Dainippon Sumitomo Pharma Co., Ltd., Osaka 554-0022, Japan.
Appl Spectrosc. 2014;68(6):625-32. doi: 10.1366/13-07273.
In this study, we investigated molecular-level variation of tablets caused by grinding and its effect on their actual moisture absorbability. Model tablets contained acetaminophen as an active pharmaceutical ingredient and microcrystalline cellulose (MCC) as an excipient. Different levels of grinding were applied during the tablet formulation to intentionally cause the structural variation of the MCC. The moisture absorbability of tablets showed obvious variation depending on the grinding time, and the corresponding change in near-infrared spectra was readily captured. The detailed analysis of the variation of the band frequencies (i.e., wavenumber) revealed that the grinding process substantially disintegrates the crystalline and generates a glassy amorphous structure of MCC, which is a requirement to absorb water molecules. Consequently, it is very likely that the change of the moisture absorbability of the tablets is closely related to the development of the amorphous structure. These results indicate that the pharmaceutical product performances can be influenced by the physical properties of the excipient, which in turn can be controlled by the grinding process.
在这项研究中，我们调查了片剂因研磨引起的分子水平变化及其对实际吸湿能力的影响。模型片剂含有对乙酰氨基酚作为活性药物成分和微晶纤维素（MCC）作为赋形剂。在片剂配方过程中施加不同程度的研磨，有意造成 MCC 的结构变化。片剂的吸湿能力明显取决于研磨时间，并且可以轻易地捕捉到近红外光谱的相应变化。对频带频率（即波数）变化的详细分析表明，研磨过程会使晶体结构完全解体，并生成 MCC 的玻璃态无定形结构，这是吸收水分子的必要条件。因此，片剂吸湿能力的变化很可能与无定形结构的发展密切相关。这些结果表明，药物产品性能可能受到赋形剂物理性质的影响，而这又可以通过研磨过程来控制。
