title: Retinyl palmitate flexible polymeric nanocapsules: characterization and permeation studies.
abstract: Polymeric nanocapsules with elastic characteristics were prepared by the pre-formed polymer interfacial deposition method. The system consists of an oily core of retinyl palmitate with Span 60 and a polymeric wall of poly(D,L-lactide) (PLA). A narrow size distribution (215 nm, P.D.I. 0.10) was showed by dynamic light scattering (DLS) analyses. Particle deformability was observed by transmission electron microscopy (TEM) images and permeation of the particles through two superposed membranes of smaller pore diameters. Permeation studies were achieved using plastic surgery abdominal human skin by Franz diffusion cell. Retinyl palmitate permeates into deep skin layers. Besides, a PLA fluorescent derivative conjugated with Nile blue dye by an amide covalent bound was additionally obtained. Permeation profile of the nanocapsules with the fluorescent polymer was evaluated by confocal laser scanning microscopy (CLSM). The CLSM showed that nanocapsules were distributed uniformly, suggesting that the permeation mechanism through skin is intercellular. Thus, the use of these nanocapsules may be a feasible strategy to enhance the permeation of actives into the skin when delivery to deep layers is aimed.
authors.affiliation: Instituto de Química, Universidade Estadual de Campinas, PO Box 6154, Campinas, SP, Brazil.
authors.forename: Zaine
authors.initials: Z
authors.lastname: Teixeira
authors.forename: Beatriz
authors.initials: B
authors.lastname: Zanchetta
authors.forename: Bruna A G
authors.initials: BA
authors.lastname: Melo
authors.forename: Luciana L
authors.initials: LL
authors.lastname: Oliveira
authors.forename: Maria H A
authors.initials: MH
authors.lastname: Santana
authors.forename: Edgar J
authors.initials: EJ
authors.lastname: Paredes-Gamero
authors.forename: Giselle Z
authors.initials: GZ
authors.lastname: Justo
authors.forename: Helena B
authors.initials: HB
authors.lastname: Nader
authors.forename: Sílvia S
authors.initials: SS
authors.lastname: Guterres
authors.forename: Nelson
authors.initials: N
authors.lastname: Durán
mesh_terms: D002214:Capsules; D002851:Chromatography, High Pressure Liquid; D004224:Diterpenes; D004337:Drug Carriers / Q000737:chemistry; D004548:Elasticity; D006801:Humans; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D053769:Nanocapsules / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D011091:Polyesters / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D000084562:Retinyl Esters; D012867:Skin / Q000378:metabolism; D012869:Skin Absorption; D014801:Vitamin A / Q000031:analogs & derivatives* / Q000737:chemistry / Q000493:pharmacokinetics; D014815:Vitamins / Q000737:chemistry / Q000493:pharmacokinetics
chemical_list: D002214:Capsules; D004224:Diterpenes; D004337:Drug Carriers; D053769:Nanocapsules; D011091:Polyesters; D011108:Polymers; D000084562:Retinyl Esters; D014815:Vitamins; D014801:Vitamin A; C014794:retinol palmitate; C033616:poly(lactide)