Sugars as hydrogen-bond donors tune the phase behavior in a novel liquid–liquid biphasic system formed by hydrophilic deep eutectic solvents and n-propanol

•A novel DES-based liquid–liquid biphasic system was constructed.•Chemical structure of HBD was evaluated for phase behavior.•Initial molar ratio of DES in the two phases was maintained.•NRTL model was applied to calculate the experimental tie-lines data.•Salting-out ability of HBD affected the distribution of biomolecule probes.