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In situ preparation of bifunctional thiazolo[5,4‐d]thiazole (TTz)‐based fluorophore cross‐linked nanofibers is successfully performed. These multifunctional nanofibers are used as both crystal growth template and antibacterial substrate that makes bacterial detection possible simultaneously. These highly fluorescent nanofibers act as optical sensors toward many analytes. The acid, base, and metal cation‐sensitive nature of the 2,5‐bis(4‐hydroxyphenyl)thiazolo[5,4‐d]thiazole (HPhTT) dye makes the prepared PVA nanofibers sensitive against these chemicals. Metal nanoparticles (MNPs) or metal oxide crystal formation occurs on the surface of nanofibers without any reducing agent. The strong interaction between metal cations and fluorophores results in crystal formation on the surface, which is named for the first time as "complexation‐triggered crystalization." These dye cross‐linked and metal‐interacted nanofibers exhibit antibacterial effect against E. coli (ATCC 25922), S. aureus (ATCC 25923), P. aeruginosa (ATCC 27853), and E. faecalis (ATCC 25922) strains. Also, the emission wavelength change of nanofibers in bacterial contamination makes it possible to use smart nanofiber films for optical bacteria detection. These novel materials pave the way for new applications such as smart wound bands, optical sensors, and one‐step preparation of surface‐enhanced Raman spectroscopy substrate. [ABSTRACT FROM AUTHOR]

ABC-type triblock copolymers, namely poly[(ethylene glycol)methyl ether]-block-poly(tert-butyl methacrylate)-blockpoly[ 2-N-(diisopropylamino)ethyl methacrylate] (MPEG-b-PBuMA-b-PDPA), were first synthesized and then the middle blocks were successfully converted into poly(methacrylic acid) to obtain MPEG-b-PMAA-b-PDPA zwitterionic triblock copolymers. These block copolymers were soluble in water and formed micellar aggregates with complex cores via hydrogen bonding interactions between MPEG and PMAA blocks below pH 4.0. When the pH was between 5.0 and 7.0, due to charge compensation between partially protonated PDPA and partially ionized PMAA blocks, micelles with polyion complex cores were observed. If the solution pH was above 8.0, deprotonation of tertiary amine groups provided a hydrophobic character to the PDPA block, which resulted in the formation of PDPAcore micelles while MPEG/anionic PMAA hybrid blocks formed hydrated coronas. Intermediary layer cross-linked (ILCL) micelles from PDPA-core micelles were also prepared by cross-linking the inner PMAA shell. The hydrophobic drug dipyridamole (DIP) was used to investigate the release profile of ILCL micelles. DIP can be loaded to the PDPA cores of the micelles in basic aqueous media. An increase in the degree of cross-linking causes slower release for the model drug. It was concluded that the more complex matrix formation in the intermediary layer of the micelles via cross-linking retards the drug release from the core. [ABSTRACT FROM AUTHOR]

The aim of this study is to highlight the use of polystyrene (PS) latexes stabilized with block copolymers as a hard template in the production of metal oxide hollow spheres. PS latexes produced by dispersion polymerization by stabilizing with tertiary amine methacrylate-based diblock copolymer were used as a hard template in the preparation of nickel manganese oxide (NiMn2O4) hollow spheres and cobalt iron oxide (CoFe2O4) bowl-like structures. Thanks to the diblock copolymer stabilizer with tertiary amine functional groups on the PS surface, precursor salts of CoFe2O4 and NiMn2O4 were first homogeneously deposited on the surface of PS latexes with a controlled precipitation technique. Then, metal oxide hollow spheres and bowl-like structures were produced by calcination. XRD results showed that CoFe2O4 and NiMn2O4 structures were successfully obtained after calcination. The thermogravimetric analysis results showed that the CoFe2O4 and NiMn2O4 contents of the hybrid PS spheres were in the range of 26.0-28.6 wt%. SEM images showed that the inorganic-polymer spheres fused with each other after calcination to form larger magnetic CoFe2O4 bowl-like structures. SEM images also indicated successful production of highly rough NiMn2O4 hollow spheres with nanosheets on the surface. [ABSTRACT FROM AUTHOR]

Cross-linked and flexible poly(vinyl acetone ketal) (PV-A-K) films have been prepared as a result of ketalization reaction and monolith formation of poly(vinyl alcohol) (PVA), which has the feature of forming films quickly and is frequently used in biological fields. In this novel method, flexible PVA-K films have been produced simply and in a short time accompanied by monolith formation without any catalyst in acetone. The effect of acetone ratio on the physical properties (i.e., swelling and mechanical properties) of such formations has been investigated to reveal significant influences of it. In addition, zinc oxide (ZnO) nanoparticles synthesized via the solvothermal method have been doped into PV-A-K films during film preparation. The prepared PV-A-K and ZnO doped PV-A-K films have been characterized with SEM, XRD, and FT-IR. Their mechanical properties have been investigated with a universal mechanical test machine. The acetone ratio is quite effective both on the porosity and stress/strain properties of the films. Antibacterial activities of the films are evaluated against four different strains (E. coli, S. aureus, P. aeruginosa, and E. faecalis) via the disk diffusion method. The films are selectively effective against S. aureus. These highly flexible and elastic films have great potential for biomedical applications, wound dressing, and antibacterial surface preparation. [ABSTRACT FROM AUTHOR]

Abstract Topical applications that reduce systemic toxic effects while increasing therapeutic efficacy are a promising alternative strategy. The aim of this study was to provide an enhanced transdermal delivery of low molecular weight heparin (LMWH) through the stratum corneum by using cationic carrier as a novel permeation enhancer. Recent studies have shown that heparin-conjugated biomaterials can be effective in inhibiting tumor growth during cancer treatment due to their high ability to bind growth factors. Paclitaxel (PCL) was co-encapsulated into the same cationic carrier for the purpose of improving of therapeutic efficacy for a combined cancer treatment with LMWH. In vitro and in vivo studies showed that the LMWH and PCL release was significantly affected by polymer molecular weight and block composition. Skin penetration tests have indicated that larger amounts of LMWH were absorbed from LMWH-gel conjugate through SC, than aqueous formula. However, it was found that the plasma transition of LMWH released from gel conjugate was lower compared to the plasma concentration of LMWH released from aqueous solution. It is recommended that PCL-loaded LMWH-conjugated core/shell hydrogels can be used as promising drug release systems for transdermal applications that can improve therapeutic efficacy and reduce side effects in a combined cancer treatment. Graphical abstract Unlabelled Image Highlights • LMWH-conjugated cationic core/shell hydrogels were successfully developed. • Paclitaxel (PCL) was simultaneously encapsulated into the hydrophobic core of these hydrogels. • Both in vitro and in vivo studies demonstrated the slow sustained release profiles of hydrogels. • Skin permeation tests showed that cationic core/shell hydrogels effectively delivers LMWH to the deeper dermal layers. • LMWH-conjugated cationic core/shell hydrogels could be promising carriers for transdermal drug delivery system. [ABSTRACT FROM AUTHOR]

