Functionalized liposomes for light-driven H 2 evolution and NADH regeneration Hani M. Elbeheiry and Andrea Pannwitz Institute for Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, Jena, Germany Nowadays, our planet is facing an energy crisis that became very clear in the aftermath of the COVID-19 pandemic in 2021. [1] Accordingly, sustainable approaches towards producing renewable energy are required to tackle this issue. Among these approaches is the solar energy storage in chemical bonds through photocatalytic water splitting into hydrogen (potentially a solar fuel) and oxygen. This process involves two half-reactions: proton reduction and water oxidation. Each half reaction requires three components: a catalyst, a photosensitizer, and an electron donor or electron acceptor. [2,3] In nature, these half-reactions take place in spatially separated compartments achieved by the thylakoid membrane. This compartmentalization minimizes charge recombination and other undesired side reactions. [4] Inspired by nature, we present a lipid bilayer (liposomal) system that performs the reduction half-reactions including hydrogen production and NADH regeneration. This system consists of a rhodium-based catalyst (RhC9), a ruthenium-based photosensitizer (RuC9), ascorbic acid or triethanolamine as electrons, and DPPC as a lipid for liposome construction. The system produces hydrogen with a turnover number of about 180 when irradiated with blue light (453 nm LED) for 8 hours. Additionally, the system successfully reduced NAD to NADH when irradiated with a 455 nm LED as demonstrated by the changes in the UV-visible absorption spectra of the mixture and the characteristic emission of NADH around 445–460 nm. NADH's roles as an electron carrier for ATP production and as a regulator of redox balance make it an essential cellular fuel. [5]
References 1. Global Energy Crisis – Topics - IEA 2. Chem. Eur. J. 2023, 29, e202302284 3. ChemistrySelect 2016, 1, 1405–1409 4. ChemCatChem 2022, 14, e202200484 5. Curr. Opin. Physiol 2018, 3, 101–109
P29
© The Author(s), 2025
Made with FlippingBook Learn more on our blog