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Combining molecular imprinting technology with electrostatic spinning technology, a molecularly imprinted nanofiber membrane material with memory and recognition of specific imprinted molecules is thus produced. It has the advantages of high efficiency, reusability, easy amplification, and simple operation. In this study, alkane molecularly imprinted nanofibrous membranes are prepared as a carrier for immobilize Bacillus cereus LY‐1 for the degradation of diesel in oil–water system. The adsorption capacity of the molecularly imprinted material for diesel oil with n‐decyl alcohol as the template molecule reach 120.25 mg g−1, the adsorption capacity of alkane molecularly imprint nanofiber membrane prepared using polyvinyl alcohol (PVA) as the membrane substrate material is 41.37 mg g−1. After 4 days, the immobilized LY‐1 cells eliminate roughly 80.7% of the diesel at a starting concentration of 3 g L−1. The results show that imprinted structures in MINM enhance degradation by loaded microorganisms. [ABSTRACT FROM AUTHOR]

An imprinted electrospun fiber membrane was developed for the detection of volatile organic acids, which are key components of human body odor. In this study, hexanoic acid (HA) was selected as the target, polymethyl methacrylate (PMMA) was used as the substrate, and colorimetric detection of HA was achieved by a bromocresol purple (BCP) chromogenic agent. The results showed that the morphology of the fiber membrane was uniform and continuous, and it showed excellent selectivity and specificity to HA. Photographs of the color changes before and after fiber membrane adsorption were recorded by a camera and quantified by ImageJ software by the difference in gray value (ΔGray). This method is simple, intuitive, and low cost and has great potential for application in human odor analysis.

Microbial fuel cells (MFCs) are a potential biotechnology for simultaneous degradation of organic wastewater and power generation. In this paper, a biocompatible composite is constructed around a copper mesh with sodium alginate/agar and activated carbon (CM‐SA/AC) and acts as an efficient anode for MFCs after being microbe immobilized. The power performance of the MFC with CM‐SA/AC anode is investigated. The results show that the addition of activated carbon is conducive to the immobilization of bacteria on CM‐SA/AC anode and fast start‐up of MFCs. The power density reaches 1088.6 mW/m2, which is 2.03 times and 1.75 times that of CM‐SA (without activated carbon) anode and carbon felt anode, respectively. In case of a candied wastewater treatment, the MFC with immobilized CM‐SA/AC anode exhibits a much higher power density (724.5 mW/m2) than that with carbon felt anode (145.0 mW/m2), together with a longer stabilization time and a smaller charge‐transfer resistance. The total removal rate of chemical oxygen demand (COD) reaches 79.4 ± 0.65%. The present study will facilitate the development of inexpensive and biocompatible anodes to facilitate the application of MFCs in wastewater treatment. [ABSTRACT FROM AUTHOR]

As the core component of wearable electronic devices, flexible energy storage materials play an irreplaceable role. At present, it is still a challenge to prepare flexible electrode materials with high energy density. In this paper, a polyaniline‐based composite flexible conductive hydrogel (PPG‐P) with a two‐level conductive network is successfully prepared by a secondary induced assembly in situ polymerization method. The special conductive structure greatly promotes the efficiency of charge transfer and the utilization of electroactive substances, so that PPG‐P exhibits excellent electrochemical performance. In a three‐electrode system, PPG‐P has a mass‐specific capacitance as high as 989 F g−1 (0.5 A g−1). After 1000 charge and discharge cycles, the capacitance retention is 87%. Symmetrical flexible supercapacitors based on PPG‐P have high specific capacitance (176 F g−1/0.5 A g−1) and high energy density (15.6 Wh kg−1). After 1000 cycles of constant current charge and discharge, the capacitance maintains 78.1%. The preparation of PPG‐P with a hierarchical structure demonstrates the possibility of achieving high energy density in flexible electrode materials, which has great application potential in the development of energy storage elements in wearable devices. [ABSTRACT FROM AUTHOR]

