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Poly (acrylamide/vinylsulfonic acid) PA/VSA and poly (acrylamide) PA hydrogels were prepared by free radical polymerization in the presence of a crosslinker, to be used as a support for the invertase enzyme. Spectrophotometric, thermal analysis methods, swelling, and diffusion experiments were used for the characterization of hydrogels. SEM images show that the hydrogels have a smooth, homogeneous, highly porous and spongy morphology. The swelling of PA/VSA was higher than that of PA in water. The diffusion of water within the hydrogel was found to be non-Fickian. Invertase was immobilized onto PA and PA/VSA (immobilized invertases named PA-I and PA/VSA-I, respectively). The optimum pH values were found to be; 5.0, 3.0, and 3.0 for free invertase, PA-I, and PA/VSA-I, respectively. The optimum temperature values were 40°C, 50°C, and 60°C for free invertase, PA-I and PA/VSA-I respectively. Michaelis Constant, Km ; for free invertase and PA-I and PA/VSA-I were found to be 11.80, 21.40, and 18.42 mM, respectively. Maximum reaction rate; Vmax value for free invertase and PA-I and PA/VSA-I were found to be 7.46 μmol min-1 , 5.91 μmol min-1 , and 6.35 μmol min-1 , respectively. PA/VSA-I showed excellent thermal, operational, storage, and pH stability.

New polymer nanocomposites containing silver nanoparticles, stabilized by hydrophilic copolymers of 1-vinyl-1,2,4-triazole with vinylsulfonic acid sodium salt of different composition, were synthesized. Nanocomposites formation was carried out by the method of chemical reduction of silver ions by sodium borohydride in an aqueous medium in the presence of co-polymer. It was established according to the results of transmission electron microscopy that obtained polymer nanocomposites consist of isolated silver nanoparticles of predominantly spherical shape with a diameter from 2 to 16 nm. It was found that composition of the stabilizing polymer matrix controls such nanocomposites parameters as the polydispersity index of nanoparticles (Dw/Dn = 1.44−1.34), hydrodynamic radii of macrocoils (266−1118 nm), and zeta potential (from −35.0 to −74.8 mV).

Alginate–acrylic acid–vinylsulfonic acid/functionalized multiwalled carbon nanotubes (Alg–AA–VSA/f-MWCNTs) composite was prepared by gamma radiation as initiator the graft copolymerization of VSA and AA on Alg onto f-MWCNTs surface matching to template polymerization technique. The optimum synthesis conditions of the nanocomposite are 2.5 wt% Alg, 40 wt% comonomer, 0.5 wt% f-MWCNTs, 0.8 wt% NMBA, AA/VSA monomer composition of 70/30 wt%, and 25 kGy absorbed dose. The structure of the nanocomposite was analyzed using FTIR, TGA, SEM, and XRD. The adsorption of Co(II) radionuclide was applied by batch technique. The kinetic, isotherm, and thermodynamic data of the adsorption of Co(II) deduced that the adsorption followed the second-order model and Langmuir model and became favorable at a low temperature, respectively. Maximum capacity of Co(II) adsorption was 306.399 mg/g.

