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Mycoplasma contamination in cell/tissue cultures significantly affects cell characteristics, susceptibility to infectious pathogens, and drug reactions without obvious morphological changes and noticeable changes in cell growth rates. Although the technology for screening mycoplasma is essential, conventional technologies have limitations in the selection of a quick and easy manner. Here, we introduce an innovative screening system for mycoplasma based on electrochemical methods. In the electrochemical screening, a newly designed electrode, consisting of a sandwich-DNA hybridization for high selectivity and a nano-amplifier to improve the sensitivity, has implemented a realistic screening system by presenting detection capability at extremely low (ng/μL) levels and detection potential in real samples. Therefore, this system offers rapid screening, data accuracy, temporal effectiveness, and affordable-and-portable installation, enabling timely elimination of Mycoplasma contamination and facilitating progress in biomedical and pharmaceutical research.

Cancer patients are increasing in number, with an increased lifespan and advances in cancer treatment. Palliative care physicians often encounter difficulties in caring for patients with pain. In addition to cancer-related pain, patients with cancer may suffer from various musculoskeletal diseases, resulting in significant functional limitations of physical activities of daily living. We present three cases illustrating methods to deal with nonspecific mechanical low-back pain in patients with advanced cancer. We provide our therapeutic experiences, focusing on the usefulness of radiofrequency treatment in palliative care in patients with cancer.

Lithium–sulphur batteries (LiSBs) have garnered significant attention as the next-generation energy storage device because of their high theoretical energy density, low cost, and environmental friendliness. However, the undesirable “shuttle effect” by lithium polysulphides (LPSs) severely inhibits their practical application. To alleviate the shuttle effect, conductive polymers have been used to fabricate LiSBs owing to their improved electrically conducting pathways, flexible mechanical properties, and high affinity to LPSs, which allow the shuttle effect to be controlled. In this study, the applications of various conductive polymers prepared via the simple yet sophisticated electropolymerisation (EP) technology are systematically investigated based on the main components of LiSBs (cathodes, anodes, separators, and electrolytes). Finally, the potential application of EP technology in next-generation batteries is comprehensively discussed.

Abstract Li–S batteries have attracted considerable interest as next-generation energy storage devices owing to high energy density and the natural abundance of sulfur. However, the practical applications of Li–S batteries are hampered by the shuttle effect of soluble lithium polysulfides (LPS), which results in low cycle stability. Herein, a functional interlayer has been developed to efficiently regulate the LPS and enhance the sulfur utilization using hierarchical nanostructure of C3N4 (t-C3N4) embedded with Fe3O4 nanospheres. t-C3N4 exhibits high surface area and strong anchoring of LPS, and the Fe3O4/t-C3N4 accelerates the anchoring of LPS and improves the electronic pathways. The combination of these materials leads to remarkable battery performance with 400% improvement in a specific capacity and a low capacity decay per cycle of 0.02% at 2 C over 1000 cycles, and stable cycling at 6.4 mg cm−2 for high-sulfur-loading cathode.

Magnesium oxysulfate (MOS) whisker is considered as a promising inorganic material recently attracting a great attention for being used as a reinforcing filler for polymer composites due to high aspect ratio and extremely-low bulk density. In this study, the MOS was treated with 3-methacryloyloxypropyl-trimethoxy silane (MPS) via sol-gel condensation reactions, which successfully allowed melt mixing with polypropylene (PP) up to 30 wt% of MOS. The tensile strength at yield and modulus of the MOS/PP composites were substantially increased by 50.8% and 362%, respectively, when compared with the pristine PP. As a novel finding, the flame retardancy of MOS was proved by identifying water evolution at elevated temperatures giving out 9 wt% of water in 250–320 °C and 14 wt% in 350–420 °C in two steps. This work demonstrated that the MOS could be an excellent filler for PP not only increasing the mechanical properties in a great extent but also imposing flame retarding capability. Keywords: Magnesium oxysulfate, Surface modification, Mechanical properties, Flame retardant

A high molecular-weight thermoplastic lignin-based polymer was successfully synthesized by adjusting the degree of polymerization while inducing linear growth of lignin macromers via methylene diphenyldiisocyanate. The thermoplastic lignin-urethane polymer was desirably achieved in a narrow range of reaction conditions of 2.5 to 3.5 h at 80 oC in this study, and the molecular weight of the resulting lignin-based polyurethanes (LigPU) reached as high as 912,000 g/mole, which is far above any reported values of lignin-based polymer derivatives. The thermal stability of LigPU was greatly improved by the urethane polymerization, giving the initial degradation temperature (T2%) at 204 °C, which should be compared with T2% = 104 °C of the pristine lignin. This was due to the fact that the OH groups in the lignin macromers, having low bond-dissociation energy, were replaced by the urethane bonds. In dielectric analysis, the synthesized LigPU exhibited a softening transition at 175 °C corresponding to a combinatorial dual process of the dry Tg,dry of the lignin macromers and the softening of methylenediphenyl urethane chains. This work clearly demonstrated that a high molecular weight of thermoplastic LigPU could be desirably synthesized, broadening the lignin application for value added and eco-friendly products through common melt processes of polymer blend or composites.

