A Deep-Sea-Inspired Leap in Nanoemulsification
MAGIQ method enables nanoemulsification of ester oils for sustainable cosmetic applications

Researchers at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), POLA Chemical Industries, Inc., and Kyoto University have successfully developed a novel nanoemulsification technology inspired by the extreme environments of deep-sea hydrothermal vents. Their method, known as MAGIQ (Monodisperse nanodroplet generation in quenched hydrothermal solution), enables the formation of ultra-fine oil droplets from ester oils in water, with potential for use in next-generation sustainable cosmetics.

Published online in Journal of Colloid and Interface Science, the study demonstrates how a high-pressure, high-temperature environment—mimicking deep-sea thermal gradients—can be harnessed to nanoemulsify functional oils without significant thermal degradation. This breakthrough is expected to expand the range of biocompatible and eco-conscious ingredients available for cosmetic formulations.

Figure: Schematic illustration of the concept of this study

・A Bottom-Up Approach Inspired by the Deep Sea

Conventional emulsification methods typically follow a 'top-down' approach—physically breaking up large oil droplets. In contrast, MAGIQ takes a “bottom-up” route, where oil molecules spontaneously self-assemble into nanodroplets under precisely controlled hydrothermal conditions. This process draws direct inspiration from the dynamic thermal environments surrounding deep-sea hydrothermal vents, where seawater undergoes rapid heating and quenching across steep thermal gradients.

Using a custom flow-type emulsification reactor, the MAGIQ process limits oil exposure to high temperatures to less than 10 seconds, thereby protecting sensitive ingredients from thermal degradation. Importantly, the method allows the formation of transparent nanoemulsions with droplet diameters around 50 nanometers.

・Ester Oils Nanoemulsified Without Hydrolysis

A key challenge was the application of MAGIQ to ester-based oils, which are widely used in cosmetics but known to hydrolyze under hot aqueous conditions. The research team used molecular dynamics simulations to reveal that ester oils can dissolve at the molecular level in sub–critical/supercritical water, and that this behavior strongly depends on their chemical structure.

Guided by these findings, the team successfully nanoemulsified two ester oils—hexyl dodecanoate and 2-ethylhexyl hexadecanoate—at temperatures above 370°C. Notably, the analysis revealed minimal hydrolysis products (≤100 ppm), indicating that ester functionality was largely retained. This stability is attributed to two key factors: extremely short high-temperature exposure and the unique properties of water near its critical point.

・Toward Sustainable Cosmetic Innovation

This research confirms that a much wider range of oils, including esters, can be processed via MAGIQ than previously thought. This opens new possibilities for formulating high-performance, sustainable cosmetics that make full use of plant-derived functional ingredients.

MAGIQ exemplifies the concept of Deep-Sea-Inspired Chemistry, a research paradigm that seeks innovation by mimicking the extreme physicochemical conditions and adaptive strategies found in the deep ocean. While conventional deep-sea research has often focused on biodiversity and natural history, this new approach aims to translate fundamental deep-sea knowledge into practical technologies.

Such deep-sea-inspired innovations are already being deployed in the food industry, with successful commercialization of polysaccharide emulsifiers produced by similar high-temperature continuous processes. The MAGIQ platform now offers similar promise for cosmetic applications. The deep-sea-inspired approach has also been extended further to fields such as biomanufacturing and plastic recycling.