title: Design of Light-Triggered Lyotropic Liquid Crystal Mesophases and Their Application as Molecular Switches in "On Demand" Release.
abstract: Here, we present the design and assembly of a new light-responsive functional lyotropic liquid crystal system using host-guest lipidic mesophases (LMPs). Light as an external stimulus has many advantages in comparison to other stimuli: it is milder than acids or bases, and variation of intensity and duration can provide a high level of pharmacological control. The LMPs are composed of monoolein (MO) and oleic acid (OA) as host lipids and a small amount of a judiciously synthesized lipid bearing an azobenzene photoactive unit as a guest. While preserving the structure and stability of the host lipidic aggregates, the guest lipids render them specific functionalities. Single-step and sequential light-triggered release and retention of the embedded dye molecules are demonstrated, thereby achieving exquisite temporal, spatial, and dosage control of the release, opening up the possibility of using such lipidic biomaterials as effective matrices in therapy, when a continuous release of active drugs might be toxic.
authors.affiliation: †Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
authors.forename: Simone
authors.initials: S
authors.lastname: Aleandri
authors.affiliation: ‡Department of Health Science and Technology, ETH Zürich, Schmelzbergstrasse 9, LFO, E23 CH-8092 Zürich, Switzerland.
authors.forename: Chiara
authors.initials: C
authors.lastname: Speziale
authors.affiliation: ‡Department of Health Science and Technology, ETH Zürich, Schmelzbergstrasse 9, LFO, E23 CH-8092 Zürich, Switzerland.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Mezzenga
authors.affiliation: †Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
authors.forename: Ehud M
authors.initials: EM
authors.lastname: Landau
mesh_terms: D001391:Azo Compounds / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry; D005989:Glycerides / Q000737:chemistry; D050866:Liquid Crystals / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D019301:Oleic Acid / Q000737:chemistry; D014466:Ultraviolet Rays; D017967:Zinc Compounds / Q000737:chemistry
chemical_list: D001391:Azo Compounds; D002712:Chlorides; D005989:Glycerides; D017967:Zinc Compounds; D019301:Oleic Acid; C016837:zinc chloride; C005953:monoolein; C009850:azobenzene