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Platinum(II) complexes bearing N‐heterocyclic carbenes based guanosine and caffeine have been synthesized by unassisted C−H oxidative addition, leading to the corresponding trans‐hydride complexes. Platinum guanosine derivatives bearing triflate as counterion or bromide instead of hydride as co‐ligand were also synthesized to facilitate correlation between structure and activity. The hydride compounds show high antiproliferative activity against all cell lines (TC‐71, MV‐4‐11, U‐937 and A‐172). Methyl Guanosine complex 3, bearing a hydride ligand, is up to 30 times more active than compound 4, with a bromide in the same position. Changing the counterion has no significant effect in antiproliferative activity. Increasing bulkiness at N7, with an isopropyl group (compound 6), allows to maintain the antiproliferative activity while decreasing toxicity for non‐cancer cells. Compound 6 leads to an increase in endoplasmic reticulum and autophagy markers on TC71 and MV‐4‐11 cancer cells, induces reductive stress and increases glutathione levels in cancer cells but not in non‐cancer cell line HEK‐293. [ABSTRACT FROM AUTHOR]

Abstract: The use of biomaterials and bioinspired concepts in electronics will enable the fabrication of transient and disposable technologies within areas ranging from smart packaging and advertisement to healthcare applications. In this work, the use of a nonhalogenated biodegradable solid polymer electrolyte based on poly(ε‐caprolactone‐co‐trimethylene carbonate) and tetrabutylammonium bis‐oxalato borate in light‐emitting electrochemical cells (LECs) is presented. It is shown that the spin‐cast devices exhibit current efficiencies of ≈2 cd A−1 with luminance over ≈12 000 cd m−2, an order of magnitude higher than previous bio‐based LECs. By a combination of industrially relevant techniques (i.e., inkjet printing and blade coating), the fabrication of LEC devices on a cellulose‐based flexible biodegradable substrate showing lifetimes compatible with transient applications is demonstrated. The presented results have direct implications toward the industrial manufacturing of biomaterial‐based light‐emitting devices with potential use in future biodegradable/biocompatible electronics. [ABSTRACT FROM AUTHOR]

Carboxylic acid functional ethoxythiophene (PRODOT ‐ COOH) monomer has been synthetized and polymerized chemically and electrochemically. This monomer can be used as intermediate to prepare three additional PRODOT monomers via simple condensation with HATU or DCC and electropolymerized to afford functionalized conductive polymers. [ABSTRACT FROM AUTHOR]

ABSTRACT Polyamides (PA) constitute one of the most important classes of polymeric materials and have gained strong position in different areas, such as textiles, fibers, and construction materials. Whereas most PA are synthesized by step-growth polycondensation, PA 6 is synthesized by ring opening polymerization (ROP) of ε-caprolactam (ε-CLa). The most popular ROP methods involve the use of alkaline metal catalyst difficult to handle at large scale. In this article, we propose the use of organic acids for the ROP of ε-CLa in bulk at 180 °C (below the polymer's melting point). Among evaluated organic acids, sulfonic acids were found to be the most effective for the polymerization of ε-CLa , being the Brønsted acid ionic liquid: 1-(4-sulfobutyl)−3-methylimidazolium hydrogen sulfate the most suitable due to its higher thermal stability. End-group analysis by 1H nuclear magnetic resonance and model reactions provided mechanistic insights and suggested that the catalytic activity of sulfonic acids was a function of not only the acid strength, but of the nucleophilic character of conjugate base as well. Finally, the ability of sulfonic acid to promote the copolymerization of ε-CLa and ε-caprolactone is demonstrated. As a result, poly(ε-caprolactam- co-ε-caprolactone) copolymers with considerably randomness are obtained. This benign route allows the synthesis of poly(ester amide)s with different thermal and mechanical properties. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2394-2402 [ABSTRACT FROM AUTHOR]

