Poly(triphenyl-4-vinylbenzylphosphonium chloride) synthesized via RAFT polymerization exhibits both tunable halide ion- and thermo-responsiveness (UCST-type) in aqueous solution and acts as a thermosensitive stabilizer for carbon nanotubes.

Delivery of therapeutics to the intestinal region bypassing the harsh acidic environment of the stomach has long been a research focus. On the other hand, monitoring a system's pH during drug delivery is a crucial diagnosis factor as the activity and release rate of many therapeutics depend on it. This study answered both of these issues by fabricating a novel nanocomposite hydrogel for intestinal drug delivery and near-neutral pH sensing at the same time. Gelatin nanocomposites (GNCs) with varying concentrations of carbon dots (CDs) were fabricated through simple solvent casting methods. Here, CDs served a dual role and simultaneously acted as a cross-linker and chromophore, which reduced the usage of toxic cross-linkers. The proposed GNC hydrogel sample acted as an excellent pH sensor in the near-neutral pH range and could be useful for quantitative pH measurement. A model antibacterial drug (cefadroxil) was used for the in vitro drug release study at gastric pH (1.2) and intestinal pH (7.4) conditions. A moderate and sustained drug release profile was noticed at pH 7.4 in comparison to the acidic medium over a 24 h study. The drug release profile revealed that the pH of the release medium and the percentage of CDs cross-linking influenced the drug release rate. Release data were compared with different empirical equations for the evaluation of drug release kinetics and found good agreement with the Higuchi model. The antibacterial activity of cefadroxil was assessed by the broth microdilution method and found to be retained and not hindered by the drug entrapment procedure. The cell viability assay showed that all of the hydrogel samples, including the drug-loaded GNC hydrogel, offered acceptable cytocompatibility and nontoxicity. All of these observations illustrated that GNC hydrogel could act as an ideal pH-monitoring and oral drug delivery system in near-neutral pH at the same time.

The thermal phase behaviors of a series of newly designed 1-alkyl-3-methylimidazolium ionic liquids (ILs) of different chain length fatty acid carboxylate anions are investigated. The length of the alkyl chain of the carboxylate anion in IL influences the phase transition temperature of their crystalline solid phase and the mesophase stability. When the palmitate anion of the IL is replaced with palmitoyl ascorbate and palmitoyl-L-tryptophanate anions, its melting temperature decreases and eventually vanishes. The influence of structural modulation of ILs on their ionic conductivities is also studied. The interaction between the 1-alkyl-3-methylimidazolium cation and the fatty acid carboxylate anion is established by using ab initio based DFT calculations. The associated energies for single ion pair formation of these ILs are computed and are successfully correlated with the experimental findings, which finally leads to the most reasonable arrangement of the IL molecules in different phases.

Considering the great potential of layered transition-metal dichalcogenides in thin film photovoltaic, advanced composite materials, and biomedical applications, it is of high importance to have a highly efficient method for their generation in both aqueous and nonaqueous media. Here, we demonstrate a simple one-pot efficient exfoliation approach to prepare dispersion of single or few-layers MoS 2 nanosheets by quick sonication in the presence of cationic poly(ionic liquids)s (PILs) in both aqueous and nonaqueous media at room temperature. These PILs are synthesized by simple conventional free radical polymerization from designed ionic liquid monomers. This method is extendable for efficient generation of MoSe 2 nanosheets' dispersion in these solvents. Owing to the solubility in both water and organic solvents, cationic PIL molecules serve the dual purpose of an exfoliating-cum-stabilizing agent. PIL-stabilized nanosheets' dispersions are stable for more than two months at ambient temperature. The adsorption of PIL to the surface of MoS 2 nanosheet converts them to responsive toward ions and temperature in aqueous medium. Additionally, MoS 2 −PIL nanosheets can easily be dispersed in water-soluble poly(vinyl alcohol) and nonaqueous-soluble poly(methyl methacrylate) matrices for making well-dispersed homogeneous nanocomposites and their dielectric properties are studied.