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Agarose, ι-, κ-, and λ-carrageenans, and xanthan gum in aqueous solutions interacted with single-walled carbon nanotubes (SWCNTs) as proven by their wetting in solution and by the microRaman spectroscopy, rheological studies, and differential scanning calorimetry. The investigations provided evidence that the effect of complexation of polysaccharides was independent of the possibility of the formation of helical complexes. Complexation involved, to a certain extent, interactions between hydrophobic surface of nanotubes and hydrophobic sides of the saccharide units of polysaccharides. However, clathration of nanotubes in the polysaccharide matrices was also essential. Formation of the clathrate cages involved intra-and intermolecular hydrogen bonds within polysaccharides.ODDZIA£YWANIA POLISACHARYDÓW ANIONOWYCH Z NANORURKAMI WÊGLOWYMI Streszczenie -Agaroza, ι-, κi λkarageny oraz guma ksantanowa (wzór I) w roztworze wodnym oddzia³uj¹ z jednooeciennymi nanorurkami wêglowymi, co potwierdzono analizuj¹c widma Ramana oraz wyniki badañ reologicznych i skaningowej kalorymetrii ró¿nicowej (tabela 1 i 2). Badania dostar-czy³y dowodów na to, ¿e efekt kompleksowania polisacharydów nie zale¿y od mo¿liwooeci otaczania nanorurek helisami polisacharydowymi. Kompleksowanie polega w pewnej mierze na oddzia³ywaniach miêdzy hydrofobow¹ stron¹ merów polisacharydów (rys. 2), a hydrofobow¹ powierzchni¹ nanorurek. Jednak¿e istotne jest te¿ klatratowanie nanorurek w matrycy polisacharydowej. Klatki tworz¹ siê dziêki zarówno wewn¹trz-jak i miêdzycz¹steczkowym oddzia³ywaniom polisacharydów za pooerednictwem wi¹zañ wodorowych. S³owa kluczowe: agaroza, guma ksantanowa, karageny, jednooecienne nanorurki wêglowe, kompleksy polisacharydów z nanorurkami wêglowymi.

Closed-end single-walled carbon nanotubes were wetted in aqueous solutions of monosaccharides, forming weak surface complexes, as proven by the estimation of the content of monosaccharides in complexes isolated from aqueous solutions. The complexation was confirmed by micro-Raman spectroscopy. The Gaussian 03 (Molecular Mechanics UFF method) computations of total energy of the single-walled carbon nanotube-monosaccharides inclusion and surface complexes showed that inclusion complexes should be more stable than corresponding surface complexes. Computed total energies for particular complexes pointed to a lack of preferences for the formation of complexes with either alpha- or beta-tautomers and either pyranoses or furanoses. The forms preferred in the formation of the surface complexes usually differ from these favored in the formation of the inclusion complexes.