A novel hydrogel bead [tannic acid (TA)–poly(vinyl alcohol) (PVA)/sodium alginate (SA)] with high strength prepared by biocompatible PVA, TA, and biocompatible SA via an instantaneous gelation method was applied to remove methylene blue (MB) from aqueous solution. The obtained TA–PVA/SA hydrogel beads were fully characterized by thermogravimetric analysis, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and so on. The adsorption performances of TA–PVA/SA hydrogel beads for MB were investigated by changing the factors of TA content, initial concentration, pH, adsorbent dosage, contact time, and temperature systematically. The maximum capacity of TA–PVA/SA hydrogel beads for MB removal was obtained to be 147.06 mg/g at 30 °C, whose capability was better than that without TA. After fitting the adsorbed data, it was basically consistent with the Langmuir isotherm and pseudo-second-order kinetic model. Thermodynamic studies indicated that MB removal was spontaneous and exothermic in nature. It is concluded that the low-cost TA–PVA/SA hydrogel beads as an easily recoverable adsorbent have a great potential on the removal of hazardous dyes from wastewater.

A novel magnetic adsorbent, poly(catechol‐1,4‐butanediamine)‐coated Fe3O4 composite (Fe3O4@PCBA), was successfully fabricated via an easy and gentle method according to the mussel‐inspired adhesion property of polydopamine. Effects of many factors on the adsorption performance of Fe3O4@PCBA for Cr(VI) were investigated, including temperature, pH value, contacting time, adsorbent dosage, and initial Cr(VI) concentration. The thermodynamics, adsorption isotherm, kinetics, and intraparticle diffusion of adsorption were also studied systematically. Results indicated that the removal rate of Cr(VI) was approximately close to 100% when the initial concentration was less than 120 mg/L, and the maximum uptake capacity of Fe3O4@PCBA for Cr(VI) was 280.11 mg/g complied with Langmuir isotherm model. Accordingly, the nocuous Cr(VI) could be partially reduced to Cr(III) during the adsorption period. Hopefully, this strategy could be extended to prepare series of magnetic Fe3O4@catechol–amine adsorbents with different amino and phenolic hydroxyl groups for Cr(VI) removal. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46530.

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Background: A recent patent has been issued for hydroxysafflor yellow A (HSYA) as a drug to prevent blood circulation disorders. Hydroxysafflor yellow B (HSYB), an isomer of HSYA with antioxidative effects, has been isolated from the florets of Carthamus tinctorius. The effects of HSYB on the proliferation of cancer cells and its mechanism of action have not been investigated. Objective: The aims of this study were to investigate the anti-cancer effects and the molecular mechanism of HSYB for breast cancer MCF-7 cells. Methods: MTT assays and colony formation assays were used to assess the survival and proliferation of MCF-7 cells, respectively. Hoechst 33258 and flow cytometry were used to measure cell apoptosis and flow cytometry to determine effects on the cell cycle. Western blots were used to measure protein levels. Results: Treatment with HSYB reduced survival and proliferation of human breast cancer MCF-7 cells in a dose-dependent manner. Furthermore, HSYB arrested the MCF-7 cell cycle at the S phase and downregulated cyclin D1, cyclin E, and CDK2. Compared with a control group, HSYB suppressed the protein levels of p-PI3K, PI3K, AKT, and p-AKT in MCF-7 cells. In addition, HSYB decreased the levels of Bcl- 2, increased the levels of Bax, cleaved caspase-3 and caspase-9, and subsequently induced MCF-7 cell apoptosis. Conclusion: These data demonstrate that HSYB arrests the MCF-7 cell cycle at the S phase and induces cell apoptosis. Patent US20170246228 indicates that HSYB can be potentially used for the prevention and treatment of human breast cancer.

Hydrogels bridged by some alcohol compounds are reported to be useful for high tough and antifreezing properties of electronics and energy storage devices. However, the relationship between the structures of the alcohols on the mechanical and antifreezing properties is not clear yet. For a better understanding of the relationship and influence mechanism, conjoined-network organohydrogels connected with three typical alcohols (ethylene glycol, glycerol, and sorbitol) as bridging molecules were constructed by utilizing a poly­(vinyl alcohol)/alginate-calcium (PVA/Alg-Ca) double-network hydrogel as a substrate. The results displayed that the organohydrogels exhibit high mechanical properties with a maximum at 2.4 MPa and good antifreezing performance with the lowest value at −61 °C. By further analyzing the mechanism by Fourier transform infrared spectroscopy (FTIR) and derivative thermogravimetry (DTG), it was observed that the hydrogen bonds among the bridging molecules, polymer chains, and water were considered to play a decisive role in the high performance of the organohydrogels. A high number of hydroxyl groups in the bridging molecules could be conducive to the better entanglement of polymer chains but less interaction with water. Nevertheless, under the synergistic effect of the hydrogen bonds and high-concentration free ions, the organohydrogels also delivered high ionic conductivity. Furthermore, an all-in-one flexible supercapacitor based on the organohydrogels was assembled. It delivered a superior areal specific capacitance of 140.75 mF cm–2 at 1.0 mA cm–2 and exhibited good flexibility and electrochemical stability under different bending conditions and a wide working temperature range (−20 to 60 °C). It could be promisingly applied in flexible energy storage devices working even in subzero environments.