title: Solid lipid nanoparticles for delivery of Calendula officinalis extract.
abstract: Solid lipid nanoparticles (SLN) composed of long-chain fatty acids (palmitic acid, stearic acid or arachidic acid), Epikuron 200 (purified phosphatidylcholine), and bile salts (cholate, taurocholate or taurodeoxycholate) have been prepared by dilution of a microemulsion. A total of five different systems were prepared, and characterized by photon correlation spectroscopy, transmission electron microscopy, differential scanning calorimetry, and infrared spectroscopy. The SLN formulation showing optimal properties (lowest size and polydispersity index and highest zeta potential) was obtained with stearic acid and taurodeoxycholate as cosurfactant. This formulation was loaded with Calendula officinalis extract, a natural compound used on ophthalmic formulations given its anti-inflammatory, emollient, and wound repairing activity. Calendula-loaded SLN preparations were characterized in order to determine loading capacity and entrapment efficiency. In vitro cytotoxicity and wound healing efficacy of Calendula-loaded SLN compared to that of a free plant extract were evaluated on a conjunctival epithelium cell line WKD. Our results suggest that this SLN formulation is a safe and solvent-free Calendula extract delivery system which could provide a controlled therapeutic alternative for reducing disease-related symptoms and improving epithelium repair in ocular surface.
authors.affiliation: Unidad de Biofísica (CSIC, UPV/EHU), and Departamento de Bioquímica y Biología Molecular, Universidad del País Vasco (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: Lide
authors.initials: L
authors.lastname: Arana
authors.affiliation: Innoprot, Parque Tecnológico de Bizkaia, Edificio 502, Ibaizabal Bidea, 48160 Elexalde Derio, Spain.
authors.forename: Clarisa
authors.initials: C
authors.lastname: Salado
authors.affiliation: Bioftalmik Applied Research, Bizkaia Science and Technology Park, Building 612, 1st Floor, Astondobidea, Building n° 612, 48160 Derio, Spain.
authors.forename: Sandra
authors.initials: S
authors.lastname: Vega
authors.affiliation: Analytical Chemistry Department, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain.
authors.forename: Oier
authors.initials: O
authors.lastname: Aizpurua-Olaizola
authors.affiliation: Unidad de Biofísica (CSIC, UPV/EHU), and Departamento de Bioquímica y Biología Molecular, Universidad del País Vasco (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: Igor de la
authors.initials: I
authors.lastname: Arada
authors.affiliation: Bioftalmik Applied Research, Bizkaia Science and Technology Park, Building 612, 1st Floor, Astondobidea, Building n° 612, 48160 Derio, Spain.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Suarez
authors.affiliation: Analytical Chemistry Department, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain.
authors.forename: Aresatz
authors.initials: A
authors.lastname: Usobiaga
authors.affiliation: Unidad de Biofísica (CSIC, UPV/EHU), and Departamento de Bioquímica y Biología Molecular, Universidad del País Vasco (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: José Luis R
authors.initials: JLR
authors.lastname: Arrondo
authors.affiliation: Unidad de Biofísica (CSIC, UPV/EHU), and Departamento de Bioquímica y Biología Molecular, Universidad del País Vasco (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: Alicia
authors.initials: A
authors.lastname: Alonso
authors.affiliation: Unidad de Biofísica (CSIC, UPV/EHU), and Departamento de Bioquímica y Biología Molecular, Universidad del País Vasco (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: Félix M
authors.initials: FM
authors.lastname: Goñi
authors.affiliation: Unidad de Biofísica (CSIC, UPV/EHU), and Departamento de Bioquímica y Biología Molecular, Universidad del País Vasco (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain. Electronic address: itzi.alkorta@ehu.es.
authors.forename: Itziar
authors.initials: I
authors.lastname: Alkorta
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000737:chemistry; D001647:Bile Acids and Salts / Q000737:chemistry; D020838:Calendula / Q000737:chemistry*; D003228:Conjunctiva / Q000166:cytology / Q000187:drug effects; D004847:Epithelial Cells / Q000187:drug effects; D005227:Fatty Acids / Q000737:chemistry; D005612:Freeze Drying; D006801:Humans; D008055:Lipids / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D010936:Plant Extracts / Q000008:administration & dosage*; D014945:Wound Healing / Q000187:drug effects
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D001647:Bile Acids and Salts; D005227:Fatty Acids; D008055:Lipids; D010936:Plant Extracts
keywords: Calendula officinalis; Cytotoxicity; Differential scanning calorimetry; Infrared spectroscopy; Re-epithelialization; Solid lipid nanoparticles