Faculty of Pharmaceutical Sciences, Life Science Research Center, Josai University, Saitama, Japan.
Biol Pharm Bull. 2012;35(9):1476-86. doi: 10.1248/bpb.b12-00103.
The aim of the present study was to quantitatively evaluate the skin permeation/penetration of nanomaterials and to consider their penetration pathway through skin. Firstly, penetration/permeation of a model fluorescent nanoparticle, Fluoresbrite®, was determined through intact rat skin and several damaged skins. Fluoresbrite® permeated through only needle-punctured skin. The permeation profiles of soluble high molecular compounds, fluorescein isothiocyanate-dextrans (FITC-dextrans, FDs), with different molecular weights were also measured for comparison. The effects of molecular sizes and different skin pretreatments on the skin barrier were determined on the skin penetration/permeation of Fluoresbrite® and FDs. Fluoresbrite® was not permeated the intact skin, but FDs were permeated the skin. The skin distribution of titanium dioxide and zinc oxide nanoparticles was also observed after topical application of commercial cosmetics. Nanoparticles in sunscreen cosmetics were easily distributed into the groove and hair follicles after their topical application, but seldom migrated from the groove or follicles to viable epidermis and dermis. The obtained results suggested that nanoparticles did not permeate intact skin, but permeated pore-created skin. No or little permeation was observed for these nanomaterials through the stratum corneum.
本研究旨在定量评估纳米材料的经皮渗透/穿透性能，并探讨其穿透皮肤的途径。首先，通过完整的大鼠皮肤和几种受损皮肤，测定了模型荧光纳米颗粒 Fluoresbrite®的渗透/穿透情况。Fluoresbrite®仅能穿透针刺过的皮肤。还测量了具有不同分子量的可溶性高分子化合物，异硫氰酸荧光素-葡聚糖（FITC-葡聚糖，FDs）的渗透曲线，以便进行比较。通过测定 Fluoresbrite®和 FDs 的经皮渗透/穿透情况，研究了分子大小和不同皮肤预处理对皮肤屏障的影响。Fluoresbrite®不能渗透完整的皮肤，但 FDs 可以渗透皮肤。在局部应用商业化妆品后，还观察了纳米二氧化钛和纳米氧化锌在皮肤中的分布。防晒霜中的纳米颗粒在局部应用后很容易分布到沟槽和毛囊中，但很少从沟槽或毛囊迁移到有活力的表皮和真皮中。研究结果表明，纳米颗粒不能渗透完整的皮肤，但能渗透微孔化的皮肤。这些纳米材料通过角质层几乎没有或没有渗透。
