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Oil pollution from the petroleum industry is a growing problem, especially in terms of the harm it causes to the aquatic environment, which puts humans and other aquatic life in grave danger. As immobilized carriers for the removal of diesel, thermoplastic polyurethane (TPU) nanofiber membranes and co-blended nano-hydroxyapatite modified thermoplastic polyurethane (TPU/nHA) nanofiber membranes are reasonably priced, non-toxic, and non-polluting. The adhesion and colonization of the bacterial cells to these carriers were studied using scanning electron microscopy (SEM). Gas chromatography was used to measure the bioremediation effectiveness, and the results after 3 days of remediation revealed a substantial improvement in the removal of hydrocarbons by immobilization compared to free bacteria. With an initial concentration of 3 g/L diesel, the TPU/1.5HA-bacteria system enhanced the removal of diesel the most (20.64 ± 0.40%), followed by TPU/1HA-bacteria (17.49 ± 0.08%), TPU/0.5HA-bacteria (11.97 ± 0.40%), and TPU-bacteria (4.69 ± 0.13%), in that order. Within three days, these scaffolders had completely absorbed the spilled diesel. There haven't been any studies done yet on the removal of diesel using various carriers loaded with Bacillus altitudinis LS-1. This study demonstrated that TPU-based electrostatic spinning films can be used as bio-carriers for hydrocarbon-degrading bacteria, enhancing the bioremediation of oil-contaminated water. [ABSTRACT FROM AUTHOR]

In this work, molecularly imprinted electrospun chromogenic membrane(MIP-ECM) was synthesized using P -Hydroxybenzene propanoic acid as imitate template molecule and Poly (vinyl alcohol)(PVA) as substrate. Ninhydrin is used as chromogenic agent for visualizing detection of target molecule l -tyrosine(Tyr). The results showed that molecularly imprinted membrane exhibited selectivity and specific adsorption capacity for l -tyrosine. The influences of environmental factors, such as reaction temperature, the amount of ninhydrin and elution time, on chromogenic properties were examined by SEM and optical microscope. Gray value analysis is proceeded by software Image J. Due to the facilitate preparation and intuitive visualization, the proposed method was a promising candidate for selective recognition of bio-generated acid and amino molecules. Image 1 • The imprinting and coloring structure is constructed in nanofiber membrane with large surface area. • The adsorption is visualized by chromogenic reaction to form a 3D interactive surface proceeded by ImageJ. • The test process is fast and not it is not necessary to sample the subject for UV spectrum absorption. [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]

Protein-imprinted polyacrylamide (PAM)-grafted calcium alginate (CaA) microspheres were synthesized via free-radical grafting polymerization with potassium persulfate and sodium bisulfite as initiators. FTIR, 13C-NMR and SEM were used for characterization. Swelling behaviors were studied and it was found that modified calcium alginate (CaA) microspheres possessed larger swelling degree than calcium alginate, because grafted hydrophilic PAM side chains contributed to more water absorption. Moreover, the durability of the swollen samples was improved for the modified microspheres. Compared with calcium alginate microspheres, modified calcium alginate samples exhibited higher absorption capacity (approximately, 13.1 and 10.3 mg/g) for MIPs in single and binary protein solution. The rebinding selectivity of CaA-g-PAM microspheres (approximately, 2.7) was higher than that of calcium alginate (CaA) microspheres (approximately, 1.5) in binary protein solution. It was suggested that the introduction of PAM side chains was beneficial for the specific recognition of protein. [ABSTRACT FROM AUTHOR]

This work is an exploration into visualizing measurement of putrescine specific adsorption by photographing colorized molecule imprinting chromogenic hydrogel. Membranes are prepared with imitate templates 1,4-butylene glycol, adipic acid or succinic acid, respectively and ninhydrin is used as chromogenic agent for target molecule putrescine. The adsorbing concentration on MIP is reflected in the form of visible violet-colored stain differed in shape and shade, which are recorded by hyper spectral camera and proceeded into intuitive 3D isohypse surfaces plot. By quantifying the height of surface peaks, imprinting efficiency is estimated in accordance with polyvinyl alcohol concentration and crosslinking degree. The imprinting efficiency of three imitate molecule templates is also discussed. [ABSTRACT FROM AUTHOR]

