Biopharmaceutics and Pharmaceutical Technology, Institute of Pharmacy, Ernst-Moritz-Arndt-University of Greifswald, D-17487 Greifswald, Germany.
Eur J Pharm Sci. 2012 Apr 11;45(5):693-7. doi: 10.1016/j.ejps.2012.01.009. Epub 2012 Jan 28.
Magnetizable aerosols can be used for inhalative magnetic drug targeting in order to enhance the drug concentration at a certain target site within the lung. The aim of the present study was to clarify how a typical ferrofluid can be atomized in a reproducible way. The influence of the atomization principle, the concentration of magnetic nanoparticles within the carrier liquid and the addition of commonly used pharmaceutical excipients on the aerosol droplet size were investigated. Iron oxide (magnetite) nanoparticles were synthesized by alkaline precipitation of mixtures of iron(II)- and iron(III)-chloride and coated with citric acid. The resulting ferrofluid was characterized by photon correlation spectroscopy and vibrating sample magnetometry. Two different nebulizers (Pari Boy and eFlow) with different atomization principles were used to generate ferrofluid aerosols. A range of substances that influence the surface tension, viscosity, density or vapor pressure of the ferrofluid were added to investigate their impact on the generated aerosol droplets. The particle size was determined by laser diffraction. A stable ferrofluid with a magnetic core diameter of 10.7 ± 0.45 nm and a hydrodynamic diameter of 124 nm was nebulized by Pari Boy and eFlow. The aerosol droplet size of Pari Boy was approximately 2.5 μm and remained unaffected by the addition of substances that changed the physical properties of the solvent. The droplet size of aerosols generated by eFlow was approximately 5 μm. It was significantly reduced by the addition of Cremophor RH 40, glycerol, polyvinyl pyrrolidone and ethanol.
可磁化气溶胶可用于吸入式磁性药物靶向，以增加肺部特定靶位的药物浓度。本研究的目的是阐明如何以可重复的方式雾化典型的顺磁流体。考察了雾化原理、载液中磁性纳米粒子的浓度以及常用药用辅料的添加对气溶胶液滴大小的影响。通过碱沉淀混合的二价和三价氯化铁合成了氧化铁（磁铁矿）纳米粒子，并涂覆柠檬酸。用光子相关光谱法和振动样品磁强计对所得顺磁流体进行了表征。使用两种不同的雾化器（Pari Boy 和 eFlow），采用不同的雾化原理，生成顺磁流体气溶胶。添加了一系列影响顺磁流体表面张力、粘度、密度或蒸气压的物质，以研究它们对生成气溶胶液滴的影响。通过激光衍射法确定粒径。Pari Boy 和 eFlow 雾化的磁芯直径为 10.7±0.45nm、水动力直径为 124nm 的稳定顺磁流体。Pari Boy 的气溶胶液滴大小约为 2.5μm，添加改变溶剂物理性质的物质后不会发生变化。eFlow 产生的气溶胶的液滴大小约为 5μm，添加吐温 RH40、甘油、聚乙烯吡咯烷酮和乙醇后显著减小。