Abstract: Layer‐by‐layer (LbL) films of micelles of poly[2‐(dimethylamino)ethyl methacrylate]‐b‐poly[(2‐(diethylamino)ethyl methacrylate)] (PDMA‐b‐PDEA) and poly(sodium 4‐styrenesulfonate) (PSS) with remarkably different pH‐stability and release properties are obtained via tuning film deposition conditions in a narrow pH and temperature range. Multilayers constructed at pH 8.5/25 °C or pH 8/30 °C completely disintegrate at physiologically related conditions, whereas film deposition at pH 8/25 °C produces stable films under the same conditions. Importantly, despite their stability, pH 8/25 °C multilayers release a considerable amount of pyrene at moderately acidic pH due to disintegration of the micellar cores. The amount of pyrene increases significantly at body temperature due to lower critical solution temperature (LCST)‐type phase behavior of PDMA coronal chains. The difference in properties of multilayers is explained by the extent of association among the layers which can be tuned by film deposition conditions in a narrow pH and temperature range due to dual responsive, that is, pH and temperature behavior of PDMA‐b‐PDEA micelles. [ABSTRACT FROM AUTHOR]

Poly(methyl methacrylate) (PMMA), poly(ethyl methacrylate) (PEMA), and their nanocomposites (Kao-PMMAs and Kao-PEMAs) with various kaolinite intercalation compounds were prepared in several solution polymerization media in order to examine relations between solubility parameters of polymerization medium including monomer and solvent/solvents and of intercalating agents and thermal properties of the resultant materials. The measurements of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetry/derivative thermogravimetry, and differential scanning calorimetry were used to characterize these materials. The increase in solubility parameter of polymerization medium improved thermal decomposition temperatures of PEMA and Kao-PEMAs when it usually induced a decrease in those of PMMA and Kao-PMMAs and in glass transition temperatures of all materials. These results were also examined in respect of the effects of hydrogen bonding and dispersion components of solubility parameters of intercalating agents on the thermal properties of these materials. POLYM. COMPOS., 37:2333-2341, 2016. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

An ABA-type triblock copolymer was synthesized through group-transfer polymerization by using poly[2-(diethylamino) ethyl methacrylate] (PDEA) as A block and poly[2-(dimethylamino) ethyl methacrylate] (PDMA) as B block. By utilizing the 1,3-propane sultone to obtain polyzwitterionic triblock copolymer under moderate conditions, PDMA block of the triblock copolymer has been selectively betainized. The selectively betainized block copolymer and its precursor were molecularly dissolved in acidic aqueous media without any use of cosolvent at room temperature. In both cases, an increase in solution pH caused near monodisperse cationic or neutral flower-like micellization with hydrophobic PDEA-core at basic aqueous solution. However, at higher polymer concentrations where precursor triblock copolymer does not exhibit any gelling behavior (10% and higher), polyzwitterionic copolymer derivative can be gelated as a result of inter-chain integration of polyzwitterionic groups. Furthermore, the load of risperidone (RISP) into gel matrix and release studies have been successively realized. The results indicated that the betainized novel gel is appropriate for using as a pH- and salt-controlled risperidone-releasing system. [ABSTRACT FROM AUTHOR]

In this study, an amphiphilic poly(ethylene glycol)methyl ether- block-poly(glycidyl methacrylate) diblock copolymer (MPEG- b-PGMA) was synthesized via atom transfer radical polymerization (ATRP), and its micellar solution was prepared in acetone/water mixture. Core cross-linked (CCL) micelles were synthesized by cross-linking the epoxy functional group of poly(glycidyl methacrylate) block with ethylenediamine. These CCL micelles were used in the synthesis and stabilization of platinum nanoparticles (PtNPs) in aqueous media. Transmission electron microscopy (TEM) images showed that well-dispersed PtNPs with a diameter of around 5 nm were formed within the MPEG- b-PGMA spherical CCL micelles having 22.0 ± 3.0 nm diameters. The mean TEM diameter of the PtNPs is of the order of several nanometers, which is consistent with the plasmon absorption peaks observed at around 205 and 261 nm. The catalytic activity of CCL micelle-PtNP dispersion was also investigated in the reduction of p-nitrophenol to p-aminophenol in the presence of NaBH. The results showed that the PtNPs exhibit a good catalytic activity toward reduction of p-nitrophenol. CCL micelle-stabilized PtNP dispersions were stable for long periods of time without changing properties at room temperature. CCL micelles found to be good hostage or stabilizer for the NPs in aqueous media. [ABSTRACT FROM AUTHOR]

We report the synthesis and characterization of water soluble star copolymers based on 2-( N -dimethylamino)ethyl methacrylate, 2-( N -diethylamino)ethyl methacrylate, and 2-( N -morpholino)ethyl methacrylate monomers via group transfer polymerization. Ethylene glycol dimethacrylate was used as a branching agent. Highly cross-linked heteroarm star copolymers were obtained with narrow molecular weight distributions and controlled molecular architectures. Star copolymers were obtained in good yield with a monomer/branching agent at the appropriate mole ratio without macrogelation. Additionally, analog linear diblock copolymers with similar comonomer ratios were also synthesized to make comprehension. Star copolymers had lower viscosities compared to linear analogs at pH 8.1. Critical micelle concentration and critical micellization pH values were also determined for these star copolymers and compared to linear diblock copolymers. All polymers were characterized using gel permeation chromatography combined with a light scattering and a refractive index detectors and 1 H NMR spectroscopy, to determine the molecular weights, molecular weight distributions and comonomer compositions, respectively. Solution behaviors of the polymers were also analyzed with a viscometer, densitometer, and surface tensiometer. [ABSTRACT FROM AUTHOR]

