title: Applications and limitations of lipid nanoparticles in dermal and transdermal drug delivery via the follicular route.
abstract: Lipid nanoparticles (LN) such as solid lipid nanoparticles (SLN) and nanolipid carriers (NLC) feature several claimed benefits for topical drug therapy including biocompatible ingredients, drug release modification, adhesion to the skin, and film formation with subsequent hydration of the superficial skin layers. However, penetration and permeation into and across deeper skin layers are restricted due to the barrier function of the stratum corneum (SC). As different kinds of nanoparticles provide the potential for penetration into hair follicles (HF) LN are applicable drug delivery systems (DDS) for this route in order to enhance the dermal and transdermal bioavailability of active pharmaceutical ingredients (API). Therefore, this review addresses the HF as application site, published formulations of LN which showed follicular penetration (FP), and characterization methods in order to identify and quantify the accumulation of API delivered by the LN in the HF. Since LN are based on lipids that appear in human sebum which is the predominant medium in HF an increased localization of the colloidal carriers as well as a promoted drug release may be assumed. Therefore, sebum-like lipid material and a size of less or equal 640 nm are appropriate specifications for FP of particulate formulations.
authors.affiliation: Institut für Pharmazeutische Technologie, Technische Universität Braunschweig, Mendelssohnstraße 1, 38106 Braunschweig, Germany. Electronic address: a.lauterbach@tu-braunschweig.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Lauterbach
authors.affiliation: Institut für Pharmazeutische Technologie, Technische Universität Braunschweig, Mendelssohnstraße 1, 38106 Braunschweig, Germany. Electronic address: c.mueller-goymann@tu-braunschweig.de.
authors.forename: Christel C
authors.initials: CC
authors.lastname: Müller-Goymann
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D002626:Chemistry, Pharmaceutical / Q000379:methods; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems; D065546:Drug Liberation; D018859:Hair Follicle / Q000378:metabolism*; D006801:Humans; D008055:Lipids / Q000737:chemistry; D053758:Nanoparticles; D004364:Pharmaceutical Preparations / Q000008:administration & dosage / Q000378:metabolism; D012629:Sebum / Q000378:metabolism; D012869:Skin Absorption
chemical_list: D004337:Drug Carriers; D008055:Lipids; D004364:Pharmaceutical Preparations
keywords: Active pharmaceutical ingredient; Dermal drug delivery; Follicular penetration; Hair follicle; Lipid nanoparticle; Nanolipid carrier; Sebum; Solid lipid nanoparticle; Stratum corneum; Transdermal drug delivery