Solubilization of Single-Wall Carbon Nanotubes by Supramolecular Encapsulation of Helical Amylose

Abstract

We have developed a simple, efficient process for solubilization of single-wall carbon nanotubes (SWNTs) with amylose in aqueous DMSO. This process requires two important conditions, presonication of SWNTs and subsequent amylose treatment in an optimum mixture of DMSO/H2O. The former step separates SWNT bundles, and the latter step provides a maximum cooperative interaction of SWNTs with amylose, leading to the immediate and complete solubilization. The best solvent condition for this is around 10-20% DMSO, in which amylose assumes a random conformation or an interrupted helix. This indicates that the amylose helix is not the prerequisite for encapsulation of SWNTs. The SEM and AFM images of the encapsulated SWNTs manifest loosely twisted ribbons wrapping around SWNTs, which are locally intertwined as a multiple twist, but no clumps of the host amylose are seen on SWNT capsules.

V-amylose Structural Characteristics, Methods of Preparation, Significance, and Potential Applications

“…(16)(17)(18)20) The V-amylose may be isolated as single-walled Vamylose nanotubes by dispersion of the reaction products in an appropriate solvent such as DMSO or water. (25) Examples of different hydrocarbon types that have been utilized as ligands in the synthesis of the V-amylose include telechelic poly(ε-caprolactone)s (PCLs), (20,22) polyesters, (21) polyethers, (18) and poly(ester-ether)s. (22) This method could be applied for preparation of potential food ingredients by use of food-grade, long carbon chain ingredients.…”

“…(3)(4)(5) The V-amylose complexes have been shown to form with a diverse range of compounds such as alcohols, (6)(7)(8) fatty acids, (9) potassium hydroxide (KOH), (10) iodine, (11) flavor compounds, (12)(13)(14)(15) and hydrophobic organic polymers. (16)(17)(18)(19)(20)(21)(22) V-amylose complexes have shown potential in various food-related applications such as nanoencapsulation of sensitive bioactive (23,24) or flavor compounds, (12,14) formation of amylose nanotubes, (25) and modification of starch rheological functionality. (26,27) Although presently V-amylose in not yet commercially applied as an ingredient in food or pharmaceutical systems, its has been associated with starch functionality modulations that include modification of starch pasting properties, (27,28) reduced retrogradation, (29) and increase of the resistant starch content in starch.…”

Molecular Dynamics of Cellulose Amphiphilicity at the Graphene–Water Interface

“…9 The interaction between amylose and the nonpolar carbon nanotube in aqueous DMSO reflects the amphiphilicity of the polysaccharide. 9 Other possible evidence of hydrophobic effects include the preferred planar orientation of cellulose chains in nanofibers of bacterial cellulose. 10 Single layer graphene has emerged, since its discovery by Geim and Noveselov, 11 as a truly remarkable material.…”

“Helix‐in‐Helix” Superstructure Formation through Encapsulation of Fullerene‐Bound Helical Peptides within a Helical Poly(methyl methacrylate) Cavity

“…However, owing to their rigid and distinct conformational scaffold, a limited number of guest molecules of complementary size and shape can be entrapped in their cavities. Biological helical polymers, such as amylose,2 schizophyllan,3 and assembled proteins,4 are also known to form inclusion complexes with a variety of small molecules and polymers including carbon nanotubes 2a,2b, 3c. Although such biopolymer‐based helical host systems have been well established, it remains challenging to develop synthetic helical polymers with an efficient encapsulation capability for a broad range of guest molecules and polymers 1p, 5…”