Novel Hyaluronic Acid Based Supramolecular Assemblies Stabilized by Multivalent Specific Interactions:  Rheological Behavior in Aqueous Solution

Abstract

The behavior in aqueous medium of new hyaluronic acid (HA) based supramolecular assemblies was fully investigated by rheological measurements. The physical networks studied are stabilized by specific interactions between (i) monomeric -cyclodextrin (CD) and adamantane (AD) molecules or (ii) dimeric CD and AD molecules, each randomly grafted along the polysaccharide chain. The viscoelastic properties of the resulting "mono-and bi-sticker systems", in which inclusion complexes play the role of sticky point, were analyzed as a function of polymer concentration, temperature and addition of host competitive molecules. These networks were shown to exhibit a marked non-Maxwellian behavior. The mono-and bi-interchain complexes considerably slow down the global dynamic and are believed to involve unusual viscoelastic properties that clearly differ from those of alkylated HA-based systems. These rheological features could be explained by a special mechanism of association leading to the formation of networks constituted by double-chain strands connected by fourfold junction points.

Poly-cyclodextrin and poly-paclitaxel nano-assembly for anticancer therapy

“…On average, more than 90% of monomeric PTX/CD complexes dissociated after 100 ns, whereas PTX/pCD and pPTX/pCD displayed only 20-30% PTX/CD pair dissociations after the same time. These data support the conclusion that the stability of the nanoassembly results from the multiplicity of the PTX/CD inclusion complexes formed between the two polymer conjugates 32,33 .…”

Evolution of hierarchical porous structures in supramolecular guest–host hydrogels

“…Independent of these mechanisms, increased multivalence (i.e., increased Ad modification) is known to drastically reduce dynamic rearrangement of guest-host hydrogels as a result of increased polymer avidity and formation of multifold junctions, as examined through prior characterization of bulk relaxation behaviors. 37, 44 Here, reduction in macromolecular dynamics due to increased avidity translated to reduced microstructural rearrangement and hence a reduced pore size. Multivalence also influenced void fraction, likely due to suppressed dynamics that inhibited pore segregation at high polymer concentrations.…”

Supramolecular Polymer Networks: Preparation, Properties, and Potential

“…Instead of using CD dimers for cross-linking, several research groups attached the CDs to a second polymer; in this strategy, mixing of the host-and guestfunctionalized polymers can serve for hydrogel formation [228,229]. When the host and guest molecules are attached to the same polymer, intrachain cross-linking is observed [230].…”