This proposal aims to investigate the interaction of hydrophobically modified oxidised cellulose nanofibrils (HM-OCNF) with surfactants or soluble starch, in order to find new more environmentally friendly rheology modifiers for possible applications in personal care or agrochemicals. Hydrophobic modification via attachment of C8 or C12 hydrocarbon chains to the cellulose particle surface has been shown to result in greatly enhanced interactions with soluble starch, dramatically increasing the viscosity of these suspensions. Here we wish to determine whether the hydrophobic chains are forming inclusion complexes with the amylose-rich soluble starch, or with micelles to better understand the mechanism of interaction between these species. We will take advantage of selective deuteration of the Cn chain and the solvent to provide scattering contrast in these systems.