title: Lipid-based submicron capsules as a strategy to include high concentrations of a hydrophobic lightening agent in a hydrogel.
abstract: OBJECTIVE
  This study aimed at increasing the concentration of a hydrophobic lightening agent, Omegalight®, in a hydrophilic cosmetic product by means of encapsulation in lipid-based submicron capsules. The core of these capsules is entirely made of the commercial lightening agent.
  
  
  METHODS
  Lipid-based encapsulation systems (LNC) were prepared by the PIT method. Their physicochemical properties were followed over 6 months by dynamic light scattering and zeta potential measurements, and in parallel, the potential degradation of the active ingredient was monitored by HPLC. The stability of the capsules in a cosmetic gel was studied by spectrofluorimetry and rheology measurements. Sensory analysis was used to determine the influence of the presence of capsules in the gel on the consumer's experience.
  
  
  RESULTS
  LNC encapsulating Omegalight®were prepared on a laboratory scale and then on a semi-pilot scale. Their hydrodynamic diameters are around 230 nm. The concentration of Omegalight®in the capsules reaches about 84% w/w, which corresponds to 42% of active ingredient. LNC can be dispersed without degradation at concentrations of up to 20% w/w in a hydrogel without modification of the physicochemical or sensory properties of the gel.
  
  
  CONCLUSIONS
  Lipid-based capsules (LNC), an encapsulation system useful for the epidermal delivery of hydrophobic compounds, were adapted to the encapsulation of a commercial lightening agent. The encapsulation permits the dispersion in a stable manner of a very high concentration of a hydrophobic active molecule in a hydrogel while maintaining the physicochemical and sensory properties of the gel.
authors.affiliation: Université François Rabelais de Tours, EA6295 Nanomédicaments et Nanosondes, 31 avenue Monge, Tours, 37200, France.|Université Grenoble Alpes, DPM, NOVA, UMR CNRS 5063, 470 rue de la Chimie, Saint Martin d'Hères, 38400, France.|CEA Grenoble, LCBM, AFFOND, 17 avenue des Martyrs, Grenoble, 38054, France.
authors.forename: H T P
authors.initials: HTP
authors.lastname: Nguyen
authors.affiliation: Université François Rabelais de Tours, EA6295 Nanomédicaments et Nanosondes, 31 avenue Monge, Tours, 37200, France.
authors.forename: M
authors.initials: M
authors.lastname: Soucé
authors.affiliation: Université François Rabelais de Tours, EA6295 Nanomédicaments et Nanosondes, 31 avenue Monge, Tours, 37200, France.
authors.forename: X
authors.initials: X
authors.lastname: Perse
authors.affiliation: Spincontrol France, 298 rue Giraudeau, Tours, 37000, France.
authors.forename: F
authors.initials: F
authors.lastname: Vial
authors.affiliation: Carlina Technologies, 22, rue Roger Amsler, Angers, 49100, France.
authors.forename: T
authors.initials: T
authors.lastname: Perrier
authors.affiliation: Bioeurope (Solabia Group), Route d'Oulins, Anet, 28260, France.
authors.forename: F
authors.initials: F
authors.lastname: Yvergnaux
authors.affiliation: Université François Rabelais de Tours, EA6295 Nanomédicaments et Nanosondes, 31 avenue Monge, Tours, 37200, France.
authors.forename: I
authors.initials: I
authors.lastname: Chourpa
authors.affiliation: Université François Rabelais de Tours, EA6295 Nanomédicaments et Nanosondes, 31 avenue Monge, Tours, 37200, France.
authors.forename: E
authors.identifier: http://orcid.org/0000-0002-6691-4484
authors.initials: E
authors.lastname: Munnier
mesh_terms: D002851:Chromatography, High Pressure Liquid; D057927:Hydrophobic and Hydrophilic Interactions; D008055:Lipids / Q000737:chemistry*; D011786:Quality Control; D062327:Skin Lightening Preparations / Q000008:administration & dosage*
chemical_list: D008055:Lipids; D062327:Skin Lightening Preparations
keywords: chemical analysis; encapsulation; formulation/stability; skin lightening; spectroscopy