Self-Reproduction of Micelles, Reverse Micelles, and Vesicles: Compartments Disclose a General Transformation Pattern

Abstract

Abstract The discovery of self-reproduction of micelles and vesicles about 15 years ago opened a new page in the field of the supramolecular chemistry of surfactant aggregation phenomena, both for the importance of dynamic aspects of complexity of these systems and for its biological meaning. In fact, the self-reproduction of vesicles has suggested that the growth and the population increase of structures resembling the cells may take place solely because of physical and chemical forces. An increasing number of reports demonstrate that reverse micelles, micelles, sub-micrometric as well as giant vesicles readily undergo self-reproduction, generating new particles from a suitable precursor. The process follows an autocatalytic pattern, namely, the progressive increase in particle number is a nonlinear time course. In this chapter, we will review the most significant studies on the self-reproduction of different compartments, by following a combined historical and classifying approach that spans from the pioneering work on reverse micelles, to the case of normal (aqueous) micelles, to the studies on vesicles, giant vesicles, and water-in-oil emulsion droplets. Similarities and differences in reactive patterns are highlighted, indicating at the same time the unanswered questions. Some of the theoretical models, which have been proposed in the literature to interpret or model self-reproduction of micelles and vesicles, will be illustrated. We will also discuss whether and to what extent such processes comply with the theory of autopoiesis—from which they have been in fact generated, from the historical as well as strategic viewpoint. Finally, we will also shortly discuss the relevance of the self-reproduction of vesicles for emerging avenues of research, in particular for the field of minimal cells, meant as the compartments having the minimal and sufficient complexity to be defined as living.