Abstract: The partition behavior of chlorogenic acid in aqueous two-phase systems containing organic solvent and inorganic salt was studied. Ultraviolet spectrophotometer was used for the qualitative and quantitative determination of chlorogenic acid. The standard curve equation is C=0.67649+21.2607A, R2=0.99824, with the linear range of 51 μg/ml to 55 μg/ml. In this study, the aqueous two-phase systems containing acetone and dipotassium hydrogen phosphate was adopted to extract chlorogenic acid. The effects of quantity of acetone and K2HPO4 ·3H2O on the partition coefficient of chlorogenic acid were investigated. It was found that the optimal extraction conditions of chlorogenic acid with the aqueous two-phase systems are as follows: volume of the aqueous two-phase system 10 ml consisting of acetone 8 ml, water 2 ml and dipotassium hydrogen phosphate 0.8 g. The yield of chlorogenic acid is up to 99.94% under the above conditions. This method easy to restoring, dispose and operate.

Key words: aqueous two-phase systems, chlorogenic acid, acetone, dipotassium hydrogen phosphate