Synthesis and proton conductivity of poly(styrene sulfonic acid)/heterocycle-based membranes

Database of Nonaqueous Proton-Conducting Materials

This work presents the assembly of 48 papers, representing 74 different compounds and blends, into a machine-readable database of nonaqueous proton-conducting materials. SMILES was used to encode the chemical structures of the molecules, and we tabulated the reported proton conductivity, proton diffusion coefficient, and material composition for a total of 3152 data points. The data spans a broad range of temperatures ranging from -70 to 260 °C. To explore this landscape of nonaqueous proton conductors, DFT was used to calculate the proton affinity of 18 unique proton carriers. The results were then compared to the activation energy derived from fitting experimental data to the Arrhenius equation. It was found that while the widely recognized positive correlation between the activation energy and proton affinity may hold among closely related molecules, this correlation does not necessarily apply across a broader range of molecules. This work serves as an example of the potential analyses that can be conducted using literature data combined with emerging research tools in computation and data science to address specific materials design problems.

Rapid, Highly-Efficient and Selective Removal of Anionic and Cationic Dyes from Wastewater Using Hollow Polyelectrolyte Microcapsules

Herein, poly (allylamine hydrochloride) (PAH)/ poly (styrene sulfonic acid) sodium salt (PSS) microcapsules of (PAH/PSS)2PAH (P2P MCs) and (PAH/PSS)2 (P2 MCs) were obtained by a layer-by-layer method. The P2 MCs show high adsorption capacity for Rhodamine B (642.26 mg/g) and methylene blue (909.25 mg/g), with an extremely low equilibrium adsorption time (~20 min). The P2P MCs exhibited high adsorption capacities of reactive orange K-G (ROKG) and direct yellow 5G (DY5G) which were 404.79 and 451.56 mg/g. Adsorption processes of all dyes onto microcapsules were best described by the Langmuir isotherm model and a pseudo-second-order kinetic model. In addition, the P2P MCs loaded with reactive dyes (P2P–ROKG), could further adsorb rhodamine B (RhB) dye, and P2 MCs that had adsorbed cationic MB dyes could also be used for secondary adsorption treatment of direct dye waste-water, respectively. The present work confirmed that P2P and P2 MCs were expected to become an excellent adsorbent in the water treatment industry.

Study on Doxorubicin Loading on Differently Functionalized Iron Oxide Nanoparticles: Implications for Controlled Drug-Delivery Application

Nanoplatforms applied for the loading of anticancer drugs is a cutting-edge approach for drug delivery to tumors and reduction of toxic effects on healthy cells. In this study, we describe the synthesis and compare the sorption properties of four types of potential doxorubicin-carriers, in which iron oxide nanoparticles (IONs) are functionalized with cationic (polyethylenimine, PEI), anionic (polystyrenesulfonate, PSS), and nonionic (dextran) polymers, as well as with porous carbon. The IONs are thoroughly characterized by X-ray diffraction, IR spectroscopy, high resolution TEM (HRTEM), SEM, magnetic susceptibility, and the zeta-potential measurements in the pH range of 3-10. The degree of doxorubicin loading at pH 7.4, as well as the degree of desorption at pH 5.0, distinctive to cancerous tumor environment, are measured. Particles modified with PEI were shown to exhibit the highest loading capacity, while the greatest release at pH 5 (up to 30%) occurs from the surface of magnetite decorated with PSS. Such a slow release of the drug would imply a prolonged tumor-inhibiting action on the affected tissue or organ. Assessment of the toxicity (using Neuro2A cell line) for PEI- and PSS-modified IONs showed no negative effect. In conclusion, the preliminary evaluation of the effects of IONs coated with PSS and PEI on the rate of blood clotting was carried out. The results obtained can be taken into account when developing new drug delivery platforms.

A poly(allylamine hydrochloride)/poly(styrene sulfonate) microcapsule-coated cotton fabric for stimulus-responsive textiles

This study reports the design of a stimulus-responsive fabric incorporating a combination of microcapsules, containing polyelectrolytes poly(allylamine hydrochloride) (PAH) and poly(styrene sulfonate) sodium salt (PSS), formed via a layer-by-layer (LBL) approach. The use of PAH and PSS ensured that the microcapsule structure was robust and pH-sensitive. SEM and TEM studies showed that the composite microcapsule (PAH/PSS) n PAH had a spherical morphology with a hollow structure. FTIR demonstrated the presence of PAH and PSS, confirming the composition of the microcapsule shell. DSC showed that the microcapsules were thermally stable. The size of the microcapsules ranged from 4 μm to 6 μm. The hollow microcapsules can be used as a carrier for loading and releasing chemicals under different pH conditions. The release rate of Rhodamine-B from (PAH/PSS) n PAH microcapsules was higher at pH 5.8 than that at 7.4, confirming the pH sensitivity. The hollow structure of (PAH/PSS) n PAH microcapsules is expected to act as a carrier and medium to introduce functional chemicals into the fabric with long-lasting property and pH stimulus responsivity. Furthermore, a positively charged compound with ethylene oxide groups was added during the coating process as a crosslinker binding (PAH/PSS)2PAH for the microcapsules with the cotton fabric more efficiently. Using this method, numerous substances, e.g., drugs, dyes, natural herbs, or perfumes, could be stored into the LBL microcapsules for a relatively long time, constantly releasing them from the coated textiles. Since LBL microcapsules were easy to combine with fabrics, this study provided a feasible approach for the preparation of functional stimulus-responsive textiles.