In this work, we have developed a double‐layer nanofiber membrane (NFM) with high selectivity based on molecular imprinting technique by electrospinning methods and applied it in recognizing putrescine. Poly(vinyl alcohol) (PVA) was used as spinning solution, 1,4‐butylene glycol as the imitate template, and ninhydrin as chromogenic agent. The adsorption of the putrescine is corresponded to purple‐color stains on the NFM, which is digitizing intuitively by the ImageJ software. By quantifying the gray value of the stains on the NFM, its imprinting efficiency (IE) is estimated. The adsorption performance of the double‐layer molecular imprinted NFM was studied in detail, showing higher adsorption capacity (71.912 mg mL−1), shorter adsorption equilibrium time of 40 min and higher selectivity to putrescine than our previous works. Furthermore, the material showed remarkable selectivity for putrescine with respect to other three kinds of aliphatic amine in similar molecular structure. The selectivity coefficient (α) of putrescine against cadaverine, spermine, and spermidine are calculated to be 1.734, 2.224, and 2.576, respectively. In addition, since PVA is a water‐soluble material, the NFM is not reusable. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48932. [ABSTRACT FROM AUTHOR]

With the development of alternatives to traditional fossil energy and the rise of wearable technology, flexible energy storage devices have attracted great attention. In this paper, a polyaniline/poly(acrylamide‐sodium acrylate copolymer) hydrogel (PASH) with high flexibility and excellent electrochemical properties for flexible electrodes is fabricated by freeze‐thaw‐shrink treatment of a highly water‐absorptive hydrogel, together with in‐situ polymerization of aniline at a low aniline concentration (0.1 mol L−1). The PASH exhibits a conductivity of 4.05 S m−1 and an elongation at break of 1245%. The freeze‐thaw‐shrink treatment greatly improves the electrochemical performance and stability of the conductive PASH. The area specific capacitance of PASH reaches 849 mF cm−2 and the capacitance maintains 89% after 1000 galvanostatic charge–discharge cycles. All the raw materials are conventional industrialized materials and no additional templating agent is needed during the entire synthesis process. This study provides a cost‐efficient approach for the fabrication of conductive polymer hydrogels, which has a broad application prospect in flexible energy storage electronic devices. [ABSTRACT FROM AUTHOR]

Abstract Bovine serum albumin (BSA) imprinted polyampholyte hydrogels (PAHs) were prepared by free radical polymerization using acrylamide (Am) as structural monomer, N -isopropylacrylamide (NIPAm), [2-(methacryloyloxy)ethyl]trimethylammonium chloride (DMC) and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) as functional monomers and N , N′ -methylenebisacrylamide (MBA) as crosslinker in aqueous solution. The morphology of imprinted hydrogels and non-imprinted hydrogels were characterized by scanning electron microscope (SEM). The adsorption and recognition properties were evaluated as functions of Am monomer concentration, NIPAm/Am molar ratio, crosslinking structure and charge density ratio etc. The adsorption capacity and association constant of specific interaction between hydrogel and template protein were analyzed by Langmuir isotherm model and Freundlich model. The fitting experimental data suggested that this adsorption was better described as a monolayer adsorption. The specific adsorption on hydrogel with different crosslinking structure was investigated by selective binding BSA from single solution and binary mixture solution. The charge density ratio in molecular imprinting hydrogel had obvious influence for protein adsorption and recognition. The resultant of regeneration tests showed that elution had large impact on deterioration of the imprinting structure. Graphical abstract fx1 Highlights • Reversible electrostatic binding sites with high specificity have been constructed. • Polymerized electrical charge minimizes non-specific adsorption. • High imprinting efficiency is acquired in polyampholyte MIP hydrogels. [ABSTRACT FROM AUTHOR]

ABSTRACT Polyethylene glycol grafted calcium alginate hydrogel microspheres are synthesized by ring-opening and addition reaction of epoxy chloropropane. FTIR, 13C NMR, optical microscope, SEM, TG, and DSC are used for characterization. Swelling behaviors are studied and it is found that polyethylene glycol grafted calcium alginate microspheres are improved in anti-swelling properties. Protein-imprinted polyethylene glycol grafted calcium alginate hydrogel microspheres exhibit enhanced specific rebinding quantity (11.16 mg/g) and selective recognition properties (4.71 against BHb), towards target molecule in the presence of competing protein, compared with that of the unmodified samples (4.96 mg/g and 1.75, respectively). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43617. [ABSTRACT FROM AUTHOR]

