The interaction between four peptides with low molecular weight (guest, H-Trp-Trp-Arg-Arg-NH2 3; Adm-Trp-Arg-Arg-NH24; Adm-D-Trp-Arg- Arg-NH25; H-Trp-Trp-Trp-Trp-Arg-Arg-NH26) and cyclodextrin dimers (host, 1,2) bridged with derivatives of glutamic acid or (1R, 3R)-1- aminocyclopentane-cis-1,3-dicarboxylic acid was investigated by using fluorescencepolarization method in aqueous buffer solution (pH 7.4) at 298 K. It was shown that the molecular recognition of a double cyclodextrin to a peptide is not only affected by the structure and properties of the bridging group between two cyclodextrins but also related to the chain length, hydrophobicity of a peptide and polarity, size and shape of the penetrating group. The changes in enthalpy (△ H^0) and entropy (T△S^0) accompanying the complexation were determined in usual way. It was found that complexation is accompanied by negative changes in enthalpy and positive changes in entropy, indicating that van der Waals-Lodon dispersion, hydrogen bonding and hydrophobic interaction between a double cyclodextrin and a peptide are mainly responsiblefor the inclusion compound formation.

Key words: AMINO ACID, CYCLODEXTRIN, DIMER, OLECULAR RECOGNITION, POLYPEPTIDE, CLATHRATES