Tsuboko Yusuke, Sakoda Hideyuki, Okamoto Yoshihiro, Nomura Yusuke, Yamamoto Eiichi
Division of Medical Devices, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, Japan.
Pharmaceutics. 2024 Nov 20;16(11):1480. doi: 10.3390/pharmaceutics16111480.
This study aims to investigate the impact of test conditions on the results of the compression testing of microneedle arrays (MNAs). Uniaxial compression tests were conducted on polyglycolic acid-fabricated biodegradable MNAs. Load-displacement curves were obtained for varying conditions, including the number of microneedles (MNs) compressed simultaneously, compression speeds, and compression angles. Subsequently, the buckling load and stiffness were calculated, and the MN deformation during compression was observed. The buckling load and stiffness per MN decreased significantly with a simultaneous increase in compressed MNs. The mean buckling load and stiffness of 52 MNs in single-needle compression tests were 0.211 ± 0.008 N and 13.9 ± 1.3 N/mm, respectively, with no variation among the three MNAs. However, a significant difference in buckling load and stiffness was observed among the MNs within the MNAs. Additionally, buckling loads and stiffnesses were significantly lower in certain MNs at the same location in different MNAs. Buckling load and stiffness decreased significantly during inclined compression compared to during vertical compression. While the tests evaluate the mechanical properties of MNAs, test results may vary depending on test conditions. Compression testing of the individual MNs comprising an MNA helps evaluate the mechanical properties of MNs and ensure the quality of MNAs.
本研究旨在探究测试条件对微针阵列（MNAs）压缩测试结果的影响。对聚乙醇酸制造的可生物降解微针阵列进行了单轴压缩测试。针对不同条件获取了载荷-位移曲线，这些条件包括同时压缩的微针数量、压缩速度和压缩角度。随后，计算了屈曲载荷和刚度，并观察了压缩过程中微针的变形情况。随着同时压缩的微针数量增加，每根微针的屈曲载荷和刚度显著降低。在单针压缩测试中，52根微针的平均屈曲载荷和刚度分别为0.211±0.008 N和13.9±1.3 N/mm，三根微针阵列之间无差异。然而，在微针阵列中的微针之间观察到屈曲载荷和刚度存在显著差异。此外，不同微针阵列中相同位置的某些微针的屈曲载荷和刚度明显较低。与垂直压缩相比，倾斜压缩时屈曲载荷和刚度显著降低。虽然这些测试评估了微针阵列的机械性能，但测试结果可能因测试条件而异。对构成微针阵列的单个微针进行压缩测试有助于评估微针的机械性能并确保微针阵列的质量。
