Carbon Nanotubes Induced Gelation of Unmodified Hyaluronic Acid

Abstract

This work reports an experimental study of the kinetics and mechanisms of gelation of carbon nanotubes (CNTs)-hyaluronic acid (HA) mixtures. These materials are of great interest as functional biogels for future medical applications and tissue engineering. We show that CNTs can induce the gelation of noncovalently modified HA in water. This gelation is associated with a dynamical arrest of a liquid crystal phase separation, as shown by small-angle light scattering and polarized optical microscopy. This phenomenon is reminiscent of arrested phase separations in other colloidal systems in the presence of attractive interactions. The gelation time is found to strongly vary with the concentrations of both HA and CNTs. Near-infrared photoluminescence reveals that the CNTs remain individualized both in fluid and in gel states. It is concluded that the attractive forces interplay are likely weak depletion interactions and not strong van der Waals interactions which could promote CNT rebundling, as observed in other biopolymer-CNT mixtures. The present results clarify the remarkable efficiency of CNT at inducing the gelation of HA, by considering that CNTs easily phase separate as liquid crystals because of their giant aspect ratio.

Investigating linear and nonlinear viscoelastic behaviour and microstructures of gelatin-multiwalled carbon nanotube composites

“…This allows a good transfer of load from the matrix to the filler when the composite is put under mechanical stress, in much the same way that steel bars reinforce concrete 5 . Recently, CNTs have been successfully incorporated into various biopolymer hydrogels including hyaluronic acid in the presence of cross-linking reagent divinyl sulfone 6 or unmodified hyaluronic acid 7 , alginate 8 , chitosan 9,10 , and cyclodextrins…”

A Bioactive Carbon Nanotube‐Based Ink for Printing 2D and 3D Flexible Electronics

“…It is also noteworthy to mention that the high surface area of the SWCNTs enabled them to interact simultaneously with both HA and DNA chains, thereby forming stable printed fibers. [18, 52] The flexibility of these fibers also allowed fiber retraction into the capillary-based nozzle system and facilitated their printability.…”

Injectable and thermoresponsive pericardial matrix derived conductive scaffold for cardiac tissue engineering

“…[23][24][25][26] One of the most challenging aspects of the application of MWCNT is the inherent hydrophobicity resulting in reduced dispersion and rapid aggregation in water. 27 Different strategies have been devised to overcome this problem such as dispersion and ultra-sonication in various solvent systems such as triuoroethanol 28 and ethanol-water mixture 29 or using functionalized CNTs as moist cakes, 30 however, these approaches has met with partial success.…”