Lithium-sulfur batteries (LSBs) with outstanding theoretical capacity and environmentally friendly properties are regarded as next-generation energy storage devices. However, the shuttle effect of lithium polysulfide (LPS) limits the practical application of LSBs. Herein, we introduce an aqua-processable carbon quantum dot (CQD)--assisted resilient waterborne polyurethane (WPU) network binder for sulfur cathodes. WPU is a well-dispersed colloidal system with abundant polar groups that is suitable for regulating LPS shuttle effects. CQDs were prepared from WPU by hydrothermal treatment. The CQDs enabled facile electron/ion transport, enhanced the adsorption capability of LPS, and formed a robust network. Moreover, the chemical similarity between WPU and CQDs enabled the formation of a well-dispersed system, thereby affording optimal electrochemical performance. The WPU-CQD binder systems exhibited stable cycling performance at a high rate of 2C, with only 0.028% retention decay per cycle over 1000 cycles. [ABSTRACT FROM AUTHOR]

Gel polymer electrolyte (GPE) membrane was prepared by the facile amine-epoxy crosslinking reaction of poly(ethylene glycol)diglycidylether (PEGDE) with diamino-poly(propylene oxide) (DPPO) and subsequent immersion in 1 M LiPF6 solution. To apply GPE for Si anode in a Li-ion battery, the physical properties were optimized by the degree of crosslinking which was controlled by molecular weight of each part. The crosslinked GPE membrane composed of PEGDE(1,000 g mol-1) and DPPO (4,000 g mo-1) exhibited desirable dimensional stability, low electrical resistance, adequate ionic conductivity of 1.0 mS cm-1 at 25°C. The Si anode cell employing this GPE exhibited enhanced battery performance of 2,434 mAhg-1 and 80% cyclic retention after 100 cycles. The well-optimized cGPE with desirable physical properties could resolve the issues of safety and stability resulted from volume expansion of Si as well as Li dendrite formation. [ABSTRACT FROM AUTHOR]

The synthesis and electrocatalytic performance of iridium-oxide (IrO2) are reported. IrO2 was electrochemically deposited on the gold dendrite template prepared by the chronoamperometry. The influence of the synthetic condition on the morphology, phase composition, and accessible surface area of the IrO2 dendrites was investigated. The optimized IrO2 dendrites showed an excellent electrocatalytic activity toward oxygen evolution with a low overpotential of 240 mV at 5 mAcm-2 and to the sensing of hydrogen peroxide with a high sensitivity of 692.38 μAmM-1cm-2 in a wide linear range. [ABSTRACT FROM AUTHOR]

MnO2/graphene composites were prepared for the electrode material of supercapacitors. MnO2was synthesized on a gold plate by the electrodeposition method. Graphene prepared by thermal CVD was transferred onto the MnO2layer. These processes were repeated to make multilayer structures. The optimal performance of the MnO2/graphene composite was examined as a function of the number of graphene layers in MnO2. The morphology of MnO2on graphene was confirmed by SEM and TEM, and the capacitance of the electrode was investigated by cyclic voltammetry and galvanostatic charge/discharge test. The graphene layer provides the electro-conductivity of MnO2, and then leads to enhancement of the capacitance of MnO2. [ABSTRACT FROM AUTHOR]

Various functional materials, such as metal nanoparticles, carbon nanotubes and conducting polymers were coated on polymer microspheres finding various uses in electronic and biomedical applications. Herein, we demonstrate that single graphene oxide (GO) sheets could be easily wrapped on amine-functionalized poly(glycidyl methacrylate) (PGMA-ed) microspheres (∼2.5 μm in diameter) to form a PGMA-ed/GO core-shell structure with a thickness of ca.50 nm. Subsequently, the synthesized GO-skin microspheres were consolidated by heating them to 60 °C to form a robust self-standing paper through the formation of electrostatic and van der Waals attractive forces between the very large surfaces of the GO, together with the formation of hydrogen bonding during the dewatering and drying processes, where the GO skins are interconnected to provide an electrical path and mechanical skeletal structure. When a stabilized GO dispersion was added to the PGMA-ed microspheres, the GO sheets were uniformly self-assembled on the PGMA-ed microsphere surfaces, seemingly through dipole–dipole interactions and amine–epoxide chemical reactions. This approach provides a simple route for the large volume production of PGMA-ed/GO core-shell microspheres and large-sized self-standing paper that may find various uses in optoelectronic device materials and porous membrane applications. [ABSTRACT FROM AUTHOR]

