包含四氧化三铁纳米粒的聚电解质微囊的制备

本文以生物相容性四氧化三铁纳米粒 (ferrosoferric oxide nanoparticles, Fe₃O₄ NPs) 及聚烯丙基胺盐酸盐 (poly allyamine hydrochloride, PAH) 为囊材, 制备包含Fe₃O₄ NPs的聚电解质微囊。本文采用化学共沉淀法制备Fe₃O₄ NPs, 并对其表观形态、红外光谱、粒径及zeta电位、成膜性能及磁学性质进行考察; 以Fe₃O₄ NPs和PAH作为囊材, 碳酸钙粒子为模板, 通过迭层自组装技术制备聚电解质微囊。结果得到粒径为 (4.9 ± 1.2) μm、分布均匀、饱和磁化强度为8.94 emu·g⁻¹、具有超顺磁性的聚电解质微囊。以罗丹明B异硫氰酸酯标记的牛血清白蛋白 (Rhodamin B isothiocyanate labeled bovine serum albumin, RBITC-BSA) 作为模型药物, 利用囊膜的pH敏感特性将其载入囊内。荧光显微镜观察和包封率测定结果表明, 该聚电解质微囊可成功实现大分子药物的包载, 测得包封率和载药量分别达到 (86.08 ± 3.36) %和 (8.01 ± 0.30) mg·mL⁻¹。

Preparation of polyelectrolyte microcapsules containing ferrosoferric oxide nanoparticles

In this study, polyelectrolyte microcapsules have been fabricated by biocompatible ferrosoferric oxide nanoparticles (Fe₃O₄ NPs) and poly allyamine hydrochloride (PAH) using layer by layer assembly technique.  The Fe₃O₄ NPs were prepared by chemical co-precipitation, and characterized by transmission electron microscopy (TEM) and infrared spectrum (IR).  Quartz cell also was used as a substrate for building multilayer films to evaluate the capability of forming planar film.  The result showed that Fe₃O₄ NPs were selectively deposited on the surface of quartz cell.  Microcapsules containing Fe₃O₄ NPs were fabricated by Fe₃O₄ NPs and PAH alternately self-assembly on calcium carbonate microparticles firstly, then 0.2 mol·L⁻¹ EDTA was used to remove the calcium carbonate.  Scanning electron microscopy (SEM), Zetasizer and vibrating sample magnetometer (VSM) were used to characterize the microcapsule’s morphology, size and magnetic properties.  The result revealed that Fe₃O₄ NPs and PAH were successfully deposited on the surface of CaCO₃ microparticles, the microcapsule manifested superparamagnetism, size and saturation magnetization were 4.9 ± 1.2 μm and 8.94 emu·g⁻¹, respectively.  As a model drug, Rhodamin B isothiocyanate labeled bovine serum albumin (RBITC-BSA) was encapsulated in microcapsule depended on pH sensitive of the microcapsule film.  When pH 5.0, drug add in was 2 mg, the encapsulation efficiency was (86.08 ± 3.36) % and the drug loading was 8.01 ± 0.30 mg·mL⁻¹.