About the Project 

Innovative strategies for the design of eco-sustainable surfactant-based formulations are urgent, as their industrial production is forecast to steadily grow in future years. The vision of the research project CAmBio is a change from the current conventional formulations to new-generation ones based on biosurfactants, amphiphilic biomolecules naturally produced by plants, yeasts, and bacteria. By leveraging a physicochemical approach, CAmBio aims at grounding the fundamental scientific knowledge of the structure and flow dynamics of concentrated biosurfactant self-assemblies. As leading biosurfactants, CAmBio chooses Rhamnolipids (Rha), which are commercially available as mixtures of congeners, all presenting a composite structure including one or two rhamnoses, a carboxylic group, and one or two acyl chains. The complex molecular architecture makes the understanding of the Rha self-aggregation behavior a challenging task. 

The first objective of CAmBio is the investigation of Rha aqueous mixtures (concentrated up to more than 80 wt%). In particular, self-aggregation in the isotropic liquid phases and the emergence of lyotropic liquid crystalline (LLC) phases will be analysed both in static conditions and under flow. The experimental investigation (combining POM, SAXS, dNMR, EPR, and rheology) will be paralleled by a theoretical analysis, with the aim of rationalize the system behavior at a molecular level. Different factors affecting Rha self-aggregation will be analysed, with a specific focus on the protonation state of the carboxylic group, the presence of electrolytes, and the temperature. 

The second objective of CAmBio is the exploration of green chemistry procedures to produce stable Rha microparticles dispersible in water. Based on the knowledge acquired in the first part of the research program we will focus on the possibility of exploiting the liquid-liquid phase separation induced by a controlled process of salting-out, with the aim to clarify the physical determinants of the phenomenon and the system evolution at the various length- and timescales. 

The molecular organization of the biosurfactants within the particle as well as the properties of the particle dispersion will be studied by adopting the same integrated experimental/theoretical physico-chemical strategy set up for the first point. In the last part of the project, to demonstrate that the acquired scientific knowledge fosters the applications of the investigated system, their functional properties will be tested in model formulations such as water-poor detergents, which minimize the environmental impact of packaging and transport, and contaminant absorbents for pollutant removal from wastewater. The active dissemination plan, directed not only to the scientific community, but also to industrial technologists and, more generally, to the civil society, will make the CAmBio project pivotal for a green revolution in the field of formulation chemistry.