The synthesis and characterization of six homo- and heteroleptic coordination polymers and oxido clusters of bismuth(III) vinylsulfonates are reported. The solvent-mediated reaction of BiPh3 and vinylsulfonic acid in ethanol produces [{Ph2 Bi(O3 SCH=CH2 )}n ] (1), which crystallizes as a one-dimensional coordination polymer as a result of bridging sulfonato ligands accompanied by intermolecular Bi⋅⋅⋅ π(arene) London dispersion interactions. In solution, compound 1 equilibrates to give [{PhBi(O3 SCH=CH2 )2 }n ] (2) and BiPh3 . Compound 2 is obtained as a single product by the reaction of BiPh3 with vinylsulfonic acid in acetonitrile and crystallizes as a one-dimensional coordination polymer. The homoleptic vinylsulfonate [{Bi(O3 SCH=CH2 )3 }n ] (3) was isolated as a two-dimensional coordination polymer, which is quite moisture sensitive, but did not provide a distinct polynuclear bismuth oxido cluster upon hydrolysis. However, by treatment of [Bi6 O4 (OH)4 (NO3 )6 ]⋅H2 O or [Bi38 O45 (OMc)24 (dmso)9 (H2 O)2 ]⋅2 DMSO⋅5 H2 O (OMc=methacrylate) with vinylsulfonic acid, such a cluster, namely, [Bi9 O7 (OH)(O3 SCH=CH2 )11 (dmso)11 ](O3 SCH=CH2 )⋅3 DMSO (4), is available as the main product. Starting from the hexanuclear bismuth oxido nitrate, another cluster, [Bi38 O45 (NO3 )8 (O3 SCH=CH2 )14 (dmso)18 ](O3 SCH=CH2 )2 ⋅2 DMSO (5), was observed as a co-crystallizing side product, which upon further hydrolysis afforded [Bi38 O45 (NO3 )6 (OH)4 (O3 SCH=CH2 )12 (dmso)23 (H2 O)2 ](O3 SCH=CH2 )2 ⋅2 H2 O (6).

To improve the effectiveness of cancer treatment, this study aimed to develop biodegradable microspheres and to combine chemotherapy and radiotherapy via transcatheter arterial embolization/chemoembolization (TAE/TACE) with local radiation therapy for the slow release of chemotherapeutic agents. Microparticles were prepared by double emulsification using a biodegradable and biocompatible polymer Poly(D,l-lactide-co-glycolide) (PLGA). Since the microspheres contain a water-soluble Poly(vinylsulfonic acid) (PVSA) solution, the functional groups of this polymer dissociate into −SO3– in water. The positively charged doxorubicin can be loaded into beads, ensuring slow release. After 188Retin colloids were added into the microspheres, TACE was performed in a rat hepatocellular carcinoma model. Single photon emission computed tomography/computed tomography imaging and biodistribution analyses showed that the microspheres were still in the liver after 72 h. During 4 weeks of observation, ultrasound images showed ...

Polyetheretherketone (PEEK) has the potential to replace traditional metallic materials as an orthopedic and dental implant because its elastic modulus is similar to natural bone, although its intrinsic bioinertness hampers its clinical application. In this study, sulfonate groups were introduced onto the PEEK surface through a single-step ultraviolet-initiated graft polymerization of vinylsulfonic acid sodium. Diffuse reflectance Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses confirmed the successful attachment of sulfonate groups to the PEEK surfaces. A decreased angle of contact suggested there was an increase in hydrophilicity as a result of endowing the PEEK surface with sulfonate groups. Atomic force microscopy revealed there to be no significant changes in surface topology and roughness as a result of the surface modification. In vitro cell adhesion, viability assay, alkaline phosphatase activity and extracellular matrix mineralization analyses, and real-time ...

Zwitterion polymers have anti-fouling properties; therefore, grafting new zwitterions to surfaces, particularly as hydrogels, is one of the leading research directions for preventing fouling. Specifically, polyampholytes, polymers of random mixed charged subunits with a net-electric charge, offer a synthetically easy alternative for studying new zwitterions with a broad spectrum of charged moieties. Here, a novel polyampholyte hydrogel was grafted onto the surface of polyethersulfone membrane by copolymerizing a mixture of vinylsulfonic acid (VSA) and [2-(methacryloyloxy)ethyl]trimethylammonium chloride (METMAC) as the negatively and positively charged monomers, respectively, using various monomer ratios in the polymerization solution, and with N,N′-methylenebisacrylamide as the crosslinker. The physicochemical, morphological and anti-fouling properties of the modified membranes were systematically investigated. Hydrophilic hydrogels were successfully grafted using monomers at different molar ratios. A thin-film zwitterion hydrogel (∼90 nm) was achieved at a 3:1 [VSA:METMAC] molar ratio in the polymerization solution. Among all examined membranes, the zwitterion polyampholyte-modified membrane demonstrated the lowest adsorption of proteins, humic acid, and sodium alginate. It also had low fouling and high flux recovery following filtration with a protein or with an extracellular polymeric substance solution. These findings suggest that this polyampholyte hydrogel is applicable as a low fouling surface coating.

