title: Chitosan-solid lipid nanoparticles as carriers for topical delivery of tretinoin.
abstract: Tretinoin (TRE) or all-trans retinoic acid is employed in the topical treatment of various skin diseases including acne and psoriasis. However, its use is strongly limited by side effects and high chemical instability. TRE encapsulation in nanostructured systems reduces these problems. Chitosan is a biopolymer that exhibits a number of interesting properties such as bioadhesion and antibacterial activity. The aim of this work was to prepare and characterize solid lipid nanoparticles (SLN) containing TRE, with and without addition of chitosan, to assess their in vitro cytotoxicity in keratinocytes and to evaluate their antibacterial activity against bacteria related to acne. SLN without (SLN-TRE) and with (SLN-chitosan-TRE) chitosan were prepared by hot high pressure homogenization. The hydrodynamic mean diameter and zeta potential were 162.7±1.4 nm and -31.9±2.0 mV for SLN-TRE, and 284.8±15.0 nm and 55.9±3.1 mV for SLN-chitosan-TRE. The SLN-chitosan-TRE exhibited high encapsulation efficiency, high physical stability in the tested period (one year), were not cytotoxic to keratinocytes and showed high antibacterial activity against P. acnes and S. aureus. Therefore chitosan-SLN can be good candidates to encapsulate TRE and to increase its therapeutic efficacy in the topical treatment of acne.
authors.affiliation: Institute of Chemistry, Biological Chemistry Laboratory, Universidade Estadual de Campinas, Campinas, SP, Brazil.
authors.forename: Daniela M
authors.initials: DM
authors.lastname: Ridolfi
authors.forename: Priscyla D
authors.initials: PD
authors.lastname: Marcato
authors.forename: Giselle Z
authors.initials: GZ
authors.lastname: Justo
authors.forename: Lívia
authors.initials: L
authors.lastname: Cordi
authors.forename: Daisy
authors.initials: D
authors.lastname: Machado
authors.forename: Nelson
authors.initials: N
authors.lastname: Durán
mesh_terms: D000152:Acne Vulgaris / Q000188:drug therapy / Q000382:microbiology; D000287:Administration, Topical; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D048271:Chitosan / Q000737:chemistry* / Q000494:pharmacology; D004337:Drug Carriers / Q000737:chemistry; D004339:Drug Compounding; D004355:Drug Stability; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects; D008055:Lipids / Q000737:chemistry; D008826:Microbial Sensitivity Tests; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D011425:Propionibacterium acnes / Q000187:drug effects* / Q000254:growth & development; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development; D014212:Tretinoin / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D004337:Drug Carriers; D008055:Lipids; D014212:Tretinoin; D048271:Chitosan