Abstract: We report on bacterial anti-adhesive properties of a monolayer of block copolymer micelles (BCMs) with zwitterionic coronae and pH-responsive cores. BCMs were obtained by pH-induced self-assembly of selectively betainized poly[3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate-b-2-(diisopropylamino)ethyl methacrylate] (βPDMA-b-PDPA) in aqueous solution above neutral pH. Monolayer films were self-assembled at pH7.5 when βPDMA-b-PDPA was in the micellar form. Bacterial anti-adhesive properties of the zwitterionic micellar coatings were examined against S. aureus through: i) a macroscopic test based on viable cell counting; ii) direct microscopic visualization of adherent bacteria by live/dead staining and iii) crystal violet staining to evaluate surface adherent biomass. 95% reduction in cell adhesion was observed by microscopy indicating the anti-adhesive properties of βPDMA-b-PDPA micellar monolayer. Results obtained from the viable cell count assay and crystal violet staining showed similar trends and were in good agreement with the microscopy results. Such coatings are promising to impart both anti-adhesive and antimicrobial properties to a surface due to bacterial anti-adhesive properties of zwitterionic coronae and the potential of pH-responsive cores to release antimicrobial agents. [Copyright &y& Elsevier]

We report novel smart films with superior optical properties. Orthoester structure formation in the films cause recyclable acid-base interactions resulting with emission wavelength shift. They are also useful material in the production of AuNP and PbO crystals. [Display omitted] • Novel usage of HPhTT dye as highly fluorescent cross-linker to prepare PVA films. • Tunable emission wavelength depending acid, base and dye concentraion resulting from orthoester backbone formation. • Highly sensitive recyclable fluorescent and colorimetric sensor films against acid, base (0.2 µM) and gold in solution. • Additive free AuNP and PbO crystal formation in/on films. • AuNP decorated PVA film usage as SERS substrate. 2,5-Bis(4-hydroxyphenyl)thiazolo[5,4- d ]thiazole (HPhTT) molecule was synthesized and used as cross-linker in nanotubular self-assembled film preparation. Highly fluorescent, insoluble, PVA based smart films were obtained via orthoester backbone formation at basic media. Both the emission wavelength (λ em) and photoluminescence (PL) intensity of the films were observed as strongly dependent on dye and base concentrations. These fluorescent films were highly sensitive against acid and base resulting from halochromic property of the cross-linker. These films reversibly changed their colors and λ em when treated with TFA and NH 3 solutions as a result of dynamic covalent chemistry of orthoester groups. λ em and PL intensity of these talented films also changed when they were treated with Au, Pt, Ag, Pb, Cd, Co metal cations. Gold, TFA and NH 3 sensitivities of the films make them suitable and promising candidates as chemosensors. The films also selectively reduced gold ions and caused formation of AuNPs on the surface with simultaneous color change, blue shift in λ em and fluorescent quenching. Green synthesis of hexagonal PbO crystals are also achived inside the films simultaneously. AuNPs on the film and PbO crystal-PVA composite film are characterized with XRD and SEM analysis. These films also exhibited elastic hydrogel property after treatment of acid, base and water. The change in mechanical tensile properties of the films before and after treatment were investigated with stress-strain analysis. Photoluminescence quantum yield (PLQY) of the films were measured as to be between 14% and 39%. Increasing NaOH and dye concentration lead to red shift at λ em and higher PLQY. [ABSTRACT FROM AUTHOR]

Abstract: A series of novel pH-responsive ABA triblock copolymer gelators have been synthesized by using poly[2-(diisopropylamino)ethyl methacrylate] (PDPA) as the A block and poly[2-(dimethylamino)ethyl methacrylate] (PDMA) as the B block via group transfer polymerization. While the PDPA-b-PDMA-b-PDPA triblock copolymers are molecularly soluble in acidic aqueous media due to protonation of all tertiary amine groups, they formed either gels by the chain-end hydrophobic interactions with relatively high polymer concentration (10 wt%) or near monodisperse “flower” micelles with low polymer concentration at neutral and basic aqueous solutions. The hydrophobic model drug release was studied in a sustained manner from the gels at pH 7.4 by varying the polymer concentration, the polymer molecular weight and the temperature of the medium. Preliminary studies indicate that both slow, sustained release and fast, triggered release of a model hydrophobic drug, dipyridamole, can be achieved by tuning the solution pH, polymer concentration, polymer molecular weight and temperature of the gel. [Copyright &y& Elsevier]

Abstract: A series of poly[2-(diisopropylamino)ethyl methacrylate]-block-poly[2-(N-morpholino)ethyl methacrylate], [PDPA-b-PMEMA], have been synthesized by using group transfer polymerization. These novel PDPA-b-PMEMA diblock copolymers dissolved molecularly in aqueous solution at low pH (<6.0) due to the protonation of all tertiary amine residues of both blocks and formed PDPA-core micelles at pH 7.5 by PMEMA block forming the micelle coronas. On the other hand, it was also observed that these diblock copolymers formed near-monodisperse ‘reverse micelles’, PMEMA-core micelles, in n-alkanes with or without requiring cosolvent depending on comonomer ratios. Dynamic light scattering studies indicated monodisperse or near-monodisperse micelles in both cases. The intensity-average radii of the PDPA-core and the PMEMA-core micelles were between 10nm and 17nm (polydispersity index, μ 2/Γ 2 <0.08) and between 10nm and 13nm in n-hexane (μ 2/Γ 2 <0.09), respectively. [Copyright &y& Elsevier]