In this paper, we present a robotic actuation system using an artificial muscle actuator based on a dielectric elastomer. A novel linear actuator called a 'multi-stacked actuator' is proposed that can be embedded in the phalanges of a multi-jointed robot finger. This actuator ensures a compact design of the overall system. As an example, a 2-d.o.f. robot finger is developed and its performance under the proposed actuator system is experimentally demonstrated. The application of the proposed system can be extended easily to a multifingered robot hand and even to articulated mechanisms such as legged robots, etc. [ABSTRACT FROM AUTHOR]

An amperometric sensor for the determination of phenolic compounds in waste water was developed adopting microtubule structure of conducting polymer. The tubule structure used for enzyme immobilization was manufactured by the electrochemical polymerization of EDOT into a polycarbonate template membrane. The microtubule worked as a container retaining enzymes as well as a current collector for the electrochemical reaction of the species inside. Enzyme species, for example tyrosinase stored inside the tubule converts the phenolic substrates into quinones. The quinone product was an electrochemically detectable product, which was detected at -100 mV vs. Ag/AgCl by the tubule electrode. The calibration curve showed linearity in the range of 0∼6 μM of phenols. The Sensitivities of the biosensor for catechol were 3.1 μA/μM·cm2. [ABSTRACT FROM AUTHOR]

The article presents a study on the synthesis of thermoplastic polyether-ester elastomer (TPEE) with high molecular weight through the reactive extrusion of modified, 4,4-diphenylmethane diisocyanate (m-MDI) chain extender system. The hydroxyl terminated branched TPEE used in the research was based on dimethyl terephthalate (DMT), poly(tetramethylene etherglycol) (PTMEG), 1,4-butadiene and glycerol. The researchers say that the reactive extrusion of the m-MDI resulted to the formation of urethane bonds. They add that in the first reactive intrusion, the intrinsic viscosity (IV) and m-MDI peaked because the hydroxyl groups in the TPEE precursor were utilized in the urethane formation.

Core-shell conductive beads composed of a polystyrene (PS) core and a metallic shell of nickel-gold were investigated to identify the metal-polymer interface and the electromechanical response under a large deformation. Using dispersion polymerization, the average PS bead diameter was controlled to between 1.5 µm and 4.1 µm by adjusting the water and initiator concentrations, to give a monodispersed particle size distribution. In the electroless deposition processes of Ni followed by gold, the Ni-P shell was initially formed with a thickness of 43 nm, part of which was replaced by gold to give Ni-P and Au shell layers with thicknesses of 39 nm and 43 nm, respectively, as confirmed by transmission electron microscopy (TEM) observation. The electromechanical indentation test of a single core-shell bead showed that its resistance was 9.8 Ω/bead at a compressive deformation of 35%. [ABSTRACT FROM AUTHOR]

A conductive polymer and multi-wall carbon nanotube composite was used in fabrication of field emission (FE) electrode array. The emission electrode was prepared by using a new template method adapting a microporous membrane filter as a template. Field emission characteristics were measured with and without removing the template. The measurement was done at atmosphere of 10-6 torr. The final emission cell provides the turn on of 0.6 V/μm and current density up to 650 μA/cm2 at 1.2 V/μm. [ABSTRACT FROM AUTHOR]

Sensitivity of a glucose biosensor based on conducting polymer micro-tubule was enhanced by introducing a Pt transducer layer. Electrochemical template synthesis using polycarbonate membrane was used to fabricate the micro tubule. Glucose oxidase from Aspergillus Niger was caged into the micro tubule structure by capping the mouth of the tubule with a nano porous polycarbonate membrane. This capped tubule structure worked as a cell-array retaining enzyme inside and as a sensing current collector for the electrochemical reaction of the species retained inside simultaneously. The nano pores of the capping membrane were filled with poly (1,3-phenylenediamine) by using electrochemical polymerization. Introducing a Pt transducer layer at the bottom side of the template enhanced the sensitivity of the sensor about sixty times compared to the one having Au layer. The larger the pore size of the template was, the faster was the response and the higher was the detection current because of the faster material transport into and out of the cells. [ABSTRACT FROM AUTHOR]

