Ogunjimi Abayomi T, Carr Jamie, Lawson Christine, Ferguson Nkanyezi, Brogden Nicole K
Division of Pharmaceutics and Translational Therapeutics, Department of Pharmaceutical Sciences and Experimental Therapeutics, University of Iowa College of Pharmacy, 180 South Grand Avenue, 552 CPB, Iowa City, IA, 52242-1112, USA.
Department of Dermatology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.
Sci Rep. 2020 Nov 3;10(1):18963. doi: 10.1038/s41598-020-75246-8.
Microneedles (MNs) allow transdermal delivery of skin-impermeable drugs by creating transient epidermal micropores, and micropore lifetime directly affects drug diffusion timeframes. Healthy subjects (n = 111) completed the study, self-identifying as Asian (n = 32), Bi-/multi-racial (n = 10), Black (n = 22), White (n = 23), Latino (n = 23), and Native American/Hawaiian (n = 1). L* was measured with tristimulus colorimetry to objectively describe skin lightness/darkness. MNs were applied to the upper arm; impedance and transepidermal water loss (TEWL) were measured at baseline and post-MN to confirm micropore formation. Impedance was repeated for 4 days to determine micropore lifetime. Post-MN changes in TEWL and impedance were significant in all groups (p < 0.05), confirming micropore formation regardless of skin type. Micropore lifetime was significantly longer in Blacks (66.5 ± 19.5 h) versus Asians (44.1 ± 14.0 h), Bi-/multi-racial (48.0 ± 16.0 h), and Whites (50.2 ± 2.6 h). Latinos (61.1 ± 16.1 h) had significantly longer micropore closure time versus Asians (44.1 ± 14.0 h). When categorizing data according to L*, micropore lifetime was significantly longer in darker skin. We report for the first time that micropore lifetime differences are present in human subjects of different ethnic/racial backgrounds, with longer micropore lifetime in skin of color. These results also suggest that objectively measured skin color is a better predictor of micropore lifetime than self-identified race/ethnicity.
微针（MNs）通过制造短暂的表皮微孔实现皮肤不可渗透药物的经皮递送，而微孔寿命直接影响药物扩散时间。111名健康受试者完成了该研究，他们自我认定为亚洲人（n = 32）、混血/多种族（n = 10）、黑人（n = 22）、白人（n = 23）、拉丁裔（n = 23）和美洲原住民/夏威夷人（n = 1）。采用三刺激比色法测量L以客观描述皮肤的明暗程度。将微针应用于上臂；在基线和微针应用后测量阻抗和经表皮水分流失（TEWL）以确认微孔形成。重复测量阻抗4天以确定微孔寿命。所有组中微针应用后TEWL和阻抗的变化均具有显著性（p < 0.05），证实无论皮肤类型如何均形成了微孔。黑人（66.5±19.5小时）的微孔寿命显著长于亚洲人（44.1±14.0小时）、混血/多种族（48.0±16.0小时）和白人（50.2±2.6小时）。拉丁裔（61.1±16.1小时）的微孔闭合时间显著长于亚洲人（44.1±14.0小时）。根据L对数据进行分类时，肤色较深者的微孔寿命显著更长。我们首次报告不同种族/民族背景的人类受试者存在微孔寿命差异，有色人种皮肤的微孔寿命更长。这些结果还表明，客观测量的肤色比自我认定的种族/民族更能预测微孔寿命。
