Delivering dry powders to the lungs and to the nasal cavity is gaining popularity in the pharmaceutical industry as both targets provide a large surface area for absorption, deliver drugs without affecting the gastrointestinal route, and avoid the patient acceptability problems related to intravenous administration.
干加油吸入剂（DPI）为计量剂量吸入器提供了环保的选择，并且几乎不需要或根本不需要患者的合作，因为患者的呼吸会引起分娩。稳定性也是鼻和肺部递送中干配方的关键优势。
Nevertheless, the development of successful DPIs depend on engineering a powder blend capable of dispersing to a respirable size, typically below 5 µm, which facilitates the drug delivery solely by the inhalation effort of the patient.
一种解决方案涉及使用“载体”颗粒来优化流动和分散行为。yabo214但是，替代的“无载体”解决方案通过沉积和撞击减少了在口腔和喉咙中沉积的材料的量。
开发无载体DPI公式
活性药物成分（API）颗粒的大小必须约为5 µm或更小于靶向肺。yabo214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，颗粒的粒子趋势大yabo214大增加。
因此，有必要修改细胞API颗粒的特性，以最大程度地减少它们之间的凝聚力。yabo214例如，通过增加表面粗糙度来减少粒子表面之间的接触面积是一种方法。最小化颗粒表面能是另一种方法。
成像分析和结果
This article covers the analysis of three samples of salbutamol sulphate coated with different proportions of nano-sized L-leucine crystals using a PVD process in an aerosol flow reactor to explore the effect of varied proportions of L-leucine on the surface topology, particle shape and dispersion behavior of a DPI. The analysis also involved the characterization of a micronised salbutamol sulphate (MSS) sample for comparison.
Morphologi G3, an automated image analysis-based particle characterization system from Malvern Panalytical, was used to assess the particle morphology of each of the samples. Circularity data for the four samples is shown in Figure 1. Particles with circularity close to zero represent a more irregular shape, while circularities closer to one represent a 2D projection with an almost perfect circle.
.jpg)
图1。涂层和未涂层样品的圆形分布，包括代表平均圆形值的颗粒的示例图像。yabo214
结果表明，圆形性随着涂层样品的L-达氨酸比例的增加而降低。相反，MSS样品显示的总循环值最低，并表明存在相当数量的细长颗粒，如图1所示。SEM结果同意，这四个样品的表面形貌和粒子形状不同。yabo214
Analysis of Drug Delivery Characteristics Using Laser Diffraction
.jpg)
图2。Flow-rate dependence of the volume of material below 10 µm in size for each formulation.
SprayTec是一种来自Malvern Allytical的激光衍射系统，用于评估涂层和未涂层样品的雾化特性。使用一个被动吸入器设备在30、60和90 L/min的情况下对每种配方进行测试。
分散的粒径和夹带率都是根据流量的函数分析的。通过在每次启动之前和之后称重吸入器和胶囊，对总发射质量进行重量测量。
.jpg)
图3。S97L03，S91L09，S82L18和MSS的浓度（CV）轮廓，流速为60 l/min。
对于所有三个涂层样品，记录的数据表明，在每个流速下，可重现的可重复的分散剂，如图2所示。该观察结果是由于快速粉末夹带而导致的设备过载的特征。
与涂层样品相反，MSS样品显示出随着流速增加而逐渐提高性能。如图3所示，以60 l/min的流速观察到的样品的浓度分布强调了夹带行为的差异。
表格1。Table showing average emitted mass for each formulation at 30, 60 and 90 L/min, as calculated over three device actuations.
| Flow rate (L/min) |
Emitted mass (mg) |
| S97L03 |
S91L09 |
S91L09 |
MSS |
| 平均的 |
％RSD |
平均的 |
％RSD |
平均的 |
％RSD |
平均的 |
％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 |
对于所有三种涂层材料，夹带都是迅速的，提供了高初始颗粒浓度，可能有利于API向肺部递送。亚博网站下载所有样品的发射质量都随流速而改善，在每种情况下，S82L18的发射质量最高，如表1所示。
Differences in emitted mass are likely to be higher at low flow rates, which deliver a comparatively small amount of energy for entrainment and dispersion of the dose. For the MSS sample, differences in emitted mass are higher at all flow rates, suggesting that break-up and dispersion of the MSS powder bed is comparatively slow and inefficient.
结论
从结果来看，很明显，图像分析和激光衍射的互补技术提供了关键的见解，以更好地了解涂层配方的性能，以操纵控制药物输送的变量。
The results also demonstrate that coating the API with L-leucine nanocrystals is a workable method for altering the properties of the particles in order to optimize the dispersion of carrier-free formulations from passive DPIs.
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提高剂量到剂量的可重复性。yabo214尽管所有涂层配方均表现出高水平的团聚性分散体，但高L-亮氨酸样品的特征似乎更有利于改善递送。
.png)
此信息已从Malvern Panalytical提供的材料中采购，审查和改编。亚博网站下载
For more information on this source, please visitMalvern Alachytical。