Poly(divinylbenzene) (PDVB) beads (2 ∼ 4 μm) were synthesized by precipitation polymerization and their surface was modified by introducing sulfonic acid groups to yield sulfonated PDVB (sPDVB). The sPDVB cores were initially coated with a polypyrrole (PPy) layer by chemical oxidative polymerization. In the process of formation of the gold shells, gold particles were deposited onto the previously prepared PPy-sPDVB cores as a seed material by in-situ redox reaction between Au(III) and neutral PPy and, then, uniform and smooth gold shells were gently grown on the cores by employing a electroless gold plating solution. The structure of the PPy-Au/PDVB core-shells was investigated by scanning electron microscopy (SEM). The presence of zero-valent gold was confirmed by X-ray photoelectron spectroscopy (XPS). [ABSTRACT FROM AUTHOR]

A conductive polymer composite was used in fabrication of field emission(FE) electrode array. The FE electrode was prepared by using a template: polycarbonate membrane filter of 0.4 ∼ 1.2 μm diameter pores. Initially, the conductive polymer was spin-coated on the ITO glass. Polymer tubules were molded by capillary action of the polymer solution into the template. After removing the template, metal were deposited by sputtering or electroplating onto the polymer to enhance the field emission. The micro structure was then observed by using SEM and analyzed via EDAX step by step along the fabrication procedure. This structure showed that FE started at 0.6 V/μm under vacuum condition of 10-6 Torr. [ABSTRACT FROM AUTHOR]

In this work conducting polymer patterns were deposited by thermal ink jet printing technique on a plastic substrate. The poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid (PEDOT:PSS) composites were adopted as conductive inks for printing on polyester film substrate. The printed pattern has been investigated by optical microscopy and cyclic voltammetry (CV). The results have been compared to the ones obtained by other methods. No appreciable differences were noted between the electrochemical behaviors of the two samples, indicating that the thermal printing of the polymer composites did not alter appreciably the material properties. And we printed some different patterns and measure electronic properties, then metal particles were deposited onto the pattern by using direct redox reaction of the printed pattern and metal ion. [ABSTRACT FROM AUTHOR]

Surface modification of ITO with polythiophene derivative, poly(3-TUTS), was done for molecular electronic device application purpose. In order to prepare a derivative of polythiophene having n-alkyltrichlorosilane at 3-position of the thiophene ring, the monomer of thienyl-functionalized n-alkyltrichlorosilane, 11-(3-thienyl)undecyltrichlorosilane (3TUTS), was synthesized. The monomer was identified by using NMR, UV/VIS spectroscopic methods. Surfaces of ITO substrates were modified with the synthesized 3TUTS to get SAM on them. Polymerization of the SAM was done by dipping this SAM into FeCl3 solution. The polymer have been identified by using Cyclic Voltammetry, UV/VIS spectroscopy, scanning electron microscopy (SEM), DFM (Dynamic Force Microscopy) image analysis. [ABSTRACT FROM AUTHOR]

This study was focused on the preparation and characterization of conducting polymer and metal composite, PAN/Pt, electrodes showing catalytic activity in acidic aqueous media. Electropolymerization deposited PAN thin film on ITO and this film was used as a Pt matrix. The polyaniline (PAN) matrix could adopt Pt particles catalysts into polymer itself visa either way of spontaneous reaction between PAN and PtCl62- or electrochemical reduction of the Pt (IV). Both procedures ended up with the formation of PAN/Pt composites. In-situ spectroelectrochemistry was used to investigate the composite formation processes. These composite electrodes were identified with SEM and EDAX. Catalytic decomposition of methanol on these electrodes was observed by using cyclic voltammetry method. [ABSTRACT FROM AUTHOR]

Micro scale emitter array was fabricated with a conducting polymer. A simple and easy way of electrochemical template polymerization was utilized in this process. In this study the template membrane was fixed onto an ITO glass electrode by using conductive composite glue. Applying electrochemical potential to the template electrode in monomer electrolyte allowed polymerization of pyrrole within the pores and thus the micro structures were grown. Cyclic voltammetry, SEM and EDAX measurements were done to characterize this emitter array. The emission current measurements were done in 10-7 Torr condition and results show redox state dependence emission of the polymer electrodes. [ABSTRACT FROM AUTHOR]

