Chew N Y, Chan H K
Faculty of Pharmacy, University of Sydney, NSW, Australia.
Pharm Res. 2001 Nov;18(11):1570-7. doi: 10.1023/a:1013082531394.
To study the dispersion performance of non-porous corrugated particles, with a focus on the effect of particle surface morphology on aerosolization of bovine serum albumin (BSA) powders.
The solid-state characteristics of the spray-dried BSA powders, one consisting of smooth spherical particles and another corrugated particles, were characterized by laser diffraction, X-ray powder diffraction, scanning electron microscopy, confocal microscopy, thermogravimetric analysis, surface area analyzer, and buoyancy method. The powders were dispersed using the Rotahaler and the Dinkihaler coupled to a four-stage liquid impinger operating at 30 to 120 L/min. Fine particle fraction (FPF) was expressed as the wt. % of BSA particles of size < or =5 microm collected from the liquid impinger.
Apart from the morphology and morphology-related properties (specific surface area, envelope density), the corrugated particles and spherical particles of BSA had very similar solid-state characteristics (particle size distribution, water content, true density, amorphous nature). Using the Dinkihaler, the FPFs of the corrugated particles were 10-20 wt. % higher than those of the smooth particles. Similar FPF differences were found for the powders dispersed by the Rotahaler, but the relative changes were larger. In addition, the differences were inversely proportional to the air flows (17.3% at 30 L/min, 25.2% at 60 L/min, 13.8% at 90, 8.5% at 120 L/min). Depending on the inhaler, capsule and device retention and impaction loss at the impinger throat were lower for the corrugated particles.
Enhanced aerosol performance of powders can be obtained by surface modification of the particles. The surface asperities of the corrugated particles could lower the true area of contact between the particles, and thus reduce the powder cohesiveness. A distinct advantage of using corrugated particles is that the inhaler choice and air flow become less critical for these particles.
研究无孔波纹颗粒的分散性能，重点关注颗粒表面形态对牛血清白蛋白（BSA）粉末雾化的影响。
采用激光衍射、X射线粉末衍射、扫描电子显微镜、共聚焦显微镜、热重分析、表面积分析仪和浮力法对喷雾干燥的BSA粉末的固态特性进行表征，其中一种粉末由光滑球形颗粒组成，另一种由波纹颗粒组成。使用旋转吸入器和丁基吸入器将粉末分散，并与以30至120 L/min运行的四级液体冲击器相连。细颗粒分数（FPF）表示为从液体冲击器收集的尺寸小于或等于5微米的BSA颗粒的重量百分比。
除形态及与形态相关的特性（比表面积、堆积密度）外，BSA的波纹颗粒和球形颗粒具有非常相似的固态特性（粒度分布、含水量、真密度、无定形性质）。使用丁基吸入器时，波纹颗粒的FPF比光滑颗粒高10%-20%。对于通过旋转吸入器分散的粉末，也发现了类似的FPF差异，但相对变化更大。此外，这些差异与气流成反比（30 L/min时为17.3%，60 L/min时为25.2%，90 L/min时为13.8%，120 L/min时为8.5%）。根据吸入器的不同，波纹颗粒在胶囊和装置中的滞留以及在冲击器喉部的撞击损失较低。
通过颗粒表面改性可提高粉末的雾化性能。波纹颗粒的表面粗糙度可降低颗粒之间的实际接触面积，从而降低粉末的内聚性。使用波纹颗粒的一个明显优势是，对于这些颗粒，吸入器的选择和气流变得不那么关键。
