The structural anisotropy and shear rheology of colloidal gels under startup of shear flow are calculated by Brownian Dynamics simulations modified to include particle surface-mediated attractions, which is a model for thermoreversible colloidal gels. Shear-induced structural changes are analyzed in both real and reciprocal space through computation of the pair distribution function and structu...

Metallo supramolecular assemblies of an 8-arm poly(ethylene glycol) partially substituted with terpyridyl end-groups and the transition metal ions Ni(2+), Fe(2+), Co(2+) and Zn(2+) were studied for their nano-particle formation at dilute conditions and gelation at higher concentrations. The large differences in dissociation rate constants of the metal ligand complexes largely determine the asse...

Coarsening and kinetic arrest of colloidal systems undergoing spinodal decomposition (SD) is a conserved motif for forming hierarchical, bicontinuous structures. Although the thermodynamic origins of SD in colloids are widely known, the microstructural processes responsible for its coarsening and associated dynamics en route to arrest remain elusive. To better elucidate the underlying large-sca...

We have shown that the lattice fluid hydrogen bond ~LFHB! model can successfully quantify the first-order volume transition in hydrogels. The model predicts that a critical balance of hydrophilic and hydrophobic interactions is required for a gel to exhibit a discontinuous volume transition. In this work we will report the swelling behavior of a new thermoreversible copolymer hydrogel, which ha...

A cationic bis-imidazolium-based amphiphile was used to form thermoreversible nanostructured supramolecular hydrogels incorporating neutral and cationic drugs for the topical treatment of rosacea. The concentration of the gelator and the type and concentration of the drug incorporated were found to be factors that strongly influenced the gelling temperature, gel-formation period, and overall st...

The intensity scattered by a network of cross~section-polydispersed cylinders in which the mesh size is far larger than the largest cross-sectional radius is calculated by considering a weight distribution function of the type w(r) +~ r~~ with two cut-off radii,

Sterile thermoreversibly gelling systems based on chitosan- glycerol phosphate were developed for intraperitoneal delivery of the antineoplastic agent 5-FU. The formulation was evaluated for gelling characteristics and in vitro drug release. Drug free gels were evaluated for in vitro cytotoxicity in L-929 mouse fibroblast cells. Drug loaded gels were subjected to acute toxicity studies in Swiss...

It is well-known that 3D in vitro cell cultures provide a much better model than 2D cell cultures for understanding the in vivo microenvironment of cells. However, significant technical challenges in handling and analyzing 3D cell cultures remain, which currently limits their widespread application. Herein, we demonstrate the application of wholly synthetic thermoresponsive block copolymer worm...

Emodin is a component in a Chinese herb, Rheum officinale Baill, traditionally used for diabetes and anticancer. Its poor solubility is one of the major challenges to pharmaceutical scientists. We previously reported on thermoreversible gel formulations based on poloxamer for the topical delivery of emodin. The present study was to understand the effect of poloxamer type on emodin solubility an...