Abstract
Chaotropes are long known to destabilise protein assemblies and folding. We report that a boron cluster ion, as a weakly coordinating superchaotrope, can paradoxically stabilise protein folding even under extended thermal stresses, while broadly inhibiting specific and non-specific protein-protein interactions at millimolar concentrations. Thermodynamic and kinetic investigations suggest that the boron cluster ion reduced the association rates of protein association and rendered protein-associative interactions entropically unfavourable. The preliminary utility of this phenomenon is demonstrated by the preservation of protein functions within complex mixtures stored in ambient, uncontrolled conditions, boosting their shelf-life and stability against aggregation.