Abstract: The inhibitive performance of novel synthesised water-soluble triblock copolymers – 2-(diethylamino)ethyl methacrylate-block-2-(dimethylamino)ethyl methacrylate-block-2-(N-morpholino)ethyl methacrylate [PDEA-PDMA-PMEMA] and 2-(diisopropylamino)ethyl methacrylate-block-2-(dimethylamino)ethyl methacrylate-block-2-(N-morpholino)ethyl methacrylate [PDPA-PDMA-PMEMA] of two different molecular weight – on the corrosion behaviour of mild steel in 0.5M HCl were investigated using potentiodynamic polarisation, electrochemical impedance spectroscopy and linear polarisation methods. Polarisation curves indicate that all studied copolymers were acting as mixed type inhibitors. All measurements show that inhibition efficiencies increase with increase in inhibitor concentration. This reveals that inhibitive actions of inhibitors were mainly due to adsorption on steel surface. Adsorption of these inhibitors follows Langmuir adsorption isotherm. Thermodynamic parameters of adsorption (K ads, ΔG ads) of studied triblock copolymers were calculated using Langmuir adsorption isotherm. The variation in inhibitive efficiency mainly depends on the type and the nature of the substituents present in the inhibitor molecule and also depends on the molecular weight of the inhibitors. The correlation between the inhibition efficiencies of studied triblock copolymers and their molecular structures has been investigated using quantum chemical parameters obtained by PM3 semi-empirical SCF-MO methods. These results indicate that adsorption of studied triblock copolymers depends on the charge density of adsorption centres and dipole moments. [Copyright &y& Elsevier]

2-(dimethylamino)ethyl methacrylate (DMA) was block copolymerized in turn with three other tertiary amine methacrylate comonomers, namely 2-(diethylamino)ethyl methacrylate (DEA), 2-(diisopropylamino)ethyl methacrylate (DPA) and 2-(N-morpholino)ethyl methacrylate (MEMA), using group transfer polymerization (GTP). The DMA residues of each of these diblock copolymers were selectively betainized using 1,3-propane sultone under mild conditions to yield a series of novel betaine diblock copolymers. These selectively betainized copolymers could be dissolved molecularly without co-solvents in aqueous media at room temperature, with micellization occurring reversibly on judicious adjustment of the solution pH, temperature or electrolyte concentration. In all three cases, stable block copolymer micelles were formed with betainized-DMA coronas and hydrodynamic diameters of 10–46 nm. The selective betainization of the DMA residues dramatically reduces the surface activity and increase the solubility of the tertiary amine methacrylate block copolymers (DMA–DEA, DMA–DPA and DMA–MEMA). [Copyright &y& Elsevier]

Poly(methacryloyloxy quinoline) microparticles were synthesized and used as reducing and stabilizing agents to prepare Au/Pt bimetallic nanoparticle (NP) decorated microparticle (MP) hybrid catalyst systems. These newly reported hybrid catalyst systems were used for reduction of styrene into ethylbenzene. Gold precursor was essential to prepare bimetallic NPs due to its great interaction with PMAQ resulting in the reduction to AuNPs on the surface of PMAQ MPs. Pt is also contrubute to NP formation thanks to this superior interaction between Au and PMAQ MPs. The bimetallic nanoparticle contents on the PMAQ MPs were determined as Au0.85Pt0.15 via XRD analysis. Au and Pt amounts were also determined with ICP-MS analysis. Although the metal amount in the sample was quite low, the catalytic effect was remarkable for hybrid system. AuNP decorated MPs had no catalytic activity for the reduction of styrene. Thus, it is clear that Pt was the active part of hybrid catalyst system for this reaction. On the other hand, gold precursor had been determined as crucial for the simultaneous synthesis of bimetallic NP decorated MPs as well. New microparticles decorated with bimetallic nanoparticles have been synthesized and used effectively as a catalyst systems in the hydrogenation of styrene. While it is reported in the literature that such particles have successful catalytic activity in various oxidations, our particles stand out with reducing activities, reusabilities and easy production/removal properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • 2,5-bis(4-hydroxyphenyl)thiazolo[5,4- d ]thiazole fluorophore was used to prepare in-situ cross-linked nanofiber that enables reductant-free, green synthesis of AgNPs on the surface. • AgNPs decorated PVA nanofibers was successfully prepared and used as SERS substrate. • AgNPs decorated PVA nanofibers SERS substrate was successfully applied to the ultra-sensitive detection of organic pollutants. • R6G and pNP molecules could be detected up to 10−13 M using AgNPs decorated PVA nanofibers SERS substrate. Detection and particularly quantitative analysis of organic pollutants such as rhodamine 6G (R6G), and p-nitrophenol (pNP) in water are very important for both human health and the ecological environment. In this study, we synthesized as a facile and low cost method silver nanoparticles on poly(vinyl alcohol) (PVA) nanofibers to prepare a film based surface enhancement Raman scattering (SERS) substrate for label free molecular detection. Detection of the R6G molecule with the obtained SERS substrate is possible even at concentrations as low as 10−12 M and therefore the obtained SERS substrate indicated excellent molecular sensitivity for R6G molecule. Limit of detection value (LOD) was determined as 1.07 × 10−13 M while the enhancement factor (EF) of the obtained SERS substrate was calculated as 1.06 × 109 for the R6G molecule. A fluorophore molecule named as 2,5-bis(4-hydroxyphenyl)thiazolo[5,4- d ]thiazole (HPhTT) was effectively used for cross-linking of PVA nanofibers to use them as growth template for silver nanoparticles (AgNPs) formation on the surface without any reducing and stabilizing agent thanks to unique properties of HPhTT. Green and one pot preparation of such SERS substrates can pave the way for easily prepared commercial substrates. Moreover, AgNPs decorated PVA nanofiber-based SERS substrate has high reproducibility and good stability for SERS detection of organic pollutants. Obtained SERS substrate is expected to be applicable as a label-free sensor for various chemical and biological molecules. [ABSTRACT FROM AUTHOR]

[Display omitted] • D-A-D type chemosensor molecule (MPhTT) synthesis and its optical response to various analytes. • Fluorescent hydrogel film preparation by using MPhTT as cross-linker. • Anion, cation, acid, base detection by fluorescent hydrogel films. • Increasing chemosensing ability of the fluorophore by cross-linking in the preparation of polymer films. • Extended mechanical properties and swelling behaviors of the films. 2,5-Bis(4-hydroxy-3-methoxyphenyl)thiazolo[5,4- d ]thiazole (MPhTT) fluorophore as a donor–acceptor-donor (D-A-D) type sensor molecule is synthesized for further investigation of sensing ability of the molecule towards various anions and cations. The MPhTT molecule with strong photoluminescence (PL) has been determined to be sensitive against anions with an effective deprotonation mechanism. MPhTT molecule has been demonstrated to have a limited ability to recognize anions by PL response in the solution while selectively sensitive against CN− anion after being embedded into filter paper. Moreover, metal cations detection in the solution is impossible with the MPhTT fluorophore. The use of MPhTT dye as a cross-linker to prepare highly emissive PVA hydrogel films resulted in a reusable chemosensor for acid, base, CN− anion, and metal cations. The mechanical properties of the films and their swelling behavior have also been investigated to show their water-responsive mechanical properties and water intake ability for possible biomedical applications. These findings indicate that increasing the chemosensing ability of the dye by cross-linking of polymers can be used for many fluorophores as an innovative approach. The films with extended mechanical properties can be used for wound dressing, biosensors, moisture sensors, and many other applications. [ABSTRACT FROM AUTHOR]

