Hexaphyrin as a Potential Theranostic Dye for Photothermal Therapy and 19F Magnetic Resonance Imaging

Two features of meso‐Aryl‐substituted expanded porphyrins suggest suitability as theranostic agents. They have excellent absorption in near infrared (NIR) region, and they offer the possibility of introduction of multiple fluorine atoms at structurally equivalent positions. Here, hexaphyrin (hexa) was synthesized from 2,6‐bis(trifluoromethyl)‐4‐formyl benzoate and pyrrole and evaluated as a novel expanded porphyrin with the above features. Under NIR illumination hexa showed intense photothermal and weak photodynamic effects, which were most likely due to its low excited states, close to singlet oxygen. The sustained photothermal effect caused ablation of cancer cells more effectively than the photodynamic effect of indocyanine green (a clinical dye). In addition, hexa showed potential for use in the visualization of tumors by ¹⁹F magnetic resonance imaging (MRI), because of the multiple fluorine atoms. Our results strongly support the utility of expanded porphyrins as theranostic agents in both photothermal therapy and ¹⁹F MRI.     

Photo‐induced grafting of poly(ethylene glycol) onto polyamide thin film composite membranes

In this study, the surface grafting of poly(ethylene glycol) (PEG) onto commercial polyamide thin film composite (TFC‐PA) membranes was carried out, using ultraviolet photo‐induced graft polymerization method. The attenuated total reflection Fourier transform infrared spectra verify a successful grafting of PEG onto the TFC‐PA membrane surface. The scanning electron microscope and atomic force microscope analyses demonstrate the changes of the membrane surface morphology due to the formation of the PEG‐grafted layer on the top. The contact angle measurements illustrate the increased hydrophilicity of the TFC‐PA‐g‐PEG membrane surfaces, with a significantly reduced water contact angles compared to the unmodified one. Consequently, the separation performance of the PEG‐grafted membranes is highly improved, with a significant enhancement of flux at a great retention for removal of the different objects in aqueous feed solutions. In addition, the antifouling property of the modified membranes is also clearly improved, with the higher maintained flux ratios and the lower irreversible fouling factors compared to the unmodified membrane. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45454.     

Enhanced Reaction Efficiency in Continuous Flow

Continuous flow reactors are enabling tools that can significantly benefit chemical reactions, especially those that are path length dependent (e.g., photochemical), mixing or transport dependent (e.g., gas-liquid), exothermic, or utilize hazardous or unstable intermediates. In this review, it is demonstrated how the nearly instantaneous mixing, exceptionally fast mass transfer, safe access to high temperatures and pressures, and high surface area to volume ratio can be leveraged to improve product yield, reaction rates and/or selectivity. By showcasing five synthetic methodologies examined by our group, it is hoped that the reader will gain an appreciation of the accessible and transformative nature of flow chemistry for improving existing transformations, enabling rapid optimization, and for developing new methodologies that depend on precise parameter controls.     

Investigation of inter‐relationship between tensile behavior and photocatalytic activity of an acrylic‐based composite upon UVA exposure

The aim of this work is to produce a photocatalytic pseudo‐paint for benzene removal from air and find the role of TiO₂ nanoparticles, TiO₂ pigment, and CaCO₃ extender on photocatalytic performance of this paint along with their role on stress–strain behavior after ultraviolet (UV) exposure. For this purpose, TiO₂ nanoparticles were dispersed into an indoor paint resin (i.e., copolymer acrylic–styrene). The impact of main components of the paint on photocatalytic oxidation (PCO) rate of benzene was studied. It was found that dispersion of nanoparticles had the most dramatic effect on photo activity of nanocomposite. TiO₂ pigment generally increased PCO rate and also made the paint more stable under tensile stress. CaCO₃ may increase and/or decrease PCO of benzene, whether there is pigment in the formulation or not. However, it does not generally contribute to making the formulation resistant to UV exposure. Nanoparticles bring PCO and mechanical strength into the paint, but fail to strengthen the composite against UV deterioration. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44447.     

Suwannee河腐植酸光化学生成溶解无机碳的研究

溶解有机质矿化为溶解无机碳是全球碳循环中的一个重要过程.利用模拟太阳光对Suwannee河腐植酸的光氧化过程模拟,研究了溶解氧浓度、模拟太阳光波长范围和铁浓度对溶解无机碳产量的影响.研究表明,基于前24 h空气饱和的无机碳矿化速率4.40μmol/(L.h),氧气饱和条件下照射增加1.56倍,氮气饱和条件下照射下降36%.UV-B,UV-A和可见光部分分别占溶解无机碳产量的31.8%、32.6%和25.6%.当加入20μmol/L铁络合剂DFOM时(初始样品Suwannee河腐植酸铁含量为5.46μmol/L),溶解无机碳产量下降55.6%.     

