title: Skin Localization of Lipid Nanoparticles (SLN/NLC): Focusing the Influence of Formulation Parameters.
abstract: BACKGROUND
  In this study, fluorescein labeled SLN and NLC formulations were prepared for improving the dermal distribution of the hydrophilic active ingredients and for enhancing the skin penetration.
  
  
  METHODS
  To determine skin distribution of the lipid nanoparticles ex-vivo penetration/ permeation experiments were performed using full thickness rat skin by means of Franz diffusion cells. Studies on the localization of fluorescence labeled nanoparticles were performed by confocal laser scanning microscopy (CLSM). Cellular uptake studies were performed on human keratinocyte cell line (HaCaT) and visualized by fluorescence microscope. Both tissue and cell uptake were also quantitatively determined by means of fluorimetric method in the skin extract or cell extract.
  
  
  RESULTS
  Both imaging and quantification studies suggest that the dermal localization of the lipid nanoparticles depends on their dimensions and particle size distribution. The CLSM images clearly show that the Tripalmitin based lipid nanoparticles have higher accumulation in the skin. It is possible to overcome the stratum corneum barrier function with T-NLC05 coded lipid nanoparticle formulation. Additionally cellular uptake of this NLC formulation is time dependent. Conclusıon: It can be concluded that this formulation is promising for treating local skin disorders without systemic side effects. On the other hand obtained results suggest that optimum formulation (T-NLC05) might be an interesting option even for novel cosmetic products.
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, Ankara University, P.O. Box: 06100, Tandogan, Ankara, Turkey.
authors.forename: Gulin
authors.initials: G
authors.lastname: Amasya
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Sandri
authors.forename: Arzu
authors.initials: A
authors.lastname: Onay-Besikci
authors.forename: Ulya
authors.initials: U
authors.lastname: Badilli
authors.forename: Carla
authors.initials: C
authors.lastname: Caramella
authors.forename: Maria C
authors.initials: MC
authors.lastname: Bonferoni
authors.forename: Nilufer
authors.initials: N
authors.lastname: Tarimci
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002626:Chemistry, Pharmaceutical; D019793:Fluorescein / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D006801:Humans; D066298:In Vitro Techniques; D015603:Keratinocytes / Q000187:drug effects; D008055:Lipids / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D008297:Male; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry / Q000648:ultrastructure; D017208:Rats, Wistar; D012867:Skin / Q000378:metabolism*; D012869:Skin Absorption
chemical_list: D008055:Lipids; D019793:Fluorescein