title: Ionic liquids as ingredients in topical drug delivery systems.
abstract: Because of their properties, ionic liquids (ILs) (Ranke et al.) offer many advantages in topical drug delivery systems. For example, ionic liquids can be used to increase the solubility of sparingly soluble drugs and to enhance their topical and transdermal delivery. Furthermore, ILs can be used either to synthesize active pharmaceutical ingredients or as antimicrobial ingredients. In the present work, the conventional oil-in-water (O/W) and water-in-oil (W/O) emulsions containing the hydrophilic IL [HMIM] [Cl] and the hydrophobic IL [BMIM] [PF6] were prepared, and the influence of the ILs on emulsion properties was evaluated. It was found that ILs could be successfully incorporated into the emulsion structure, resulting in stable formulations. The antimicrobial activity of ILs in the formulations was estimated, and their application as preservatives was confirmed by performing preservative efficacy tests. Evaluation of the in vitro cytotoxicity of the emulsions containing hydrophilic or hydrophobic ILs showed the low cytotoxicity of the carriers. Finally, penetration enhancement of a fluorescent dye as a model drug in the presence of ionic liquids was shown.
authors.affiliation: Technische Hochschule Mittelhessen, University of Applied Science, Institute of Bioprocess Engineering and Pharmaceutical Technology, Wiesenstr. 14, 35390 Giessen, Germany. Dorota.Dobler@kmub.thm.de
authors.forename: Dorota
authors.initials: D
authors.lastname: Dobler
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmidts
authors.forename: Ines
authors.initials: I
authors.lastname: Klingenhöfer
authors.forename: Frank
authors.initials: F
authors.lastname: Runkel
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000494:pharmacology; D016503:Drug Delivery Systems; D004355:Drug Stability; D004655:Emulsions; D005456:Fluorescent Dyes / Q000008:administration & dosage / Q000493:pharmacokinetics; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D052578:Ionic Liquids / Q000737:chemistry* / Q000494:pharmacology; D011310:Preservatives, Pharmaceutical / Q000737:chemistry* / Q000494:pharmacology; D012869:Skin Absorption; D012995:Solubility; D013552:Swine; D018675:Toxicity Tests
chemical_list: D000890:Anti-Infective Agents; D004655:Emulsions; D005456:Fluorescent Dyes; D052578:Ionic Liquids; D011310:Preservatives, Pharmaceutical