Vinyl group capped urethane acrylate (UA) was prepared with diisocyanate (IPDI), hydroxyethyl methacrylate (HEMA) and dimethylolpropionic acid (DMPA). The UA was grafted onto sodium alginate via free-radical polymerization with KPS/Na 2 SO 3 as initiator and then crosslinked by Ca 2+ . Grafted polymers (UA- g- CaA) were characterized by FT-IR, SEM, TGA, XRD and tension gauge. The swelling behavior was also investigated. It is found that urethane acrylate grafted calcium alginate possesses lower swelling degree and is improved in thermal stability as well as mechanical performance. The reason is that hydrophobic urethane acrylate provides alginate with physical crosslinking and forms partial crystal regions. The optimum condition for synthesis of UA- g- CaA with lower swelling degree is that weight percentage of initiator to monomer is 0.8%, mass ratio of reductant to oxidant is 0.45:1, monomer concentration is 0.0385 mol/L and grafting reaction temperature is 55 °C. [ABSTRACT FROM AUTHOR]

ABSTRACT Protein-imprinted polyurethane-grafted calcium alginate hydrogel microspheres were prepared and characterized. The samples were investigated with optical microscopy, scanning electron microscopy, 13C-NMR, and Fourier transform infrared spectroscopy. We proved that polyurethane side chains were successfully grafted, and this led to a relatively rough and dense surface. The samples exhibited better swelling durability when applied in specific adsorption tests. The adsorption kinetic and recognition properties indicated that the imprinted modified microspheres had excellent rebinding affinity toward the target proteins. Moreover, the influence of the preassembly pH, rebinding pH, and grafting ratio on the adsorption capacity and imprinting efficiency (IE) were systematically investigated. The study results suggest that the modified samples possessed a higher IE toward the target protein under the optimum pH and grafting ratio. Upon polyurethane grafting modification, the alginate hydrogel microspheres showed improved mechanical stability and recognition specificity. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42140. [ABSTRACT FROM AUTHOR]

Electrospinning is an important tool for generating continuous fibers with large surface area and high pore ratio. The combination of nanofiber membrane and molecular imprinting can effectively measure specific adsorption of putrescine with coloring procedure. In this work, molecularly imprinted electrospun chromogenic membrane was synthesized with 1,4‐butanediol (BDO) as imitate template. Poly(vinyl alcohol) (PVA) is used as spinning solution and ninhydrin as chromogenic agent for visualizing detection of target molecular putrescine. The adsorption concentration on molecularly imprinted polymer is illustrated by blue‐purple colored stains and recorded by interactive three‐dimensional surface plot of ImageJ. The results indicated that a uniform and bead‐free PVA nanofiber was obtained using 10% (w/w) PVA solution, 15 kV voltage, 15 cm spinning distance, and 600 rpm roller speed. Also, the adsorption performance of molecular imprinting chromogenic membrane was investigated in detail, showing a higher adsorption capacity of 33.16 μg cm−2 and maximum imprinting efficiency of 2.30 under the best recognition conditions of 315 μL ninhydrin, 0.25% (w/w) BDO, and 0.4 cm sensing distance, as well as a short adsorption equilibrium time of 40 min. In addition, three amine competitors were discussed to reveal the better selectivity and higher specific recognition ability in the imprinted membrane. HIGHLIGHTS: The molecular imprinting and coloring structure is constructed in nanofiber membrane with an enhanced specific surface area.The adsorption on imprinted membrane is visualized by chromogenic reaction between putrescine and ninhydrin to form a three‐dimensional interactive surface proceeded using the ImageJ software.The imprinted nanofiber membrane with large area and high pore ratio is applied in detecting target in trace concentration within shortened time. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48186. [ABSTRACT FROM AUTHOR]

A strain of Lysinibacillus sp . , named as Y316, can degrade heavy fractions such as resins and asphaltenes in oil sand. We used Y316 to degrade oil sand samples for 35 days. After bacterial degradation, the oil sand degradation efficiency was 5.88%, while the degradation efficiency of the control group was only 0.29% under the same conditions. Compared with the control group, the saturated content of oil sand in the degradation group increased from 9.56 to 14.39%. After degradation, the resin and asphaltene fractions decreased by 5.34 and 4.77%, respectively. The results of the vaporizable fraction analysis also confirmed the degradation of heavy fractions and the formation of light fractions. After 35 days of degradation, the vaporizable fractions of saturates increased by 3.76 times. The results indicate that Y316 has great significance for improving the quality of oil sands and assisting in oil sand exploitation., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)