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Cross-linked polyurethaneurea films based on polyoxytetramethylene glycol and polyoxypropylene glycol with toluene diisocyanate and 3,3'-dichloro-4,4'-diaminodiphenylmethane were synthesized in a solution where the solvent evaporates during the polymerization. FT-Raman and FTIR spectra were analysed and intermolecular force constants of hydrogen bonds were calculated. On the basis of the intensity of the Raman and IR spectral lines, which reflects hydrogen bond formation, the optimum structure of hydrogen bonds and the conformations of macromolecules of polyurethaneurea were observed for the solvent ethyl acetate. Copyright © 2002 John Wiley & Sons, Ltd.

The modifying effects of the products of the equimolar addition of dl‐alanine and dl‐alanyl‐dl‐alanine to fullerene C60on the structure and permeability of the lipid bilayer of phosphatidylcholine liposomes has been studied using the luminescence probe technique. It is shown that these water soluble amino acid and dipeptide derivatives of fullerene (C60‐AD) are quenchers of pyrene fluorescence and erythrosine phosphorescence of in both a water solution and liposomes. To study the permeability of the lipid bilayer a procedure based on the triplet probe technique has been developed. It has been found that the C60‐AD derivatives under study are able to localize inside the artificial membrane, to penetrate into the liposomes through the lipid bilayer and to perform activated transmembrane transport of bivalent metal ions.

It has been found that the degree of association of the alanylalanine derivative of fullerene in neutral and alkaline media at an ionic strength of 0.1 is virtually independent of the pH of the solution but is a function of only its ionic strength, whereas in acidic media, the pH of the solution has a crucial influence on the degree of association of this fullerene derivative.

It has been shown that in non-aqueous solution amino acid derivatives of [60]fullerene form associates.

IR spectra (4000–400 cm–1) of [60]fullerene monoderivatives of amino acids and dipeptides and several of their methyl esters have been found to differ strongly from those of starting compounds, in that none of them contained the characteristic modes of free C60but instead displayed several new absorptions which indicate the presence of amino acid and peptide moieties in the [60]fullerene derivative molecules, these fragments being in a zwitterion form in most cases.

Amino acid and dipeptide derivatives of [60]fullerene form associates in aqueous solution.

Molecular characteristics of solutions of ω-aminocaproic and p-aminobenzoic derivatives of [60]fullerene in DMSO have been studied by the diffusion method; it has been shown that the molecules form aggregates even in dilute solutions, the degree of aggregation being appreciably dependent both on the nature of the amino acid residue and on the concentration of the solution.