The electrically conductive composite films based on poly(3,4-ethylenedioxythiophene) (PEDOT) were synthesized. The PEDOT/silicate composite was prepared by the in-situ oxidative polymerization of EDOT monomer using ferric toluene sulfonate (FTS) oxidant in which tetraethylorthosilicate was added to form inorganic silicate network by sol-gel transformation. The PEDOT-gold composite film was also prepared by the in-situ redox reaction between PEDOT in neutral state and AuCl 3 . The neutral PEDOT was oxidized by AuCl 3 while AuCl 3 was reduced to form Au metal. These PEDOT based composite films were repeatedly oxidized and reduced and the electrochemical and thermal stability was monitored by cyclic voltammetry. PEDOT-gold film exhibited highly enhanced electrochemical as well as thermal stability compared to PEDOT-PSS and PEDOT-silicate films. [ABSTRACT FROM AUTHOR]

This study was primarily focused on the preparation and characterization of conducting polymer/metal nanocomposites. Poly(3,4-ethylenedithiathiophene) was prepared onto ITO electrodes as thin film shapes by electrochemical polymerization and reduced with constant potential. When the polymer films were doped with K 2 PtCl 6 solution, they were easily get oxidized due to the concurrent reduction of Pt(IV) to Pt(0). This procedure ended up with the formation of polymer/metal composites. In-situ spectroelectrochemistry was used to investigate the composite formation processes. The final composites were indentified with SEM and EDAX. Catalytic decomposition of methanol on these composite electrodes was observed by using cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Conducting polymers such as polypyrrole and poly (3-hexylthiophene) have received particular interests because of easy preparation and relatively good stability. These polymers can be electrochemically synthesized in the form of thin film onto a working electrode. However, once the polymer film start to grow, all electrode surface contacted with deposition solution is to plated. The object of this research was to perform the selective electrodeposition of conducting polymers on the working electrode. This type of polymerization could be completed by adapting confined area electrolysis. Microstructures of conducting polymers were fabricated by using this method. The similar microstructures fabricated by electrochemical carving method. [ABSTRACT FROM AUTHOR]

As a new class of thermally activated actuators based on polymeric fibers, we investigated polyethylene terephthalate (PET) yarns for the development of a twisted-coiled polymer fiber actuator (TCA). The PET yarn TCA exhibited the maximum linear actuation up to 8.9% by external heating at above the glass transition temperature, 160 °C–180 °C. The payload of the actuator was successfully correlated with the preload and training-load conditions by an empirical equation. Furthermore, the PET-based TCA was electrically driven by Joule heating after the PET surface was metallization with silver. For the fast and precise control of PET yarn TCA, electroless silver plating was conducted to form electrical conductive layers on the PET fiber surface. The silver plated PET-based TCA was tested by Joule heating and the tensile actuation was increased up to 12.1% (6 V) due to the enhanced surface hardness and slippage of PET fibers. Overall, silver plating of the polymeric yarn provided a fast actuation speed and enhanced actuation performance of the TCA actuator by Joule heating, providing a great potential for being used in artificial muscle for biomimetic machines including robots, industrial actuators and powered exoskeletons. [ABSTRACT FROM AUTHOR]

Poly(3-hexylthiophene) has been renowned for having excellent electrochemical reactivity and optoelectronic functionalities. The existence of a pre-peak pair at ~0.7 V in the polymerization CV could be noticed in several references. Because this pre-peak pair is almost enveloped into the broad main peak pair. Especially the existence of them in the CV obtained from monomer free electrolyte is hardly noticed. There have been many different interpretations for the existence of the pre-peak pair. This research was to examine the appearance of the pre-peak by using new approach of electrocasting of polymer from solution. [ABSTRACT FROM AUTHOR]

Fast and accurate determination of bisphenol A (BPA) in varying matrices has become important in recent years. In this study, a cysteine-flanked heptapeptide sequence Cys-Lys-Ser-Leu-Glu-Asn-Ser-Tyr-Cys (CKSLENSYC), which is capable of recognizing BPA with high specificity, was isolated using a phage display technique. A novel electrochemical biosensor harnessing this affinity peptide as a BPA detection probe, was constructed and its performance was assessed. The formation of a self-assembled peptide monolayer on the gold electrode was confirmed by attenuated total reflection infrared spectroscopy (ATR-IR), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Following the exploration of the optimum sensing condition, differential pulse voltammetry (DPV) was used to determine the varying concentrations of BPA in the solution. The developed sensor conveyed excellent performance in view of sensing speed, sensitivity and selectivity by detecting BPA in less than 5 min with a broad dynamic detection range of 1-5000nM of BPA, despite the presence of several interfering species, such as phenolic compounds and inorganic ions. [ABSTRACT FROM AUTHOR]