A new modified silicone–TiO2 polymer composite film and its photocatalytic degradation

The photodegradation of the silicone surfactant–TiO₂ composite films was characterized by FTIR, Raman spectroscopy, and scanning electron microscope. After photocatalytic degradation, the FTIR Si? O? Si peak intensity of the composite film remained unchanged, implying no cleavage of Si? O? Si bond. The above Si? O? Si peak intensity is sensitive to the polyoxyethylene chain length of the composite. The PEG10000‐silicone composite is more resistant to photodegradation than those composites with lower molecular weight of constituent PEGs. The wetting rates of the silicone surfactant–TiO₂ composites showed that modified silicone composite films exhibited hydrophobic nature. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3341–3344, 2006     

Nanoscale surface roughening of mulberry silk by monochromatic VUV excimer lamp

Surface treatment of mulberry silk was carried out using a VUV excimer lamp (172 nm). The changes occurring in morphology and physical properties of silk were studied. The nanopores created on the surface of treated samples were quantitatively analyzed using a high resolution scanning electron microscope. The physical and chemical changes taking place in silk fabric on irradiation were studied through measurement of wetting and wicking time, weight loss, crystallinity, and strength. Effect of irradiation time and distance from the lamp on these properties was also studied. Results show that wettability and wickability of silk improved significantly on exposure before stabilizing at 5 min irradiation time while the weight loss continued to increase. The effect of irradiation was negligible when the distance of the sample from the lamp became >15 mm. The effect of irradiation on tensile strength was found to be insignificant. Presence of moisture in silk hindered the effect of irradiation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 4102–4106, 2007     

Photoelectrochemical water splitting into active hydrogen/oxygen species coupling with hydrogenation/oxidation process using layered double hydroxides-based nanocatalysts

Hydrogenation/oxidation processes are regarded as the most widely used catalytic reactions in modern chemical development. However, the traditional reaction process always requires harsh reaction conditions (such as high temperature, high pressure, a lot of hydrogen/oxygen consumption, etc), the high cost, overconsumption of energy and low selectivity is always limiting its further development. Therefore, conducting the hydrogenation/oxidation reaction efficiently under mild conditions is one of the greatest challenges in this field. Photoelectrocatalysis has been widely studied due to its wide, clean and sustainable energy sources, which combines the advantages of both photocatalysis and electrocatalysis. Moreover, the process of generating H₂/O₂ by photoelectrocatalytic water splitting involves the production of highly reactive intermediate species (active hydrogen *H and active oxygen *O) which can be used by directly coupling the hydrogenation/oxidation catalytic processes, and the efficiency of coupled reaction will be greatly improved. The review here summarizes the research progress of photoelectrocatalysis from three aspects: active species of intermediate products produced by photoelectrochemical water splitting, hydrogenation/oxidation reaction of the traditional chemical industry, and coupling photoelectrochemical water splitting with hydrogenation/oxidation process using layered double hydroxides (LDHs)-based nanomaterials. It is expected to provide ideas for the high selectivity and low cost preparation of high value-added organic chemicals.     

光化学AOPs去除水中抗生素抗性菌和抗性基因研究进展

抗生素的滥用所导致的细菌耐药性增强以及抗性基因污染问题,对人类健康和生态安全造成了极大的威胁,如何高效地去除水中抗生素抗性菌(简称ARB)和和抗生素抗性基因(简称ARGs)成为当前研究重点.光化学高级氧化技术(简称AOPs)可以利用光辐照产生具有强氧化性的活性氧物种来氧化分解水中难降解有机污染物,对于水中抗性菌和抗性基因的去除具有广阔的应用前景.该文首先介绍了抗生素抗性基因传播扩散机制及污染现状,其次对光化学AOPs应用于去除水中抗生素ARB和ARGs的研究进展进行归纳,并分析了影响去除效果的因素及其应用的局限性,最后指出未来应加强对于光化学AOPs灭活的氧化损伤机制以及与规模化实际工程应用相结合的研究.     

Controlled Swelling of Poly(hydroxyethyl methacrylate) Hydrogels by Photochemical Grafting of Hydrophobic Acrylates

The photochemically induced grafting polymerization of various alkyl acrylates onto cross‐linked poly(hydroxyethyl methacrylate) (PHEMA) was performed to reduce the hydrophilicity of the swellable network. Butyl, 2‐ethylhexyl and lauryl acrylate were used as monofunctional monomers for increasing the hydrophobic character, whereas hexanediol diacrylate was used as a multifunctional monomer with the additional feature of forming networks. The various steps of the grafting procedure were examined sequentially so as to optimize the overall hydrophobing effect. The grafting yield was shown to depend primarily of PHEMA swelling in the considered ethanol/monomer mixture. In spite of their high specific hydrophobic character, alkyl monoacrylates were shown to be less efficient because of lower grafting yield. Grafting initiation by hydrogen abstraction with benzophenone or by homolytic cleavage of a hydroxyalkyl‐phenone resulted in comparable grafting yields even with monofunctional monomers. The hardness measured for the water swollen rubbery materials correlated well to the equilibrium water content.

Shore A hardness as a function of the swelling ratio in water at T = 22 °C for grafted and ungrafted PHEMA hydrogels (same samples as those described in Table 5 ).