Chemical enhancer induced changes in the mechanisms of transdermal delivery of zinc oxide nanoparticles

Department of Chemistry, National Taiwan Normal University, Taipei 116, Taiwan.
Biomaterials (Impact Factor: 8.56). 03/2009; 30(16):3002-8. DOI: 10.1016/j.biomaterials.2009.02.003
Source: PubMed


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.

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Available from: Sung-Jan Lin, Mar 05, 2015
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    • "identified in studies investigating the impact of ultrasound on QD skin penetration (Paliwal et al. 2006). Low frequency entry points can be expanded by certain forms of barrier disruption as was shown in studies investigating the effect of chemical penetration enhancers on ZnO NP skin penetration (Kuo et al. 2009). Lacunar pathways are also found in healthy skin but because of their lower frequency they can be easily missed on tissue histology or TEM. "
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