title: Photothermally Triggered Lipid Bilayer Phase Transition and Drug Release from Gold Nanorod and Indocyanine Green Encapsulated Liposomes.
abstract: In light-activated liposomal drug delivery systems (DDSs), the light sensitivity can be obtained by a photothermal agent that converts light energy into heat. Excess heat increases the drug permeability of the lipid bilayer, and drug is released as a result. In this work, two near-IR responsive photothermal agents in a model drug delivery system are studied: either gold nanorods (GNRs) encapsulated inside the liposomes or indocyanine green (ICG) embedded into the lipid bilayer. The liposome system is exposed to light, and the heating effect is studied with fluorescent thermometers: laurdan and CdSe quantum dots (QDs). Both photothermal agents are shown to convert light into heat in an extent to cause a phase transition in the surrounding lipid bilayer. This phase transition is also proven with laurdan generalized polarization (GP). In addition to the heating results, we show that the model drug (calcein) is released from the liposomal cavity with both photothermal agents when the light power is sufficient to cause a phase transition in the lipid bilayer.
authors.affiliation: Department of Chemistry, Aalto University , P.O. Box 16100, FI-00076 Aalto, Finland.
authors.forename: Lauri
authors.initials: L
authors.lastname: Viitala
authors.affiliation: Department of Chemistry, Aalto University , P.O. Box 16100, FI-00076 Aalto, Finland.
authors.forename: Saija
authors.initials: S
authors.lastname: Pajari
authors.affiliation: Faculty of Pharmacy, University of Helsinki , P.O. Box 56, FI-00014 Helsinki, Finland.
authors.forename: Tatu
authors.initials: T
authors.lastname: Lajunen
authors.affiliation: Faculty of Pharmacy, University of Helsinki , P.O. Box 56, FI-00014 Helsinki, Finland.|Department of Pharmaceutics, Utrecht University , Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands.
authors.forename: Leena-Stiina
authors.initials: LS
authors.lastname: Kontturi
authors.affiliation: Faculty of Pharmacy, University of Helsinki , P.O. Box 56, FI-00014 Helsinki, Finland.
authors.forename: Timo
authors.initials: T
authors.lastname: Laaksonen
authors.affiliation: Department of Chemistry, Aalto University , P.O. Box 16100, FI-00076 Aalto, Finland.
authors.forename: Päivi
authors.initials: P
authors.lastname: Kuosmanen
authors.affiliation: Faculty of Pharmacy, University of Helsinki , P.O. Box 56, FI-00014 Helsinki, Finland.
authors.forename: Tapani
authors.initials: T
authors.lastname: Viitala
authors.affiliation: Faculty of Pharmacy, University of Helsinki , P.O. Box 56, FI-00014 Helsinki, Finland.|School of Pharmacy, University of Eastern Finland , P.O. Box 1627, FI-70211 Kuopio, Finland.
authors.forename: Arto
authors.initials: A
authors.lastname: Urtti
authors.affiliation: Department of Chemistry, Aalto University , P.O. Box 16100, FI-00076 Aalto, Finland.
authors.forename: Lasse
authors.initials: L
authors.lastname: Murtomäki
mesh_terms: D002214:Capsules; D065546:Drug Liberation; D006046:Gold / Q000737:chemistry*; D007208:Indocyanine Green / Q000737:chemistry*; D008027:Light; D008051:Lipid Bilayers / Q000737:chemistry*; D008081:Liposomes; D043942:Nanotubes / Q000737:chemistry*; D044367:Phase Transition; D012449:Safety; D013696:Temperature
chemical_list: D002214:Capsules; D008051:Lipid Bilayers; D008081:Liposomes; D006046:Gold; D007208:Indocyanine Green