Partitioning behavior of rutin in novel liquid–liquid biphasic systems formed by choline chloride/ maltose natural deep eutectic solvents and n-propanol

•The novel NADES-based liquid–liquid biphasic systems with ChCl/ Mal NADES and n-propanol were investigated.•The effects of temperature and HBA/HBD molar ratio were investigated to obtain enhanced extraction of rutin.•The hydrogen bonding interaction between NADES and rutin is the main driving tool for rutin partitioning.•Thermodynamic parameters of rutin transfer calculated from the partition data.•Eco-friendly water was used to regenerate NADES. The development of promising environmentally friendly extraction tools has been one of the hottest topics in green chemistry. Among these, natural deep eutectic solvents (NADESs) as green extraction media have received widespread recognition. In this paper, with the aim of exploring the potential applications of NADESs in the extraction field, water-soluble n-propanol was used to form liquid–liquid biphasic systems with choline chloride/ maltose NADESs. The phase behavior of those systems was designed by adjusting the molar proportion of the hydrogen bond acceptors (HBA): hydrogen bond donors (HBD) and temperature. This allows for the systems tailored to the specific requirements of the target molecule, as shown by their application in the extraction of rutin. Investigation of the distribution behavior of rutin suggested that the partition coefficient and the extraction efficiency of rutin in the bottom phase increase significantly with decreasing temperature and increasing HBA: HBD molar ratio. And with the temperature of 288.15 K, the highest TLL of NADES (ChCl: Mal = 1:2) + NPA + water system achieved higher E% of 94.27 %. The interaction force between NADES and rutin was studied using the Hansen solubility parameter, it turned out that Δδi,j of the 2:1 and 1:2 M ratio of NADES was only 8.91, 5.12, which meaning that there may be strong interactions between NADES and rutin. In addition, the hydrogen bond (ΔδH) of the NADES (HBA: HBD = 1:2) was 25.47, which is greater than other interaction force, revealing that the hydrogen bond is the maximum force between rutin and the NADES (HBA: HBD = 1:2). The energy (ΔGT), enthalpy (ΔHT) and entropy (ΔST) calculated from the partition data of rutin was consistent with the free energy (ΔGC), enthalpy (ΔHC) and entropy (ΔSC) changes of system, which confirmed that the driving force of the phase separation of the system drives the transfer of rutin to the lower phase. In addition, we used eco-friendly water to regenerate NADES. The recovery efficiency of rutin was explored