The interactions between several peptides with low molecular weight (guest, NH2 Arg Arg Trp Trp H 2; NH2 Arg Trp Arg Trp H 3; NH2 Trp Arg Arg Trp H 4; NH2 Arg Arg Trp Trp Trp Trp H 5; NH2 Trp Trp Arg Arg Trp Trp H 6; ...The interactions between several peptides with low molecular weight (guest, NH2 Arg Arg Trp Trp H 2; NH2 Arg Trp Arg Trp H 3; NH2 Trp Arg Arg Trp H 4; NH2 Arg Arg Trp Trp Trp Trp H 5; NH2 Trp Trp Arg Arg Trp Trp H 6; NH2 Arg Arg Trp Trp Trp Trp Trp Trp H 7; NH2 Arg Arg Trp Trp Trp Trp Trp Trp Trp Trp H 8) and β cyclodextrin dimer (host, 1) bridged with the derivative of (1R, 3R) 1 aminocyclobutane cis 1,3 dicar boxylic acid were investigated by using fluorescence polarization method in buffer aqueous solution (pH 7.4) at 298K. The binding constants of the cyclodextrin dimer 1 to the guests 2 8 were determined. It was shown that there was a cooperative action of the two cavities of a cyclodextrin dimer in the binding of large substrates, and that the structure and properties of amino acid in the peptides played very important roles in the synergic complexation between host and guest.展开更多
A new type of amphiphilic derivative of carboxymethylchitosan(CMCHS) was prepared by reaction of CMCHS with p-nonylphenyl glycidyl ether. The structure of the resulting derivatives, i.e., (2-hydroxyl-3-p-nonylphenoxy)...A new type of amphiphilic derivative of carboxymethylchitosan(CMCHS) was prepared by reaction of CMCHS with p-nonylphenyl glycidyl ether. The structure of the resulting derivatives, i.e., (2-hydroxyl-3-p-nonylphenoxy) propyl-carboxy-methylchitosan(HNP-CMCHS) had been identified by UV and IR spectroscopy. They are water-soluble and have surface activity, which is related to the degree of substitution and the added electrolyte in the solution. In the presence of NaCl, two transitions appeared on the surface tension-concentration plots, that means the possibility of the formation of intramolecular micelle. It was also found that it need a long time for the surface tension of the derivative solutions to get a equilibrium value and the time is related to the derivative concentration, degree of substitution and added electrolyte of the solution.展开更多
文摘The interactions between several peptides with low molecular weight (guest, NH2 Arg Arg Trp Trp H 2; NH2 Arg Trp Arg Trp H 3; NH2 Trp Arg Arg Trp H 4; NH2 Arg Arg Trp Trp Trp Trp H 5; NH2 Trp Trp Arg Arg Trp Trp H 6; NH2 Arg Arg Trp Trp Trp Trp Trp Trp H 7; NH2 Arg Arg Trp Trp Trp Trp Trp Trp Trp Trp H 8) and β cyclodextrin dimer (host, 1) bridged with the derivative of (1R, 3R) 1 aminocyclobutane cis 1,3 dicar boxylic acid were investigated by using fluorescence polarization method in buffer aqueous solution (pH 7.4) at 298K. The binding constants of the cyclodextrin dimer 1 to the guests 2 8 were determined. It was shown that there was a cooperative action of the two cavities of a cyclodextrin dimer in the binding of large substrates, and that the structure and properties of amino acid in the peptides played very important roles in the synergic complexation between host and guest.
文摘A new type of amphiphilic derivative of carboxymethylchitosan(CMCHS) was prepared by reaction of CMCHS with p-nonylphenyl glycidyl ether. The structure of the resulting derivatives, i.e., (2-hydroxyl-3-p-nonylphenoxy) propyl-carboxy-methylchitosan(HNP-CMCHS) had been identified by UV and IR spectroscopy. They are water-soluble and have surface activity, which is related to the degree of substitution and the added electrolyte in the solution. In the presence of NaCl, two transitions appeared on the surface tension-concentration plots, that means the possibility of the formation of intramolecular micelle. It was also found that it need a long time for the surface tension of the derivative solutions to get a equilibrium value and the time is related to the derivative concentration, degree of substitution and added electrolyte of the solution.
