Deconvolving solvent-solvent and drug-solvent diffusion in supramolecular gels

We investigate drug diffusion in supramolecular gels on the molecular level to tailor bespoke drug delivery platforms. We propose to use polarised neutrons on LET to measure the quasi-elastic scattering associated with the diffusive motions of solvent and drug molecules in a prototypical gel. By selective deuteration, individual solvent fractions of the mixed solvent as well as the drug molecule can be distinguished. The data will be analysed (1) by standard models for diffusion in molecular liquids employing simultaneous fits of all momentum transfers, (2) by a fitting approach in terms of susceptibility [A. Arbe et al., Phys Rev Research. 2020], (3) by fully atomistic MD simulations. The result will be a complete picture of the influence of gel fibre surface area on the diffusion of the individual fractions of the solvent, and how this changes in the presence of a solute molecule.