This proposal is about the development of sustainable detergency based formulations, based on the blending of biosurfactants and conventional surfactants, and is part of a CASE award funded by EPSRC and Unilever. The focus of the project is to improve our understanding of the interfacial properties of complex multi-component mixtures of biosurfactants and conventional surfactants, and relate those properties to the conditions for optimal performance. We request NR beam time on INTER to progress this project and specifically to study the adsorption behaviour of a 5 component surfactants mixture of the rhamnolipid biosurfactant with nonionic and anionic surfactants at the air-water interface.