Kuo, T.-R.T.-R.KuoWu, C.-L.C.-L.WuHsu, C.-T.C.-T.HsuLo, W.W.LoChiang, S.-J.S.-J.ChiangSUNG-JAN LINCHEN-YUAN DONG2022-09-162022-09-1620090142-9612https://www.scopus.com/inward/record.uri?eid=2-s2.0-63649142562&doi=10.1016%2fj.biomaterials.2009.02.003&partnerID=40&md5=15f8c7ea8e612ad82c919864fbda007bhttps://scholars.lib.ntu.edu.tw/handle/123456789/620729The overlapping wavelength of photoluminescence (PL) of zinc oxide nanoparticles (ZnO NPs) and autofluorescence (AF) from the stratum corneum (SC) has for a long time held back researchers from investigating the chemically enhanced penetration pathways of ZnO NPs into the SC lipids. However, the non-linear polarization effect of second harmonic generation (SHG) may be used for ZnO NPs to be distinguished from the AF of the SC. This study combined the SHG of ZnO NPs and the AF of the SC to image the transdermal delivery of ZnO NPs under the chemical enhancer conditions of oleic acid (OA), ethanol (EtOH) and oleic acid-ethanol (OA-EtOH). In addition to qualitative imaging, the microtransport properties of ZnO NPs were quantified to give the enhancements of the vehicle-to-skin partition coefficient (K), the SHG intensity gradient (G) and the effective diffusion path length (L). The results showed that OA, EtOH and OA-EtOH were all capable of enhancing the transdermal delivery of ZnO NPs by increasing the intercellular lipid fluidity or extracting lipids from the SC. © 2009 Elsevier Ltd. All rights reserved.The overlapping wavelength of photoluminescence (PL) of zinc oxide nanoparticles (ZnO NPs) and autofluorescence (AF) from the stratum corneum (SC) has for a long time held back researchers from investigating the chemically enhanced penetration pathways of ZnO NPs into the SC lipids. However, the non-linear polarization effect of second harmonic generation (SHG) may be used for ZnO NPs to be distinguished from the AF of the SC. This study combined the SHG of ZnO NPs and the AF of the SC to image the transdermal delivery of ZnO NPs under the chemical enhancer conditions of oleic acid (OA), ethanol (EtOH) and oleic acid-ethanol (OA-EtOH). In addition to qualitative imaging, the microtransport properties of ZnO NPs were quantified to give the enhancements of the vehicle-to-skin partition coefficient (K), the SHG intensity gradient (G) and the effective diffusion path length (L). The results showed that OA, EtOH and OA-EtOH were all capable of enhancing the transdermal delivery of ZnO NPs by increasing the intercellular lipid fluidity or extracting lipids from the SC. © 2009 Elsevier Ltd. All rights reserved.Chemical enhancer; Second harmonic generation; Transdermal; Two-photon microscopy; ZnO nanoparticles; Acids; Ethanol; Harmonic analysis; Harmonic generation; Lipids; Nanoparticles; Nonlinear optics; Oleic acid; Photons; Semiconducting zinc compounds; Zinc; Zinc oxide; alcohol; lipid; nanoparticle; oleic acid; zinc oxide; animal tissue; article; autofluorescence; controlled study; diffusion; molecular mechanics; mouse; nonhuman; priority journal; skin; stratum corneum; Administration, Cutaneous; Animals; Buffers; Dermatologic Agents; Diffusion; Ethanol; Mice; Mice, Nude; Nanoparticles; Oleic Acid; Particle Size; Skin; Skin Absorption; Zinc Oxidejournal article10.1016/j.biomaterials.2009.02.003192327162-s2.0-63649142562WOS:000266148100005