This project investigates the structural organisation and mechanical behaviour of asymmetric lipid membranes and extracellular vesicle (EV) membrane mimics via molecular dynamics (MD) simulations. This is part of an existing project/grant, CanExCell (Grant agreement ID: 101117487) which aims to develop a lipidomic library of extracellular vesicles (EV’s) derived from cancer cells, investigate their intracellular fate and characterise their interactions with membranes via small angle neutron scattering (SANS) and neutron reflectometry (NR). This will utilise national synchrotron and neutron sources such as the European Spallation Source (ESS), ISIS Neutron, Institut Laue-Langevin (ILL) and MAX IV Laboratory. Cell membranes are primarily composed of phospholipids, amphipathic molecules that self assemble into bilayers with inner and outer leaflets [1]. These membranes contain dynamically regulated biomolecules, such as cholesterol, sphingolipids and proteins, forming a complex heterogeneous cellular membrane network. The distribution of phospholipids and biomolecules between each leaflet is complex, highly asymmetric and heavily determines the biophysical properties of these membranes such as its fluidity, permeability and interactions with surrounding cells [2]. Lipid distribution and membrane composition is vital to the pathophysiology of various diseases. In cancer cells, dysregulation of lipid metabolism alters immune system interactions, drug permeability and metastatic behaviour [3]. All cells, including cancer cells excrete EV’s for cellular communication, EVs contain various biomolecules such as proteins, DNA and RNA encased in a lipid bilayer. Due to their nature of formation, EV’s reflect the highly specific cellular environmental conditions and composition from which they originated from [4]. Understanding how membrane composition and lipid asymmetry alter the mechanical properties of EVs is vital in understanding their role in cancer metastasis and internalisation. Furthermore, due to the similarities between EVs and lipid nanoparticles (LNPs) utilised for biomedical applications, such as vaccines, gene therapies and targeted drug delivery systems, understanding the fundamental mechanics of asymmetric bilayers and EVs aids in the development of LNP based biomedical therapeutics [5, 6]. This project will conduct various atomistic and coarse-grained molecular dynamics simulations of asymmetric bilayers systems that mimic the EVs composition of derived cancer cells. These simulations will elucidate molecular mechanisms that govern lipid organisation, membrane structure and mechanical properties. MD membrane systems will be compared to experimental lipidomic, SANS and NR data gathered through the CanExCell project. The synergistic integration of both computational models and high-resolution experimental analysis will provide new insights into how composition, asymmetry and organisation alter EV biophysics and interactions with cellular membranes. 1. Levental, I. and E. Lyman, Nat Rev Mol Cell Biology, 2023. 24(2):107-122. 2. Ingólfsson, H.I., et al., JACS, 2014. 136(41):14554-14559. 3. Szlasa, W., et al., J Bioenergetics & Biomembranes, 2020. 52(5):321-342. 4. Yáñez-Mó, M., et al., J Extracell Ves, 2015. 4(1):27066. 5. Zylberberg, C., et al., Gene Therapy, 2017. 24(8):441-452. 6. Rahman, M., et al., Nanotechnology-Based Approaches for Targeting and Delivery of Drugs & Genes, V. Mishra, et al., Editors. 2017, Academic Press.151-166.