Endowing unimolecular soft nanoobjects with biomimetic functions is attracting significant interest in the emerging field of single-chain technology. Inspired by the compartmentalized structure and polymerase activity of metalloenzymes, copper-containing compact nanoglobules have been designed, synthesized, and characterized endowed with metalloenzyme mimicking characteristics toward controlled synthesis of water-soluble polymers and thermoresponsive hydrogels. When compared to metalloenzymes, artificial nanoobjects endowed with metalloenzyme mimicking characteristics offer increased stability against thermal changes and reduced degradability by hydrolytic enzymes. [ABSTRACT FROM AUTHOR]

Glioblastoma-initiating cells (GICs) represent a stem cell-like subpopulation within malignant glioblastomas responsible for tumor development, progression, therapeutic resistance, and tumor relapse. Thus, eradication of this subpopulation is essential to achieve stable, long-lasting remission. We have previously reported that melatonin decreases cell proliferation of glioblastoma cells both in vitro and in vivo and synergistically increases effectiveness of drugs in glioblastoma cells and also in GICs. In this study, we evaluated the effect of the indolamine alone in GICs and found that melatonin treatment reduces GICs proliferation and induces a decrease in self-renewal and clonogenic ability accompanied by a reduction in the expression of stem cell markers. Moreover, our results also indicate that melatonin treatment, by modulating stem cell properties, induces cell death with ultrastructural features of autophagy. Thus, data reported here reinforce the therapeutic potential of melatonin as a treatment of malignant glioblastoma both by inhibiting tumor bulk proliferation or killing GICs, and simultaneously enhancing the effect of chemotherapy. [ABSTRACT FROM AUTHOR]

The added value behind reversible bonds is the possibility to develop responsive structurally dynamic materials, which can adapt their constitution and, hence, properties to external stimuli. In recent years, much effort has been devoted to the design and synthesis of single-chain polymer nanoparticles (SCNPs) that can be reversibly assembled or disassembled in response to external environmental changes or that can adapt even their structure through simple exchange reactions. Here, the evolution of the relatively new field of responsive SCNPs constructed via non-covalent, or supramolecular, interactions, and 'dynamic' covalent bonds is described in detail. The main reversible bonds commonly used in supramolecular polymer chemistry and dynamic covalent materials are summarized. A detailed description of the current reported routes to reversible unimolecular polymer nanoparticles is provided. Finally, future prospects of SCNPs constructed via supramolecular interactions and dynamic bonds are detailed. [ABSTRACT FROM AUTHOR]

Inspired by the multifunctionality of vitamin D-binding protein and the multiple transient-binding behavior of some intrinsically disordered proteins (IDPs), a polymeric platform is designed, prepared, and characterized for combined delivery of dermal protective and anticancer bioactive cargos on the basis of artificial single-chain nano-objects mimicking IDPs. For the first time ever, simultaneous delivery of folic acid or vitamin B9, and hinokitiol, a relevant natural bioactive compound that exhibits anticancer activity against human malignant melanoma cells, from these multidirectionally self-assembled unimolecular nanocarriers is illustrated. [ABSTRACT FROM AUTHOR]

Protection of acetylenic monomers is a common practice to avoid parasitic side reactions during polymerization. Herein, we report that redox-initiated RAFT polymerization allows the direct, room temperature synthesis of a variety of single-chain nanoparticle precursors (displaying narrow molecular weight dispersity, $\overline{M}_{\rm w}$/ $\overline{M}_{\rm n}$ = 1.12 -1.37 up to $\overline{M}_{\rm w}$ = 100 kDa) containing well-defined amounts of naked, unprotected acetylenic functional groups available for rapid and quantitative intrachain cross-linking via metal-catalyzed carbon-carbon coupling (i.e., C-C 'click' chemistry). To illustrate the useful 'self-clickable' character of the new unprotected acetylenic precursors, single-chain nanoparticles have been prepared for the first time in a facile and highly efficient manner by copper-catalyzed alkyne homocoupling (i.e., Glaser-Hay coupling) at room temperature under normal air atmosphere. [ABSTRACT FROM AUTHOR]

