To understand the chemical kinetics behind the self-division, we used high-performance liquid chromatography (HPLC) to examine the evolution of the concentrations using 65 mM C10 and 10 mM EDC. We monitored the concentration of C10, its corresponding anhydride, and EDC (Fig. ; Fig. ). We found an initial rapid increase in the anhydride concentration simultaneously with a consumption of the EDC. After this initial increase, the anhydride concentration steadily decreased until it disappeared within 30 minutes. This linear decay can be explained by a selfprotection mechanism that we previously documented. In this mechanism, the anhydride is encapsulated and isolated from water, leading to the hydrolysis to occur exclusively on the anhydride that remains in the aqueous medium, resulting in a linear decrease of the anhydride until all droplets have completely dissolved. Such a pattern establishes that the decomposition rate is directly linked to the solubility of the anhydride, which is constant. Using this selfprotection model, we could accurately fit and predict the reaction kinetics described in our reaction cycle (Supplementary Information -Methods). In parallel, we monitored the evolution of the optical density at 600 nm by absorbance measurements in response to various amounts of fuel (Fig. ). The data revealed a rapid, slight increase in turbidity during the first few minutes after 10 mM EDC addition which we attributed to a gradual decrease in turbidity as these droplets hydrolyzed and dissolved. Minutes after, the turbidity decreased back to the original level. The process correlates nicely with the behavior of the system. With 10 mM of EDC, the division was mostly visible by microscopy in the first 10 minutes, backed by the anhydride and turbidity decaying in the first 10 minutes. When more EDC was added, the turbidity increased strongly, indicating the formation of oil droplets in line with our earlier observations (Fig. ). To refer to the production of new vesicles as a division, we ensured that the contents of the mother vesicles were transferred to the daughter vesicles instead of the production of new vesicles outside of the original one. Previous studies have shown that maintaining the integrity of encapsulated materials during vesicle division is a significant challenge, as many systems lose their internal contents due to membrane instability. Thus, we studied various techniques to encapsulate molecules within our multilamellar vesicles (See Supplementary Information -Methods) and found that they can retain fluorescently labeled DNA (Fig. ). Remarkably, these vesicles managed to divide in response to 10 mM EDC and produced daughter vesicles smaller than the parent vesicle, which contained some of the encapsulated labeled DNA after the division. Confocal microscopy experiments (Fig. ; Movie S6) captured this process, where vesicles with Nile Red-stained membranes and encapsulated labeled DNA were observed at various time points after adding 10 mM EDC. At 4 minutes, the vesicles showed partially converted anhydride membranes, indicated by a slight thickening. They increased Nile Red intensity compared to the thinner, intact vesicles (Fig. ). By 10 minutes, small daughter vesicles began forming on the mother vesicle's surface, clearly retaining the encapsulated DNA within their interiors. By 15 minutes, these daughter vesicles slowly detached from the mother vesicle, as shown in the images. Finally, at 17 minutes, the mother vesicle was observed without the daughter vesicles, which had dispersed into the solution and moved out of the focal plane. We also found that EDC at the same concentration can induce inner membrane rearrangements in multilamellar vesicles (Fig. ). This capacity to produce smaller daughter vesicles while preserving the encapsulated contents could have profound implications for developing synthetic cells and studying protocell evolution. We extended our study to decanoic acid (DA), which is considered more prebiotically plausible than C10 and has been much more studied. First, we determined the critical concentration for vesicle formation (CVC) and the optimal pH for vesicle formation (Fig. ). At a concentration of 50 mM DA in 0.2 M MES buffer at pH 6.8, the vesicles were numerous and generally small, not exceeding 50 µm. Unlike the large multilamellar vesicles of C10, DA vesicles were predominantly unilamellar and more abundant (Fig. ). We then investigated the behavior of these vesicles upon the addition of EDC (Fig. ). In line with the data on C10, at 2 minutes after 0.4 mM EDC addition, the Nile Red in the vesicle membrane exhibited increased brightness pointing to the intermolecular anhydride formation. Numerous smaller vesicles in the vicinity also transformed into anhydride droplets (bright points). Additionally, EDC induced an accumulation of anhydride in a specific region of the membrane (indicated by the arrow), which, after 10 minutes, hydrolyzed and formed smaller daughter vesicles. These daughter vesicles detached from the mother vesicle and dispersed into the solution (arrows). At 13 minutes, the mother vesicle underwent internal membrane reorganization, eventually leading to complete division by 24 minutes (Movie S7), demonstrating that the self-division mechanism explored with C10 also functioned effectively with decanoic acid. This finding is significant as it shows the robustness of the condensing agent-induced division mechanism across different amphiphilic systems. In contrast to C10, much less EDC was required to induce a response by the system. For example, turbidimetry measurements at 600 nm with varying EDC concentrations show that as little as 0.4 mM EDC is sufficient to increase the turbidity (Fig. ) compared to the 10 mM EDC required to induce a response for C10 vesicles (Fig. ). We explain the drastic difference between the two seemingly similar amphiphiles by the drastically different nature of the anhydride. Specifically, we expect the anhydride of C10 to be drastically more water-soluble than its DA anhydride counterpart because the anhydride of C10 has an intramolecular anhydride, whereas the C10 anhydride is intermolecular. Therefore, the Carbon number per anhydride is almost twice as high for the anhydride of DA, drastically decreasing solubility. As a result, less anhydride is needed to induce a response. In line with the C10 amphiphiles, the turbidity initially rose and leveled off over the course of an hour. Notably, the pH of the solution remained constant throughout the reaction, ensuring that the observed changes were due to the chemical processes induced by EDC rather than pH fluctuations (Table ). Finally, we explored the reaction in nanometric DA vesicles obtained by extrusion (400 nm). Dynamic light scattering (DLS) analysis quantified the changes in size of these 400 nm multilamellar DA vesicles in the presence of EDC (Fig. ). After extrusion, the vesicles showed a relatively broad peak around 400 nm. One hour after the addition of EDC, the peak at 400 nm was still present but now accompanied by a smaller peak corresponding to vesicles of 50-100 nm in diameter, further corroborating the self-division of the fatty acid vesicles. The coherence between confocal microscopy, turbidimetry, and DLS data underscores the robustness of the chemical conversion mechanism in inducing vesicle division.