An amphiphilic poly(ethylene glycol)methyl ether- block-poly(glycidyl methacrylate) (MPEG -b-PGMA) diblock copolymer is first synthesized via atom transfer radical polymerization. Epoxy groups of this precursor block copolymer are converted to hydroxyl and tertiary amine residues by reacting with diethyl amine over a ring-opening reaction. The resulting diblock copolymer is poly(ethylene glycol)methyl ether- block-poly(3-diethylamino-2-hydroxypropyl methacrylate) (MPEG -b-PDEAHPMA). Micellar solution of this diblock copolymer is prepared at pH 12.0 in aqueous media. At high pH (12.0), core - shell micelles are formed with PDEAHPMA-core and M PEG-shell. PDEAHPMA blocks have both hydroxyl and tertiary amine groups that provide reactivity against divinyl sulfone (DVS) and a response to solution pH, respectively. Cross-linking of hydroxyl groups of PDEAHPMA chains in the micelle core is successfully achieved by adding DVS. At pH 2.0, the DEAHPMA-core of core cross-linked (CCL) micelles becomes protonated and hence swelling is observed. The effect of varying the DVS concentrations is also studied. The micelle formation of diblock copolymer and its response to solution pH are investigated by using surface tensiometer, 1H NMR spectroscopy, and dynamic light scattering (DLS) techniques. CCL micellar structure and its response to solution conditions are investigated with transmission electron microscopy and DLS studies, respectively. [ABSTRACT FROM AUTHOR]

Highlights: [•] We report stimuli-responsive AB, ABA and BAB type novel block copolymers. [•] First, glyco and tertiary amine methacrylate-based block copolymers were synthesized via ATRP. [•] Glycoblocks were then converted to water soluble blocks via deprotection process. [•] All block copolymers had thermo-responsive behavior in alkali solutions. [•] They formed well-defined core–shell micellar structures at high temperatures (pH>8). [Copyright &y& Elsevier]

Fluorescent poly(methacryloxy quinolin) microparticles have been successfully synthesized and used in the synthesis of AuNPs and additive-free evolution of spherical AuNPs to raspberry-like nanostructures. These microparticles have great response to gold ions and allows simultaneous gold detection from aqueous solution. Dedection of Au and one-step synthesis of spherical and raspberry-like AuNPs in a quite short time is a remarkable development in the nanoparticle technology. • First report on the preparation of flourescent PMAQ microparticles. • Novel microparticles having great interaction with metal cations. • Gold sensing with flourescent quenching mechanism. • Gold nanoparticle formation and evolution of gold from seed to crystals. • Easy preparation of raspberry-like AuNPs and AuNP decorated microparticles with simultaneous detection of gold existence. Novel, fluorescent polymer particles based on poly(8-methacryloxy quinoline) (PMAQ) have been synthesized via suspension and mini-suspension polymerization with a diameter between 400 nm and 4 µm. Usage of sodium dodecyl sulfate (SDS) co-stabilizer causes formation of smaller microparticles with rough surfaces. Easy, one step and additive free synthesis of gold nanoparticles (AuNPs) is firstly achieved by using these new fluorescent microparticles as electron donor material and stabilizer. It is observed that the surfaces of the microparticles is successfully covered by a self-assembled layer of AuNPs. An evolution for different stages of AuNPs formation on PMAQ microparticles or colloidal raspberry-like AuNPs is offered. Raspberry-like AuNPs consist of hundereds of smaller AuNPs that result in higher surface area. Hovewer, Au nanocrystals on PMAQ are obtained in the last stage of evolution. Gold existense is also detected simultaneously due to its fluorescence quenching property during interaction with microparticles. Moreover UV-light assisted AuNPs synthesis on the PMAQ microparticles is achived in a quite short time. The Au content of the AuNP-polymer hybrid particles is determined to be 12 wt%with ICP-MS studies. These unique particles are promising candidates for various applications such as in catalysis, biosensor technology, biomedical applications, and easily prepared SERS substrates. [ABSTRACT FROM AUTHOR]

Graphical abstract Homopolymer of glycidyl methacrylate and its diblock and triblock copolymers with poly(ethylene glycol)methyl ether and methyl methacrylate were successfully synthesized via atom transfer radical polymerization. Epoxy groups of PGMA blocks were then converted to hydrophilic form by reacting with secondary amines (morpholine, 1-methylpiperazine and diethyl amine) over a ring-opening reaction. This ring-opening reaction caused the formation of hydroxyl and tertiary amine residues on each GMA unit. Tertiary amine residues of resulting derivative block copolymers were further converted to quaternary form with alkyl halides via quaternization reaction. The synthesized derivative polymers had stimuli-responsive nature. They well respond solution pH, temperature and ionic strength. With this study, it is demonstrated that PGMA-containing polymers provide us a great way to prepare different polymeric structures with various stimuli-responsive moieties via multi-step derivative reactions. With this low-cost pathway, by use of the modified PGMA (co)polymers, new stimuli-responsive (co)polymers with various content and architecture can be synthesized. These resulting (co)polymers might be more useful in various applications when compared to polymers that are too abundant in the literature. Highlights • Production of poly(glycidyl methacrylate)-based block copolymers via ATRP chemistry. • pH, temperature and ionic strength responsive polymers. • Ring-opening reaction of poly(glycidyl methacrylate) with secondary amines. • Block copolymer micelles in aqueous solution. Abstract Poly(glycidyl methacrylate) (PGMA) homopolymer, poly(ethylene glycol)methyl ether- block -poly(glycidyl methacrylate) (MPEG- b- PGMA), poly(methyl methacrylate)- block -poly(glycidyl methacrylate) (PMMA- b -PGMA) diblock copolymers, and poly(ethylene glycol)methyl ether- block -poly(glycidyl methacrylate)- block -poly(methyl methacrylate) (MPEG- b- PGMA- b -PMMA) triblock copolymers with different molecular weights and polymerization degrees were successfully synthesized via atom transfer radical polymerization. Epoxy groups of PGMA blocks were converted to hydroxyl and tertiary amine residues by reacting with secondary amines (morpholine, 1-methylpiperazine and diethyl amine) over a ring-opening reaction. Additionally, derivative (co)polymers containing poly(2-hydroxy-3-methyl piperazinepropyl methacrylate) (PHMPPMA) have also been quaternized with different alkyl and aryl halides. Aqueous solution behaviours of resulting functional polymers including poly(3-diethylamino-2-hydroxypropyl methacrylate) (PDEAHPMA), poly(2-hydroxy-3-morpholinepropyl methacrylate) (PHMPMA), PHMPPMA and its quaternarnized form PQHMPPMA homopolymers and their block copolymers with MPEG and/or PMMA were investigated by varying solution conditions such as pH, ionic strength and temperature. Their solution behaviours were investigated by using proton nuclear magnetic resonance spectroscopy and dynamic light scattering techniques. [ABSTRACT FROM AUTHOR]