Bovine serum albumin imprinted polyethylene glycol 600 (PEG600) grafted Calcium alginate (CaA) hydrogel microspheres were prepared and characterized. The adsorption and recognition properties of PEG600 grafted calcium alginate (CaA- g-PEG600) microspheres were evaluated and the results showed that the crosslinking structure of CaA- g-PEG600 microspheres exerted an obvious effect on the adsorption capacity and imprinting properties for bovine serum albumin. The adsorption isotherms and recognition properties indicated that the imprinted modified microspheres had excellent rebinding affinity toward target proteins and the imprinting efficiency varied according to PEG600 grafting degree. The adsorption capacity and the imprinting factor were 5.5 mg g and 3.6, respectively. Adsorption kinetics of CaA- g-PEG600 microspheres in accordance with the molecular weight between crosslinks ( Mc) was investigated and the structural influence on protein selective rebinding was discussed. Furthermore, the binary solution separation performance of CaA- g-PEG600 microspheres with different Mc was investigated by selective binding bovine serum albumin from protein mixture solution. [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]

Polyurethane grafted calcium alginate hydrogel microspheres intended for bovine serum albumin imprinting were prepared and characterized. The grafting modification was performed prior to the assembling of protein template with hydrogel, which was advantageous to maintain protein conformation and construct more accessible imprinted sites. It was found that the imprinted hydrogel had higher affinity to template molecules after modification. Investigations of grafting ratio influence on specific rebinding and competitive properties indicated that grafted side chains were beneficial to the selective recognition of protein. [ABSTRACT FROM AUTHOR]

Abstract: Polyurethane was synthesized by the reaction of isophorone diisocyanate, 2-hydroxyethyl methacrylate and diethylene glycol. Then polyurethane grafted calcium alginate gel material was prepared via free-radical grafting polymerization with azobisisobutyronitrile as an initiator. Modified calcium alginate hydrogel was improved in thermal property, crystallinity and anti-swelling properties. The reason is that polyurethane side chains affect the arrangement of calcium alginate by forming highly ordered crystal region. [Copyright &y& Elsevier]

Agarose hydrogel microspheres imprinted with bovine serum albumin (BSA) were prepared by inverse suspension gelating method. The experimental conditions related with beads’ shape and uniformity were studied, including temperature, surfactant content, and stirring speed. The size and distribution of the pores were found related with porogen and surfactant content. Rebinding properties were influenced by the diameter and porosity. The beads with the smallest diameter exhibited the greatest rebinding capacity, rebinding speed, and imprinting efficiency (IE). Smaller pores provided higher rebinding capacity and IE, but lower rebinding speed. Imprinted microspheres showed good specificity toward templating protein compared to others. [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]

Abstract: With the aim of improving the performance of calcium alginate (Ca-Alg) hydrogel, a small quantity (5% of dry mass of sodium alginate) of hydroxyethyl cellulose (HEC) was used to associate sodium alginate to form interpenetrating networks (IPNs). Swelling results and mechanical stability tests showed that the formation of IPNs considerably restrained dried samples from swelling in 0.9% sodium chloride aqueous solution and reinforced the mechanical strength of microspheres. For emulsion droplets as template, microscopy showed that the original emulsion templating method employed in preparation of macroporous Ca-Alg microspheres was also applicable in the IPNs system. As for bovine serum albumin molecules as template, Alg/HEC microspheres showed a better recognition effect than that of Ca-Alg microspheres. The reduced network mesh size and strengthened cross-linkages in IPNs are responsible for these results. [Copyright &y& Elsevier]

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]

Sodium lignosulfonate amine (SLA) was synthesized by Mannich reaction. The lignin-modified waterborne polyurethane (WPU) with different branched structures was designed and prepared by introducing SLA as a hydrophilic chain extender. The effect of the introduction manner of SLA on the performance of WPU was systematically investigated. The results showed that the addition of 0.75 wt% SLA in an appropriate introduction manner can prepare a polyurethane dispersion with good stability and high solid content. The tensile strength of the SLA-modified WPU film was significantly improved to 37.3 MPa. The SLA-modified WPU film also exhibited high water resistance and thermal stability. Moreover, in the introduction manner of WPU-C, the adhesive properties of SLA-modified WPU adhesives were also improved, which was mainly attributed to the entanglement of long branched chains generated by SLA chain extension with other polyurethane chains and the formation of physically cross-linked networks through the interaction between functional groups. Therefore, the introduction of a small amount of sodium lignosulfonate amine in an appropriate manner can significantly improve the performance of WPU with high solid content, which provides a new way to prepare high-performance waterborne polyurethane. [Display omitted] • Sodium lignosulfonate amine optimized the structure of waterborne polyurethane. • A small amount of sodium lignosulfonate amine improved the properties of WPU. • Provide a new idea for preparation of high-performance WPU. • Expand the way for high-value utilization of sodium lignosulfonate. [ABSTRACT FROM AUTHOR]

