Chew N Y, Bagster D F, Chan H K
Faculty of Pharmacy, University of Sydney, A15, NSW 2006, Sydney, Australia.
Int J Pharm. 2000 Sep 25;206(1-2):75-83. doi: 10.1016/s0378-5173(00)00516-0.
Recently, the dispersion of mannitol powders has demonstrated the importance of particle size, air flow and inhaler device (Chew and Chan, 1999). The aim of the present study is to extend our investigation to a different compound, disodium cromoglycate (DSCG) powders. Solid state characteristics of the powders were assessed by particle sizing, scanning electron microscopy, X-ray powder diffraction, moisture content, particle density determination and freeze fracture. The aerosol behaviour of the powders was studied by dispersion using Rotahaler(R) and Dinkihaler(R), connected to a four-stage liquid impinger operating at 30-120 l/min. Three amorphous powders with a mass median diameter (MMD) of 2.3, 3.7, 5.2 microm and a similar polydispersity were prepared. The particles were nearly spherical with a particle density of 1.6 g/cm(3) and moisture content of 6.6 wt.%. Using Rotahaler(R), the maximum fine particle fraction (FPF(max)) for all three powders was only 15 wt.%, attained at the highest flow of 120 l/min. Using Dinkihaler(R), the FPF(max) was two to four times higher, being 36 and 29 wt.% for the 2.3 and 3.7 microm powder, respectively, at 60 l/min; and 18 wt.% for the 5.2 microm powder at 120 l/min. Hence, the study shows that the FPF in the DSCG powder aerosols was determined by the interaction of the particle size, air flow and inhaler design. The attribution of the amorphous nature and the different physico-chemical properties of the powder may explain the incomplete and low dispersibility of DSCG.
最近，甘露醇粉末的分散情况已表明粒径、气流和吸入装置的重要性（Chew和Chan，1999年）。本研究的目的是将我们的调查扩展到另一种化合物——色甘酸钠（DSCG）粉末。通过粒径分析、扫描电子显微镜、X射线粉末衍射、水分含量、颗粒密度测定和冷冻断裂来评估粉末的固态特性。使用与以30 - 120升/分钟运行的四级液体冲击器相连的Rotahaler®和Dinkihaler®通过分散来研究粉末的气溶胶行为。制备了三种质量中值直径（MMD）分别为2.3、3.7、5.2微米且多分散性相似的无定形粉末。颗粒近乎球形，颗粒密度为1.6克/立方厘米，水分含量为6.6重量%。使用Rotahaler®时，所有三种粉末的最大细颗粒分数（FPF(max)）仅为15重量%，在120升/分钟的最高流速下达到。使用Dinkihaler®时，FPF(max)高出两到四倍，对于2.3微米和3.7微米的粉末，在60升/分钟时分别为36重量%和29重量%；对于5.2微米的粉末，在120升/分钟时为18重量%。因此，该研究表明DSCG粉末气溶胶中的FPF由粒径、气流和吸入器设计的相互作用决定。粉末的无定形性质以及不同的物理化学性质可能解释了DSCG不完全且低分散性的原因。
