Division of Molecular Pharmaceutics and Drug Delivery, College of Pharmacy, The University of Texas at Austin, 1 University Station, A1900, Austin, TX, 78712-1200, USA.
Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, TX, 78759, USA.
Drug Deliv Transl Res. 2018 Oct;8(5):1139-1151. doi: 10.1007/s13346-018-0553-1.
For the last several decades, the predominant method for delivering medicine to the surface of the eye has been the standard multiuse eye dropper. While being the most popular, this method has significant limitations. Recently, an effort has been made to explore the use of a directed toroidal vortex or "smoke ring" aerosol delivery system that may help overcome these limitations and enable delivery of precise amounts of formulation and drug to the ocular surface. Promising preliminary in vitro studies indicated dosing control, but the physical characteristics of the toriodal aerosol device performance and impaction forces related to patient comfort have yet to be established. Here, we experimentally investigate the mechanics and dynamics of these ocular aerosol vortices, including translational and rotational velocities, spatial droplet size distributions, and relative impaction forces in order to optimize the device performance and evaluate potential for clinical use. Maximal droplet velocity at various actuation forces was determined, and they were found to be all less than 6 m/s even at the highest actuation forces. Moreover, plume impaction forces were determined across a range of conditions and were all less than about 4.5 μN. Collectively, these studies showed that the physical and mechanical properties of the emitted drug-loaded vortices would be suitable for ocular administration.
在过去的几十年中，将药物递送至眼睛表面的主要方法一直是标准的多用途滴眼器。尽管这种方法最为流行，但它存在着显著的局限性。最近，人们努力探索使用定向环形涡旋或“烟圈”气溶胶输送系统，这可能有助于克服这些局限性，并能够将精确剂量的制剂和药物递送至眼部表面。有前景的初步体外研究表明可以控制剂量，但环形气溶胶装置的物理特性和与患者舒适度相关的撞击力尚待确定。在这里，我们通过实验研究了这些眼部气溶胶涡旋的力学和动力学特性，包括平移和旋转速度、空间液滴尺寸分布以及相对撞击力，以便优化设备性能并评估其临床应用潜力。确定了在各种致动力下的最大液滴速度，并且即使在最高致动力下，它们都小于 6 m/s。此外，还在一系列条件下确定了羽流撞击力，它们均小于约 4.5 μN。总的来说，这些研究表明，所发射的载药涡旋的物理和机械特性将适合眼部给药。