ABSTRACT: This study reports the synthesis of poly(ethylene glycol)methyl ether‐block‐poly(glycidyl methacrylate) (MPEG‐b‐PGMA) diblock, and poly(ethylene glycol)methyl ether‐block‐poly(glycidyl methacrylate)‐block‐poly(methyl methacrylate) (MPEG‐b‐PGMA‐b‐PMMA) triblock copolymers via atom transfer radical polymerization and their self‐assembly behaviors in aqueous media by using acetone as cosolvent. These block copolymers formed near monodisperse core–shell micelles having cross‐linkable cores. Two types of cross‐linked micelles, namely spherical MPEG‐b‐PGMA core cross‐linked (CCL) micelles and MPEG‐b‐PGMA‐b‐PMMA interlayer cross‐linked (ILCL) micelles, were also successfully prepared from these block copolymers by using various bifunctional cross‐linkers such as hexamethylenediamine (HMDA), ethylenediamine (EDA), and 2‐aminoethanethiol (AET). Cross‐linking was successfully carried out via ring‐opening reactions of epoxy residues of hydrophobic‐cores with primary amine or thiol groups of bifunctional cross‐linkers. Finally, these cross‐linked micelles were successfully used as nanoreactors in the synthesis of gold nanoparticles (AuNPs) in aqueous media. Both CCL and ILCL micelles were found to be good stabilizers for AuNPs in aqueous media. Both CCL‐ and ILCL‐stabilized AuNP dispersions were stable for a long time without any size changes and flocculation at room temperature. These cross‐linked stabilized AuNPs exhibited good catalytic activities in the reduction of p‐nitrophenol. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 514–526. [ABSTRACT FROM AUTHOR]

A multi-responsive microgel having response to pH, temperature, and salt concentration was successfully prepared using a water-soluble monomer. Microgels were readily prepared from 2-( N-morpholino)ethyl methacrylate (MEMA) via emulsion polymerization using glycidyl methacrylate as a comonomer cross-linker. The morpholino groups of MEMA residues of microgels were able to give complexation with metal containing anions such as AuCl in acidic conditions. The reduction of aurate ions with sodium borohydride led to immobilized-gold nanoparticles (AuNP) in the microgel system. Average particle diameters of AuNPs were determined to be 10 ± 2 nm. The resulting AuNP-microgel system was examined as a nanoreactor for catalyst system and determined to be very effective in the reduction of 4-nitrophenol model reaction in aqueous media. AuNPs-microgel composite system had antibacterial properties against several Gram-positive and Gram-negative bacteria similar to amoxicillin. This P(MEMA- co-GMA) microgel is also very useful for different applications such as a host for metal nanoparticle production, a drug carrier or drug delivery system. [ABSTRACT FROM AUTHOR]

