Particle size control of proteinoid microsphere formed from monoammonium malate

Abstract

Opalin proposed a chemical evolution hypothesis for the origin of life; Fox and Harada et al. found that heating monoammonium malate salts to form protein-like substances leads to the formation of micron-scale spherical particles called proteinoid microspheres. This process corresponds to the third stage of the chemical evolution theory and is thought to occur under hydrothermal conditions. In this study, the adsorption and uptake of macromolecular substances with fourth-stage functions onto the proteinoid microspheres are observed using organic materials. Since the particles are very small, we investigated the possibility of increasing the size of the particles. As a result, changes in particle size were observed depending on the timing of the addition of KCl and the slow cooling method during the formation of the proteinoid microspheres. The results will be useful for future observations of the proteinoid microspheres.