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bioRxiv · 10.1101/2022.05.14.491926

pH-responsive self-assembled compartments as tuneable model protocellular membrane systems

Sarkar, S.·Dagar, S.·Lahiri, K.·Rajamani, S.
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Abstract

Prebiotically plausible single-chain amphiphiles are enticing as model protocellular compartments to study the emergence of cellular life owing to their self-assembling properties. Here, we investigated the self-assembly behaviour of mono-N-dodecyl phosphate (DDP) and mixed systems of DDP with dodecyl 1-dodecanol (DOH) at varying pH conditions. Membranes composed of DDP showed pH-responsive vesicle formation in a wide range of pH with a low critical bilayer concentration (CBC). Further, the addition of DOH to DDP membrane system enhanced vesicle formation and stability in alkaline pH regimes. We also compared the high-temperature behaviour of DDP and DDP-DOH membranes with conventional fatty acid membranes. Both, DDP and DDP:DOH mixed membranes possess packing that is similar to decanoic acid membrane. However, the micropolarity of these systems are similar to phospholipid membranes. Finally, the pH-dependent modulation of different phospholipid membranes doped with DDP was also demonstrated to engineer tuneable membranes with potential translational implications.

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Sarkar, S., Dagar, S., Lahiri, K., Rajamani, S.. 2022-05-14. pH-responsive self-assembled compartments as tuneable model protocellular membrane systems. https://doi.org/10.1101/2022.05.14.491926

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