Guillermo Monreal Santiago

Biography

Guillermo Monreal Santiago is an assistant professor (maître de conférences) at the University of Strasbourg in the research unit for Complex Matter Chemistry (CMC), a joint unit of the university and the French National Centre for Scientific Research (CNRS).

His current research interests revolve around coacervates: drawing inspiration from biomolecular condensates (liquid droplets that control different processes in the cell), his team investigates how complex coacervates can be used to direct chemical reactions or self-assembly. Additionally, they develop new techniques to interact with coacervates, aiming to develop new complex systems.

Dr. Monreal Santiago graduated with Honours from the Complutense University of Madrid (Spain) in 2015, with a MSc degree in organic chemistry. He pursued a PhD at the University of Groningen (The Netherlands), on the topics of systems chemistry and de-novo life. Under the supervision of Professor Sijbren Otto, his PhD research involved systems of self-replicating peptides, which he combined with cofactors to observe emergent properties such as protometabolism or compartmentalization. After his graduation in 2020, he continued his career as a postdoctoral researcher in the group of Professor Marleen Kamperman, working on peptide-containing complex coacervates. The focus of his research as a postdoc was to understand the effect of peptide crosslinking on the mechanical properties of coacervates, and to develop new materials that could mimic spider silk. In 2022, he moved to Strasbourg for his current position.

Fellowship 2024

Dates - 01/12/2024-31/12/2026

Project summary

ELECTRICAL AND ELECTROCHEMICAL CONTROL OVER COMPLEX COACERVATION

Complex coacervates are unique liquids: aqueous, yet immiscible with pure water; extremely charge-dense, but hydrophobic. Due to these singular properties, emulsions of coacervate droplets in water have found applications in a variety of fields – from the development of protocells to the food and cosmetic industries. However, a critical drawback prevents their more widespread use: the colloidal stability of coacervate emulsions is very low, meaning that they coalesce into a single phase very shortly after their formation.

The goal of this USIAS project is to explore the use of electric fields to create and stabilize coacervate emulsions, controlling (or completely preventing) their coalescence. This has the potential to open new applications for these colloids, dramatically increasing the time scales that are available for compartmentalization of other molecules or for further stabilization. Additionally, coacervates represent a unique subject for the field of electrohydrodynamics, since their high charge density and low interfacial tension with water make them extremely susceptible to electric fields. For this reason, studying coacervates in this context can lead to new fundamental insights for the physics of electroemulsification and electrocoalescence.

In the project, we will characterize the behaviour of different coacervates under electric fields, with the objective to correlate the observed effects to the coacervate composition and properties. Furthermore, we will develop scaling laws aiming to understand the forces that govern the coacervate-electric field interactions. Finally, we will introduce redox-sensitive groups in the coacervates, making them responsive to electrochemical reactions. Combining electrical forces and electrochemistry, we will work towards developing new systems of unprecedented complexity, exhibiting properties such as transient formation, or electricity-driven transport and pumping.