将干粉末传递到肺部和鼻腔腔正在越来越流行，因为两个靶标都提供了较大的吸收表面积，提供药物而不会影响胃肠道途径，并避免患者可接受性问题与静脉内给药有关。
干加油吸入剂（DPI）为计量剂量吸入器提供了环保选择，并且几乎不需要或根本不需要患者的合作，因为患者的呼吸引起了分娩。稳定性也是鼻和肺部递送中干配方的关键好处。
然而，成功的DPI的发展取决于工程粉混合物，能够分散到可呼吸尺寸的粉末混合物，通常低于5 µm，这仅通过患者的吸入工作来促进药物输送。
一种解决方案涉及使用“载体”颗粒来优化流动和分散行为。欧洲杯猜球平台但是，替代的“无载体”解决方案通过沉积和撞击减少了嘴和喉咙沉积的材料的量。
开发无载体DPI公式
活性药物成分（API）颗粒的大小必须大约为5 µm或更小，以靶向肺部。欧洲杯猜球平台在低于10 µm的尺寸下，由于颗粒跨粒子的吸引力强度的指数增加，颗粒粒子的凝结趋欧洲杯猜球平台势显着增加。
Therefore, it is necessary to modify the properties of fine API particles in order to minimize the cohesive forces between them. Reducing the contact area between particle surfaces, for instance by means of increased surface roughness, is one method. Minimizing particle surface energy is another approach.
Imaging Analyzes and Results
本文介绍了三个分析硫酸硫酸硫酸硫酸硫酸硫磺酸盐，这些样品在气溶胶流动反应器中使用PVD工艺涂有不同比例的纳米大小的L-亮氨酸晶体，从和DPI的分散行为。该分析还涉及对微管盐硫酸盐（MSS）样品的表征进行比较。
形态G3是一种基于图像分析的自动分析粒子表征系统，用于评估每个样品的粒子形态。四个样品的圆周数据如图1所示。圆形接近零的粒子表示更不规则的形状，而接近一个的圆形表示圆形的2D投影几乎是完美的圆。欧洲杯猜球平台
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Figure 1.Circularity distributions for coated and uncoated samples of salbutamol, including example images of particles representing the mean circularity values.
The results demonstrate that circularity reduces with increasing L-leucine proportion for the coated samples. Conversely, the MSS sample shows the lowest overall circularity value and indicates the presence of considerable amount of elongated particles, as shown in Figure 1. SEM results concur that the surface topography and particle shape for the four samples are different.
使用激光衍射分析药物输送特性
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Figure 2.每种公式的尺寸低于10 µm的材料体积的流量率依赖性。
Spraytec, a laser diffraction system from Malvern Panalytical, was used to assess the aerosolization properties of both the coated and uncoated samples. A passive inhaler device was used to perform the tests for each formulation at 30, 60 and 90 L/min.
Both dispersed particle size and entrainment rate were analyzed as a function of flow rate. Gravimetric measurement of total emitted mass was performed by weighing the inhaler and capsule prior to and after each actuation.
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Figure 3.S97L03，S91L09，S82L18和MSS的浓度（CV）轮廓，流速为60 l/min。
For all three coated samples, the recorded data demonstrates good, reproducible dispersion to a respirable size at each flow rate, as illustrated in Figure 2. This observation is characteristic of device overload due to rapid powder entrainment.
Contrary to the coated samples, the MSS sample shows gradually increasing performance with increasing flow rate. Concentration profiles for the samples observed at 60 L/min flow rate emphasize differences in entrainment behavior, as depicted in Figure 3.
表格1。表显示在三个设备作用上计算出的30、60和90 L/min的每个配方的平均发射质量。
| 流速（l/min） |
发射质量（mg） |
| S97L03 |
S91L09 |
S91L09 |
MSS |
| Average |
％RSD |
Average |
％RSD |
Average |
％RSD |
Average |
％RSD |
| 30 |
4.43 |
14.6 |
5.03 |
8.46 |
6.99 |
7.39 |
4.72 |
32.21 |
| 60 |
6.54 |
17.48 |
6.28 |
5.15 |
9.00 |
10.38 |
6.67 |
12.59 |
| 90 |
7.39 |
7.65 |
8.45 |
3.35 |
9.96 |
6.81 |
9.06 |
24.88 |
Entrainment is rapid for all three of the coated materials, providing a high initial particle concentration potentially favoring API delivery to the lungs. Emitted mass improves with flow rate for all samples, with the highest emitted mass recorded for the S82L18 in each case, as shown in Table 1.
在低流量时，发射质量的差异可能会更高，这给剂量的夹带和分散提供了相对较小的能量。对于MSS样本，在所有流速下，发射质量的差异较高，这表明MSS粉末床的分解和分散相对较慢且效率低下。
结论
从the results, it is evident that the complementary techniques of image analysis and laser diffraction provide key insights to better understand the performance of the coated formulations for manipulating the variables that control drug delivery.
结果还表明，用L-达氨酸纳米晶体将API涂覆是一种可行的方法，可更改颗粒的性质，以优化被动DPI的无载体配方的分散。欧洲杯猜球平台
涂层过程最大程度地减少了分散材料所需的能量，从而提高了细颗粒的水平并改善了剂量到剂量的可重复性。欧洲杯猜球平台尽管所有涂层配方均表现出高水平的聚集体分散体，但高L-达氨酸样品的特征似乎更有利地改善递送。
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This information has been sourced, reviewed and adapted from materials provided by Malvern Panalytical.
有关此消息来源的更多信息，请访问Malvern Analytical。