Controlling the shape of a drop is a revolutionary discovery and will soon enable us to manufacture liquid technology devices in the pharmaceutical and environmental fields. Through the encapsulation of one liquid in another, applications such as the controlled release of drugs, emulsification processes and, for example, the clean-up of spills of liquid pollutants such as oil will be possible.
Researchers at the Politecnico di Milano in collaboration with the Aalto University of Helsinki and the University of Oxford conducted a study on the shape control of droplets consisting of a mixture of water and a protein (hydrophobin).
"While a drop of pure fluid, e.g. of water alone, always retains its initial shape during evaporation, these drops made of a water-hydrophobin mixture, on the other hand, show surprising changes in shape during evaporation"
states Pierangelo Metrangolo from the Department of Chemistry, Materials and Chemical Engineering 'Giulio Natta' at Politecnico.
"In fact, the hydrophobin initially dissolved in water reaches the drop's free surface during evaporation and begins to self-assemble to create a thin film that encapsulates the drop and allows its shape to be controlled thanks to a particular combination of certain gravity conditions and the chemical and mechanical properties of the solute that is unveiled and described by a mathematical model"
Pasquale Ciarletta of the Politecnico di Milano's Department of Mathematics continues.
This research demonstrates the importance of a multidisciplinary approach to drive innovation: the interaction between mathematics and chemistry has enabled the understanding of a new physical phenomenon and its transfer to technology to engineer innovative materials that will revolutionise various industrial applications.
The collaborative work of the authors of the study, Pasquale Ciarletta, Pierangelo Metrangolo and Davide Riccobelli, was funded by Regione Lombardia's NewMed project to create innovative methods and materials for precision and personalised medicine.
The results of these studies have been published in the prestigious scientific journal Physical Review Letters.