College of Pharmacy, Chungbuk National University, Cheongju, 28160, Republic of Korea.
College of Pharmacy, Wonkwang University, Iksan, 54538, Republic of Korea.
Int J Nanomedicine. 2022 Aug 3;17:3405-3419. doi: 10.2147/IJN.S372582. eCollection 2022.
Dry powder inhalations are an attractive pharmaceutical dosage form. They are environmentally friendly, portable, and physicochemical stable compared to other inhalation forms like pressurized metered-dose inhalers and nebulizers. Sufficient drug deposition of DPIs into the deep lung is required to enhance the therapeutic activity. Nanoscale surface roughness in microparticles could improve aerosolization and aerodynamic performance. This study aimed to prepare microspheres with nanoscale dimples and confirm the effect of roughness on inhalation efficiency.
The dimpled-surface on microspheres (MSs) was achieved by oil in water (O/W) emulsion-solvent evaporation by controlling the stirring rate. The physicochemical properties of MSs were characterized. Also, in vitro aerodynamic performance of MSs was evaluated by particle image velocimetry and computational fluid dynamics.
The particle image velocimetry results showed that dimpled-surface MSs had better aerosolization, about 20% decreased X-axial velocity, and a variable angle, which could improve the aerodynamic performance. Furthermore, it was confirmed that the dimpled surface of MSs could cause movement away from the bronchial surface, which helps the MSs travel into the deep lung using computational fluid dynamics.
The dimpled-surface MSs showed a higher fine particle fraction value compared to smooth-surface MSs in the Andersen Cascade Impactor, and surface roughness like dimples on microspheres could improve aerosolization and lung deposition.
干粉吸入剂是一种有吸引力的药物剂型。与其他吸入形式（如压力定量吸入器和雾化器）相比，干粉吸入剂具有环保、便携和物理化学稳定的特点。为了提高治疗效果，需要将足够的药物沉积到肺部深部。微球的纳米级凹坑表面粗糙度可以改善雾化和空气动力学性能。本研究旨在制备具有纳米级凹坑的微球，并确认粗糙度对吸入效率的影响。
通过控制搅拌速度，用水包油（O/W）乳液-溶剂蒸发法在微球（MSs）上形成凹坑表面。对 MSs 的物理化学性质进行了表征。此外，通过粒子图像测速法和计算流体动力学评估了 MSs 的体外空气动力学性能。
粒子图像测速法的结果表明，凹坑表面 MSs 的雾化效果更好，X 轴速度降低约 20%，角度可变，从而改善了空气动力学性能。此外，还证实了 MSs 的凹坑表面可以使其脱离支气管表面，从而有助于使用计算流体动力学将 MSs 输送到肺部深部。
与光滑表面 MSs 相比，凹坑表面 MSs 在 Andersen 级联撞击器中表现出更高的微细颗粒分数值，并且微球表面的粗糙度（如凹坑）可以改善雾化和肺部沉积。
