The molecular recognition interaction of β-CD with ortho-, meta-, para- aminobenzoic acid isomers was systematically investigated by using steady-state fluorescence spectrum method. The effect of pH value of medium on the inclusion process was discussed in detail. The formation constants of inclusion complexes were determined and the inclusion ability of β-CD to aminobenzoic acid isomers was compared. The related mechanism was proposed. Meanwhile, the inclusion position was studied based on 1D, 2D NMR technique. The relative stereodiagrams of inclusion complexes were proposed by combining molecular dynamics calculation and computer simulation technique. The results obtained from molecular dynamics calculation were in accordance with the results of NMR.

Key words: aminobenzoic acid, molecular recognition, fluorescence spectrum method, NMR