-co-AA）@DXM，是通过改良的无表面活性剂乳液法制备的。研究了载药量作为共聚物不同官能度等级和不同药物剂量的函数，对于 PA/AA 单体比为 8/1 的 P（PA-co-AA）@DXM，载药量高达 90%。SEM 图像和 DLS 测量显示，根据共聚物中丙烯酸单体单元的含量和 DXM 的负载量，球形纳米粒子的平均直径在 190-500nm 范围内。还研究了载药纳米粒子的 ζ-电位和表面电荷密度，并证实了电荷密度在 0.62-2.68σ（μC/m(2)）范围内的调制。这些结果突出了我们的共聚物在宿主 DXM 方面的增强能力，具有控制尺寸、表面功能、电荷和释放的优势。此外，我们首次证明了载有 DXM 的 P（PA-co-AA）纳米粒子在抑制人肿瘤细胞（HeLa）凋亡中的应用能力。通过比较游离 DXM 和载有 DXM 的纳米粒子在 HeLa 细胞中引起的效应，我们根据获得的结果证实了我们制剂的生物学功效。
