Alignment and photooxidation dynamics of a perylene diimide chromophore in lipid bilayers

Author(s)

Novitasari Sinambela, Richard Jacobi, David Hernández-Castillo, Elisabeth Hofmeister, Nina Hagmeyer, Benjamin Dietzek-Ivanšić, Leticia González, Andrea Pannwitz

Abstract

We present a method of enabling photochemical reactions in water by using biomimetic, water-soluble liposomes and a specifically functionalized perylene diimide chromophore. Linking two flexible saturated C4-alkyl chains with terminal positively charged trimethylammonium groups to the rigid perylene diimide core yielded [1]²⁺ allowing for its co-assembly at the lipid bilayer interface of DOPG liposomes (DOPG = 1,2-dioleoyl-sn-glycero-3-phospho-(1′-rac-glycerol)) with a preferred orientation and in close proximity to the water interface. According to molecular dynamics simulations the chromophore aligns preferably parallel to the membrane surface which is supported by confocal microscopy. Irradiation experiments with visible light and in the presence of a negatively charged, water-soluble oxidant were slower in the DOPG-membrane than under acetonitrile-water reaction conditions. The generated radical species was characterized by EPR spectroscopy in an acetonitrile-water mixture and associated to the DOPG-membrane. Time-resolved emission studies revealed a static quenching process for the initial electron transfer from photoexcited [1]²⁺ to the water soluble oxidant. The findings presented in this study yield design principles for the functionalization of lipid bilayer membranes which will be relevant for the molecular engineering of artificial cellular organelles and nano-reactors based on biomimetic vesicles and membranes.

Organisation(s)

Department of Theoretical Chemistry, Research Platform Accelerating Photoreaction Discovery

External organisation(s)

Universität Ulm, Friedrich-Schiller-Universität Jena, Leibniz-Institut für Photonische Technologien, Vienna Doctoral School in Chemistry (DoSChem)

Journal

Molecular Systems Design and Engineering

Volume

8

Pages

842-852

No. of pages

11

ISSN

2058-9689

DOI

https://doi.org/10.1039/d2me00243d

Publication date

2023

Peer reviewed

Yes

Austrian Fields of Science 2012

104016 Photochemistry, 104017 Physical chemistry

ASJC Scopus subject areas

Chemistry (miscellaneous), Chemical Engineering (miscellaneous), Biomedical Engineering, Energy Engineering and Power Technology, Process Chemistry and Technology, Industrial and Manufacturing Engineering, Materials Chemistry

Portal url

https://ucris.univie.ac.at/portal/en/publications/alignment-and-photooxidation-dynamics-of-a-perylene-diimide-chromophore-in-lipid-bilayers(ef9489a2-7a6e-45bc-9ec4-b27d78d6b85f).html