Konina Kseniia, Freeman Theresa A, Kushner Mark J
Nuclear Engineering and Radiological Sciences Department, University of Michigan, 2355 Bonisteel Blvd., Ann Arbor, MI 48109-2104, United States of America.
Thomas Jefferson University, Philadelphia, PA 19107, United States of America.
Plasma Sources Sci Technol. 2023 Aug 1;32(8):085020. doi: 10.1088/1361-6595/acef59. Epub 2023 Aug 30.
Sterilization of skin prior to surgery is challenged by the reservoir of bacteria that resides in hair follicles. Atmospheric pressure plasma jets (APPJs) have been proposed as a method to treat and deactivate these bacteria as atmospheric plasmas are able to penetrate into structures and crevices with dimensions similar to those found in hair follicles. In this paper, we discuss results from a computational investigation of an APPJ sustained in helium flowing into ambient air, and incident onto a layered dielectric similar to human skin in which there are idealized hair follicles. We found that, depending on the location of the follicle, the bulk ionization wave (IW) incident onto the skin, or the surface IW on the skin, are able to launch IWs into the follicle. The uniformity of treatment of the follicle depends on the location of the of the plasma into the follicle on the top of the skin. Typically, only one side of the follicle is treated on for a given plasma pulse, with uniform treatment resulting from rastering the plasma jet across the follicle over many pulses. Plasma treatment of the follicle is sensitive to the angle of the follicle with respect to the skin, width of the follicle pocket, conductivity of the dermis and thickness of the underlying subcutaneous fat layer, the latter due to the change in capacitance of the tissue.
手术前皮肤的消毒面临着毛囊中细菌储存库的挑战。由于常压等离子体能够渗透到尺寸与毛囊中类似的结构和缝隙中，常压等离子体射流（APPJs）已被提议作为一种治疗和灭活这些细菌的方法。在本文中，我们讨论了对在流入环境空气中的氦气中维持的、并入射到类似于人类皮肤的分层电介质上（其中有理想化毛囊）的常压等离子体射流进行计算研究的结果。我们发现，根据毛囊的位置，入射到皮肤上的体电离波（IW）或皮肤上的表面电离波能够将电离波发射到毛囊中。毛囊治疗的均匀性取决于等离子体进入皮肤顶部毛囊的位置。通常，对于给定的等离子体脉冲，毛囊只有一侧得到治疗，通过在多个脉冲上使等离子体射流在毛囊上进行光栅扫描可实现均匀治疗。毛囊的等离子体治疗对毛囊相对于皮肤的角度、毛囊袋的宽度、真皮的电导率以及下面皮下脂肪层的厚度敏感，后者是由于组织电容的变化。
