Supramolecular solubilisation of hydrophilic dyes by using individual dendritic branches

Individual dendritic branches can solubilise hydrophilic dyes in apolar med ia. The functional group at the focal point of the dendritic branch plays a key role in the dye uptake process. Supramolecular interactions between ca rboxylic acid and amine groups have been shown to be effective in enabling efficient solubilisation to occur. The necessary complementarity of this in teraction is further illustrated by a series of control experiments. The ex tent of dendritic branching (i.e. dendritic generation) plays a key role in controlling the extent of dye uptake, with higher-generation dendritic bra nches exhibiting more efficient uptake at lower concentrations. UV/Visible spectroscopic methods have shown that the dendritic branches, in addition t o the tuning of the extent of dye uptake, also tune the optical properties of the solubilised dye and this provides further insight into the interacti ons occurring between the solubilised dye and the individual dendritic bran ches. Furthermore, it is shown that suitably functionalised dendritic branc hes can transport hydrophilic dyes through an apolar phase and deliver them continuously into an aqueous medium.