An electrochemical sensor for L-tryptophan based on a molecularly imprinted polymer was developed. The sensing film was prepared by the co-electropolymerization of o-phenylenediamine and hydroquinone on a gold electrode in the presence of L-tryptophan as the template. The performance of the L-tryptophan sensor was characterized by cyclic voltammetry, differential pulse voltammetry, and alternating current impedance. Under the optimal experimental conditions, the relative current change was linear to the concentration of L-tryptophan in the range of 1.0 × 10−8to 1.0 × 10−6 mol/L and a detection limit of 0.50 × 10−8 mol/L was obtained. The sensor showed high sensitivity and selectivity for L-tryptophan. The imprinting factor was 3.58 and selectivity factors of L-tryptophan compared to analogs were larger than 2. The sensor also demonstrated good resistance to acidic, basic, and organic environments. [ABSTRACT FROM AUTHOR]

An electrochemical sensor for L-tryptophan based on a molecularly imprinted polymer was developed. The sensing film was prepared by the co-electropolymerization of o-phenylenediamine and hydroquinone on a gold electrode in the presence of L-tryptophan as the template. The performance of the L-tryptophan sensor was characterized by cyclic voltammetry, differential pulse voltammetry, and alternating current impedance. Under the optimal experimental conditions, the relative current change was linear to the concentration of L-tryptophan in the range of 1.0 × 10−8to 1.0 × 10−6 mol/L and a detection limit of 0.50 × 10−8 mol/L was obtained. The sensor showed high sensitivity and selectivity for L-tryptophan. The imprinting factor was 3.58 and selectivity factors of L-tryptophan compared to analogs were larger than 2. The sensor also demonstrated good resistance to acidic, basic, and organic environments. [ABSTRACT FROM AUTHOR]

Abstract: Calcium phosphate/alginate hybrid polymer microspheres with bovine serum albumin (BSA) embedded and coated on the surface were prepared with sodium alginate (SA) and (NH4)2HPO4 by using CaCl2 as the gelling agent in an inverse suspension. The morphology and pore structure of imprinted hybrid polymer microspheres was observed by optical microscopy, ESEM, TEM and SEM. Infrared spectrum analysis demonstrated that new hybrid components were produced in the polymer microspheres. Rebinding dynamic and thermodynamic behaviors of the two imprinted microspheres were evaluated, resulting in a higher BSA affinity for imprinted microspheres relative to non-imprinted ones. The factors influencing the imprinting efficiency (IE) of imprinted microspheres were also studied, including the concentration of CaCl2, template content and pH in rebinding solution, etc. All the results indicated that the surface imprinted microspheres exhibited better imprinting efficiency and higher rebinding capacity. Selectivity tests showed that the imprinted beads exhibited good recognition properties for the template protein versus others. [Copyright &y& Elsevier]

• The superhydrophobic BSSS is fabricated by mimicking the stomata effect of leaves. • A facile swelling-vesiculating-cracking method is developed. • The BSSS is provided with wonderful durability in different solvents. • A theoretical model for BSSS is established to elucidate the stomata effect. Fabrication of superhydrophobic surfaces by simple techniques is of significant interest. Herein, inspired by the "stomata effect" of plant leaves, a superhydrophobic surface with bionic stomata randomly on polydimethylsiloxane (PDMS) is fabricated by a facile swelling-vesiculating-cracking method. Neither multistep modification of nanostructure nor introduction of low surface energy substance is carried out during the fabrication. The water contact angle (CA) of the bio-inspired superhydrophobic surfaces with stomata-like structures (BSSS) can reach 168.4 ± 1° with 8.9° sliding angle and less than 10° contact angle hysteresis (CAH). The structure and wettability of the BSSS are characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, energy dispersive spectrometry and X-ray photoelectron spectroscopy. The effects of swelling ratio, heat treatment temperature and surface morphology on the hydrophobicity of the BSSS are investigated systematically. Noticeably, the BSSS are provided with wonderful durability in organic solvents, ice water, and strong acid solution. Furthermore, a theoretical model for BSSS based on the Cassie-Baxter relation is established to elucidate the "stomata effect". The model reveals that the water contact angle will reach 180° when the stomata-like structure is suitable. The fabrication of BSSS provides a potential strategy for the development of novel superhydrophobic materials. [ABSTRACT FROM AUTHOR]