title: Functionalized nanostructures: redox-active porphyrin anchors for supramolecular DNA assemblies.
abstract: We have synthesized and studied a supramolecular system comprising a 39-mer DNA with porphyrin-modified thymidine nucleosides anchored to the surface of large unilamellar vesicles (liposomes). Liposome porphyrin binding characteristics, such as orientation, strength, homogeneity, and binding site size, was determined, suggesting that the porphyrin is well suited as a photophysical and redox-active lipid anchor, in comparison to the inert cholesterol anchor commonly used today. Furthermore, the binding characteristics and hybridization capabilities were studied as a function of anchor size and number of anchoring points, properties that are of importance for our future plans to use the addressability of these redox-active nodes in larger DNA-based nanoconstructs. Electron transfer from photoexcited porphyrin to a lipophilic benzoquinone residing in the lipid membrane was characterized by steady-state and time-resolved fluorescence and verified by femtosecond transient absorption.
authors.affiliation: Department of Chemical and Biological Engineering/Physical Chemistry, Chalmers University of Technology, S-41296 Gothenburg, Sweden.
authors.forename: Karl
authors.initials: K
authors.lastname: Börjesson
authors.forename: Joanna
authors.initials: J
authors.lastname: Wiberg
authors.forename: Afaf H
authors.initials: AH
authors.lastname: El-Sagheer
authors.forename: Thomas
authors.initials: T
authors.lastname: Ljungdahl
authors.forename: Jerker
authors.initials: J
authors.lastname: Mårtensson
authors.forename: Tom
authors.initials: T
authors.lastname: Brown
authors.forename: Bengt
authors.initials: B
authors.lastname: Nordén
authors.forename: Bo
authors.initials: B
authors.lastname: Albinsson
mesh_terms: D000480:Alkynes / Q000737:chemistry; D020029:Base Pairing; D016227:Benzoquinones / Q000737:chemistry; D002462:Cell Membrane / Q000737:chemistry; D018736:DNA Adducts / Q000138:chemical synthesis / Q000737:chemistry*; D004579:Electron Transport; D004987:Ethers / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008081:Liposomes / Q000737:chemistry; D008958:Models, Molecular; D036103:Nanotechnology / Q000379:methods*; D009693:Nucleic Acid Hybridization; D011166:Porphyrins / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D000480:Alkynes; D016227:Benzoquinones; D018736:DNA Adducts; D004987:Ethers; D008081:Liposomes; D011166:Porphyrins; C436384:phenyleneethynylene; C004532:quinone