Objective: Biosurfactants are surface-active substances produced by microorganisms. The growth of microorganism supports biosurfactant production on hydrocarbon polluted environments. In this study, the capacity of biosurfactant production of Georgenia daeguensis (accession number, KP798810) isolated from hydrocarbon- contaminated soil was studied. Methods: The components of biosurfactant production medium were investigated through Plackett-Burman methodology. By using Placket-Burman based on statistical screening, six of the eleven factors of production medium were found to be critically effective on the biosurfactant production. Results: The significant factors were KCl, ZnSO4.7H2O, CaCl2.2H2O, KH2PO4, MgSO4.7H2O and glucose. Among of these, KCl had the highest effect contribution with 55.22%. After the optimization by such design, critical micelle concentration value was reached to 2.2 g L-1. When antibacterial activity of biosurfactant was screened, it showed antibacterial effect against to Klebsiella pneumoniae. Besides, the biosurfactant was characterized by FT-IR, critic micelle concentration and zeta analysis. Conclusion: This study reported that Georgenia daeguensis is able to produce effective biosurfactant exhibiting antibacterial activity against K. pneumoniae. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel method named as "phase separated micellar self assembly"to prepare micellar self assembled film in the liquid–air interface. • TTz based cross-linkers usage for highly luminescent film preparation. • Epoxy ring belonging to PGMA block of MPEG- b -PGMA- b -PDEAEMA triblock copolymer modification with TTz containing fluorophores. • Smart films as PrHCl drug delivery system for infantille hemangioma treatment and optical detection of drug release. Polyethylene glycol monomethyl ether– block -poly(glycidyl methacrylate)- block- poly[2-(diethylamino)ethyl methacrylate] triblock copolymer was synthesized to prepare self-assembled micron sized films via a novel approach named as "phase separated micellar self assembly method". Liquid-air interface self assembly method via slow solvent evaporation was used to obtain micellar films. Cross-linking of polymer films was carried out by diffusion of fluorophore cross-linker into polymer solution from subphase. In-situ micellar formation was triggered via driven forces such as molecular interactions and slow evaporation of solvent. Thiazolo[5,4- d ]thiazole based cross-linker fluorophores containing alkali subphases were used to prepare highly fluorescent cross-linked micellar films. Micellar morphologies of the films were characterized with SEM while the cross-sections of fluorophore cross-linked films were observed with TEM analysis to examine diffusion of the dye as nano-sized particles into the polymer film. Convenience and usability of the micellar films as drug delivery material were demonstrated with Propranolol HCl release via UV–Vis spectroscopic studies. Optical properties of the films before and after drug release were determined via photoluminescence spectroscopy to be able to sense the completion of the drug release process. Swelling and shrinkage properties of the films were also determined in different pH values. These highly fluorescent polymer films have great potential as drug delivery materials and biomedical sensing applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • PVBC microparticles for benzylation of Py 2 TTz molecule to prepare MNP reactor template. • PyTT usage as reducing agent for Ag+, Au3+, Pt2+ metal cations. • AgNP decorated Py 2 TTz-PVBC microparticles as hybrid catalyst for p-nitrophenol reduction. 2,5-di(pyridin-4-yl)thiazolo[5,4- d ]thiazole (Py 2 TTz) molecule was synthesized and used to modify poly(4-vinyl benzylchloride) microparticles (PVBC-MPs) thanks to its superior interaction with 4-vinyl benzyl chloride monomer containing active –Cl atom. PVBC spherical microparticles were successfully synthesized by suspension polymerization method and they were modified via two different approaches as in-situ and post-modification. Monodispersity of particles via in-situ modification is a challenging approach due to the low solubility of Py 2 TTz. Therefore, post-modification of PVBC microparticles with Py 2 TTz dye was carried out. The particles act as metal nanoreactor in the absence of any reducing agent both at room temperature and 50 °C. The particle morphology was determined with electron microscopies before and after reduction process. Metal nanoparticles (MNP) on MPs were characterized via XRD analysis. Gold, silver and platinum nanoparticles (AuNP, AgNP and PtNP) decorated microparticles were successfully synthesized. According to the ICP-MS results, 25.6% Ag, 24.7% Pt and 0.33% Au were found in the microparticles treated with metal cations. These MNP decorated MPs were used as hybrid heterogeneous catalyst for 4-nitrophenol reduction into 4-aminophenol. The highest catalytic efficiency was obtained with AgNPs decorated MPs as also consistent with the ICP-MS data. The catalytic activities of the MNP decorated MPs were determined with time dependent absorption measurents via UV–Vis spectrophotometer. [ABSTRACT FROM AUTHOR]

The micellization behavior of novel tertiary amine methacrylate-based ABA type triblock copolymers formed by poly[2-(dimethylamino)ethyl methacrylate] [PDMA] middle block and poly[2-(diethylamino)ethyl methacrylate] [PDEA] or poly[2-(diisopropylamino)ethyl methacrylate] [PDPA] side blocks, PDPAm-b-PDMAn-b-PDPAl, and PDEAm-b-PDMAn-b-PDEAlwas investigated. Both types of triblock copolymers were water-soluble and had potential for various applications due to their self-assembled and the bottom-up nanoscale micellar construction. The micellar aggregations of the triblock copolymers in aqueous solutions with varying comonomer ratios, molecular weights, temperatures, and pH values were investigated by small-angle X-ray scattering and dynamic light scattering. Compact micellar aggregations were obtained as 0.5 weight percent solutions at 20–21°C and pH 8.67 to 9.05, and characterized as polydispersed spherical core-shells. One group of triblock copolymer micelles had PDPA-cores with radii from 18 to 21 Å and PDMA-shell thicknesses of 89–105 Å, whereas the other group had PDEA-core spherical micelles with core radii of 60–62 Å and a PDMA-shell thicknesses of 64–66 Å. [ABSTRACT FROM AUTHOR]

[Display omitted] • D-A-D type HPhTT dye as fluorescent chemosensor for multiple analyts. • Optical sensing of Au3+ and Fe3+ ions leading from quenching via PET mechanism. • Anion and base sensitivity in gradual steps resulting from hydrogene bonding and enhanced ICT. • Acidochromic effect in aqueos media resulting with Turn-ON / Turn OFF type sensor. • Linear color change in chromaticity diagram leading concentration or color estimation. Fluorescent 2,5-bis(4-hydroxyphenyl)thiazolo[5,4- d ]thiazole (HPhTT) sensor molecule consisting of thiazolo-thiazole (TTz) binding central unit and phenolic signalling side groups was synthesized with a symmetric structure. The selectivity, sensitivity and reversibility properties of optical sensor towards cations and anions were investigated. TTz unit of the sensor was responsible from cation and proton interactions resulting with fluorescent quenching, while phenolic–OH groups were sensitive to anions with a deprotonation mechanism. The fluorescence quenching in the presence of Au3+ with high selectivity, sensitivity and fast response, making it clear that the sensor was very effective in detecting Au3+. Fluorescent sensor (HPhTT) was also found to be able to recognize AcO-, F- and CN– anions accompanied by obvious UV–vis absorption change and fluorescence switch-on response, and exhibited enhanced intramolecular charge transfer (ICT) strongly depending on the forming conjugated acid after addition of anions. Ratiometric detection and reversible usage of the sensor for AcO-, F- and CN– anions were also possible. The sensor showed remarkable detection ability in a pH > 9 media and it has also been demonstrated that it can be used successfully as a pH sensor in an aqueous media. A colour calculator study using F- anion to estimate colour change, colour purity and colour coordinates under UV light excitation with I 550 /I 444 ratio indicated that HPhTT dye had a promising potential for fluorescent sensor studies. [ABSTRACT FROM AUTHOR]

Abstract: Water-insoluble statistical copolymer was synthesized by copolymerization of methyl methacrylate (MMA) with 2-(dimethylamino)ethyl methacrylate (DMA) via group transfer polymerization (GTP). The DMA residues of the precursor P(MMA-co-DMA) statistical copolymer were then quaternized by reacting with methyl iodide under mild conditions to get well-defined P(MMA-co-QDMA) cationic copolymer. Then, P(MMA-co-QDMA) copolymer was successfully used for surface modification of pencil graphite electrode (PGE) to develop a disposable DNA sensor. This P(MMA-co-QDMA) copolymer modified electrode (q-PGE) was examined for electrochemical monitoring of DNA by using differential pulse voltammetry (DPV) in contrast to unmodified one. The effect of both DNA concentration and sonication time was also examined based on the response of q-PGE. The detection limit was calculated to be 8.06μg/mL at q-PGE. Electrochemical impedance spectroscopy (EIS) was used for the characterization of the surface modification of q-PGE and consequently, the results were found to be in good agreement with the voltammetric measurements. [Copyright &y& Elsevier]

