Elastic modulus measurements from individual lactose particles using atomic force microscopy
Elastic modulus measurements from individual lactose particles using atomic force microscopy
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DOI：
10.1016/j.ijpharm.2006.09.032
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发表时间：
2007-03-06
影响因子：
5.8
通讯作者：
Patel, Nikin
中科院分区：
文献类型：
--
作者：
Perkins, Mark;Ebbens, Stephen J.;Patel, Nikin
制药材料的弹性模量影响许多制药工艺和随后的配方性能，目前通过散装方法进行评估，例如压紧物的束弯曲。在这里，我们证明了使用原子力显微镜（AFM）从单晶的优势面（011）精确测量α -一水乳糖的弹性模量为3.45 +/- 0.90 GPa。建立了确保该数据在弹性范围内记录的准则，并可以使用赫兹理论进行建模。我们比较和对比这种AFM方法的永久压痕技术基于一个更大的伯科维奇金字塔压痕在乳糖紧凑型和更广泛的文献。最后，利用原子力显微镜对非晶乳糖的弹性响应进行了研究，结果表明，非晶材料在反复加载下的物理状态发生了变化，在反复的力测量下表现出更结晶的行为，表明压力诱导的相变。所展示的基于AFM的方法具有所需样品最少，不需要生产压块，不需要永久性压痕的非破坏性，并且提供了一种能够检测单个或多个颗粒之间材料特性变化的技术。(c) 2006 Elsevier B.V.版权所有
The elastic modulus of pharmaceutical materials affects a number of pharmaceutical processes and subsequently formulation performance and is currently assessed by bulk methods, such as beam bending of compacts. Here we demonstrate the accurate measurement of the elastic modulus of alpha monohydrate lactose from the dominant (011) face of single crystals using atomic force microscopy (AFM) as 3.45 +/- 0.90 GPa. The criteria to ensure this data is recorded within the elastic limit and can be modelled using Hertzian theory are established. We compare and contrast this AFM method to a permanent indentation technique based upon a much larger Berkovich pyramidal indenter on a lactose compact and the wider literature. Finally the AFM was utilized to study the elastic response of amorphous lactose, demonstrating that the physical state of the amorphous material changes under repeated loading and behaves in a more crystalline manner under repeated force measurements, suggesting a pressure induced phase transition. The AFM based approach demonstrated has the significant advantages of requiring minimal sample, no need for producing a compact, being non-destructive in that no permanent indent is required and providing a technique capable of detecting variations in material properties across a single particle or a number of particles. (c) 2006 Elsevier B.V. All rights reserved.