Organic electronic devices are often highlighted in terms of cost‐efficient solution processing and potential printability. However, few studies are reporting truly full‐solution‐processed devices taking into account the electrodes as well as all other layers. This results in a production method that only partially benefits from the cost efficiency of solution processing and that still depends on costly and elaborate techniques like evaporation and/or lithography. This lack of knowledge is addressed by presenting a truly fully printed light‐emitting electrochemical cell on ultraflexible parylene C substrates usable for conformable electronics. All device parts are fabricated by industrial relevant printing‐techniques under ambient atmosphere. Inkjet printing is used for the structuring of the device layout and is therefore able to implement and create arbitrary designs. Further layers are produced by blade coating which is well suited for the coating of large areas. The devices show stable operation at a luminance higher than 100 cd m−2 for 8.8 h, can reach a maximum brightness of 918 cd m−2, and exhibit a turn‐on time of 40 s to reach 100 cd m−2. Moreover, biocompatible and biodegradable materials are utilized to allow potential applications in life science and bioelectronics. Light‐emitting electrochemical cells are fabricated on a biocompatible parylene C substrate in a fully printed fabrication process. The production method utilizes digital inkjet printing allowing the layout of the pixels to be arbitrary in shape and size. The devices are highly flexible even under operation useful for possible applications in conformable electronics and life science. [ABSTRACT FROM AUTHOR]

Conducting polymer electrodes based on poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) present many advantages for biological signal recording over traditional metal electrodes and are being steadily evaluated in health monitoring applications. A main requirement for wearable electrodes based on PEDOT:PSS is that selected additives, such as crosslinking agents, avoid the redispersion of the polymer or its postprocess delamination. In this work, a novel approach is presented to fabricate water stable conducting free‐standing films and textile electrodes by using a divinyl sulfone (DVS) crosslinker. As opposed to pristine and glycidoxypropyltrimethoxysilane (GOPS)‐crosslinked formulations, the stability of the conducting PEDOT:PSS/DVS is achieved without reducing its conductivity or an extreme stiffening of its mechanical properties. PEDOT:PSS/DVS formulation is easily processed on any substrate and forms low surface resistance free‐standing or textiles electrodes. Electrochemical and stretchable properties of the PEDOT:PSS/DVS in air and in an aqueous environment are demonstrated and its performance in recordings of electrophysiological signals such as electrocardiography is evaluated. This three‐component material shows great potential for making wearable and humidity stable devices in healthcare applications. Furthermore, it can also be highly attractive for the development of washable electroactive textiles. The use of divinyl sulfone as a crosslinker in the poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonate) allows the fabrication of conformable, highly conductive, stable in water, and stretchable electrodes finding an application in cutaneous electrophysiology and enabling the development of mechanically robust wearable electronic textiles. [ABSTRACT FROM AUTHOR]

Reversible SCNPs are versatile nano‐objects for nanomedicine, sensing, and catalysis, although other different end‐use applications of SCNPs have been also proposed (e.g., self‐curing coatings and self‐healing surfaces). The evolution of the relatively new field of responsive SCNPs constructed via non‐covalent, or supramolecular, interactions and “dynamic” covalent bonds is reviewed by Ana Sanchez‐Sanchez and Jose A. Pomposo on page 11. [ABSTRACT FROM AUTHOR]

Front Cover: Guided by molecular dynamics simulation tools, single‐chain polymer nanocarriers mimicking disordered proteins are prepared under optimized experimental conditions. Of special novelty and practical interest is the combined delivery of dermal protective (folic acid) and anticancer (hinokitiol) bioactive cargos from these artificial single‐chain nano‐objects in a pH‐dependent manner. Further details can be found in the article by A. Sanchez‐Sanchez, S. Akbari, A. J. Moreno, F. Lo Verso, A. Arbe, J. Colmenero, and J. A. Pomposo* on page 1681. [ABSTRACT FROM AUTHOR]