Various experimental methods (XRD, FTIR, SAXS, DLS and SEM) were used to investigate structures of the silk samples weaved by spiders in Turkey. Silk samples were collected from the natural habitats belonging to the spider species (i.e., Near Salt Lake/Şereflikoçhisar, İvriz Dam/Ereğli-Konya, Karataş Lake/Burdur and several locations in Black Sea Region of Turkey). Among all collected species, Araneidae (Araneus angulatus, Argiope bruennichi, Argiope lobata, Larinoides cornutus), Eresidae (Eresus cinnaberinus), Agelenidae (Agelena labyrinthica), Oecobidae (Uroctea durandi), Miturgidae (Cheiracanthium erraticum), Salticidae (Heliophanus flavipes, Philaeus chrysops), Theridiidae (Steatoda paykulliana) and Gnaphosidae were found significant amongst other spider species. Structural differences and similarities of these species were reported. Diameter range of draglines, inter crystallite distance of nano-size structures, mean size range of nano-structure aggregations, crystallite size range, information about protein content were obtained. The mechanical properties of some silk fibers were also investigated. [ABSTRACT FROM AUTHOR]

Abstract: The desorption and subsequent pH-responsive behavior of selectively quaternized poly(2-(dimethylamino)ethyl methacrylate)-block-poly(2-(diethylamino)ethyl methacrylate) (PDMA–PDEA) films at the silica/aqueous solution interface has been characterized. The copolymer films were prepared at pH 9, where micelle-like surface aggregates are spontaneously formed on silica. The subsequent rinse with a copolymer-free electrolyte solution adjusted to pH 9 causes partial desorption of the weakly or non-quaternized copolymers, but negligible desorption for the highly quaternized copolymers. Further rinsing with a pH 4 electrolyte solution results in additional desorption and extension (swelling) of the remaining adsorbed copolymer film normal to the interface. This pH-responsive behavior is reversible for two pH cycles (9–4–9–4) as monitored by both quartz crystal microbalance with dissipation monitoring (QCM-D) and also ζ potential measurements. The magnitude of the pH-responsive behavior depends on the mean degree of quaternization of the PDMA block. Moreover, a combination of contact angle data, ζ potential measurements and in situ atomic force microscopy (AFM) studies indicates that the pH-responsive behavior is influenced not only by the number of cationic binding sites on the adsorbed copolymer chains but also by the adsorbed layer structure. [Copyright &y& Elsevier]

Abstract: The pH-responsive behavior of adsorbed diblock copolymer films of PDMA–PDEA (poly(2-(dimethylamino)ethyl methacrylate)–block–poly(2-(diethylamino)ethyl methacrylate)) on silica has been characterized using a quartz crystal microbalance with dissipation monitoring (QCM-D), an optical reflectometer (OR) and an atomic force microscope (AFM). The copolymer was adsorbed at pH 9 from various copolymer concentrations; QCM-D measurements indicate that the level of desorption when rinsed at pH 9 depends on the initial copolymer concentration. The adsorbed films produced at pH 9 generally have low charge densities; adjusting the solution pH to 4 results in a significant protonation of the constituent copolymers and a related interfacial structural change for the copolymer film. OR studies show no significant change during pH cycling, while QCM-D measurements indicate that the adsorbed mass and dissipation alter dramatically in response to the solution pH. The difference between the QCM-D adsorbed masses and dissipation values at pH 4 and 9 were found to be dependent on the initial copolymer concentration. This is due to differences in the initial conformations within the adsorbed copolymer layers at pH 9. The effect of the PDMA chain length on the pH-responsive behavior has also been studied; both the QCM-D adsorbed mass and dissipation of PDMA54–PDEA24 (shorter PDMA block) at pH 4 and 9 were observed to be greater than those of PDMA9X–PDEA2Y (longer PDMA block). This suggests that the normal extension of the adsorbed PDMA54–PDEA24 copolymer films is more significant than that of the PDMA9X–PDEA2Y films on silica. [Copyright &y& Elsevier]

• Liposome-based microgels as novel drug release system for 5-FU cancer drug molecule. • Sustained drug release of 5-FU loaded microgels being noncytotoxic on L929 cell line. • 5-FU loaded lower toxic liposome-microgel has a good promising effect on MCF-7 cells. • These systems may provide new opportunities in in-vivo drug release approaches. Micro/nano-sized particles provide a control on optimization of the therapeutic index of cancer drugs. This study reports successful modification of the multi-responsive microgels based on a water-soluble 2-(N -morpholino)ethyl methacrylate (MEMA) monomer for sustained drug delivery of 5-fluorouracil (5-FU). PMEMA microgel hosting 5-FU loaded 1,2-dipalmitoyl- sn -glycero-3-phosphocholine (DPPC) liposome system was successfully prepared. DPPC liposome-based PMEMA microgel system was also studied in in-vitro studies as a drug carrier and controlled drug release system in phosphate buffer solution and normal saline solution. The release of 5-FU from both PMEMA microgel and liposome-based PMEMA microgel systems was analyzed using HPLC with ultraviolet spectrophotometer detector (λ 266 nm). The cytotoxic assays of liposome-based microgel and 5-FU loaded liposome-based microgel systems were investigated using L929 and MCF-7 which are mouse fibroblast cell line and breast cancer cell line, respectively. In conclusion, PEGylated PMEMA microgel and liposome-based PEGylated PMEMA microgel system provided long-time sustained drug release of 5-FU. It has been observed that the 5-FU release from PEGylated PMEMA system was faster than that of DPPC liposome-based microgel system. Additionally, 5-FU release from DPPC liposome-based microgel system was determined to be very effective on MCF-7 breast cancer cell line, which indicates great potential for further in-vivo studies. [ABSTRACT FROM AUTHOR]