Facile and clean transformation for synthesizing secondary arylamines through one-pot reductive amination of aniline has been catalyzed by supported nickel nanocluster and poly(vinylsulfonic acid) into mesoporous carbon CMK-3 (Ni/PVSA/CMK-3) as a bi-functional metal/acid heterogeneous catalyst. Vinylsulfonic acid has been polymerized in CMK-3 pores by an in situ method. The process was run in the presence of NaBH4 at room temperature, in a short reaction time, and without secondary product. Various characterization techniques, including FT-IR, XRD, TG, BET, SEM, TEM, DRS-UV, and AAS were employed to disclose the physical and chemical properties of the catalyst. Reaction results demonstrate that the optimized Ni/PVSA/CMK-3 catalyst shows comparable catalytic performance thanks to the nickel metals and the acidic nature of polymer incorporated in mesoporous channels of CMK-3. Besides being eco-friendly (using water as solvent), the method has several advantages such as simple work-up procedure and moderate to high-yield. This catalyst was easily filtered and reused without noticeable loss of activity after 10 runs.

A novel organic-inorganic hybrid material with the core-shell framework was prepared by modifying the poly(vinylsulfonic acid, sodium salt) (PSS) on vinyl functionalized silica nanoparticles (VSNs) via the free radical polymerization. SNs with different contents of PSS were prepared and the structures were carefully characterized. The hybrid material could enhance the durability of PSS under high humidity environment. Meanwhile, the SNs skeleton provides interstitial channels in the PSS@SNs films, which are available for water molecules transport. The PSS coated SNs (PSS@SNs) films were formed by drop-coating and their sensing properties were investigated. The impedance of the optimal humidity sensor changed more than four orders of magnitude over the relative humidity range of 33–95%, with good linearity under semi-logarithm scale (R2 = 0.950) and a small humidity hysteresis of 2% RH. The obtained sensor also showed rapid response to humidity change (the response and recovery time were 2 and 65 s, respectively). Finally, the resultant sensor was explored for respiratory rate monitoring.

Alginate-based composites with appropriate characteristics as polymer-electrolyte membranes (PEMs) were prepared by blending the polysaccharide with poly(vinylsulfonic acid), reinforcing with inorganic fillers such as TiO2 or NiFe2O4, and cross-linking with Ca2+ or Ba2+. The obtained membranes were studied from the structural and morphological points of view by FT-IR spectroscopy and scanning electron microscopy (SEM), respectively. Likewise, the materials were subjected to typical tests usually employed for PEMs evaluation, such as water-uptake properties, endurance in oxidative environment (Fenton reagent) and acidic solution (pH = 3), as well as mechanical and thermal behavior. The proton conductivity performances were evaluated by means of dielectric spectroscopy. The water uptake and chemical stability of the membranes were improved by the inorganic filler presence. The mechanical and thermal analysis proved the preparation of resistant membranes. The conductivity value of 3.0 × 10−4 S/cm obtained for calcium cross-linked membrane containing TiO2 was of only one order of magnitude lower as compared to Nafion. However, this can be offset by expected lower cost and the benign nature of polysaccharide-based composite membranes.

The free-radical copolymerization of 1-vinyl-1,2,4-triazole with vinylsulfonic acid sodium salt was conducted. New thermally stable functional water-soluble copolymers of various composition were synthesized. The structure and properties of the obtained copolymers were confirmed by IR, 1H NMR spectroscopy, and thermogravimetric methods. It was found that 1-vinyl-1,2,4-triazole has higher reactivity than sodium vinylsulfonate. TGA and DSC show that the produced copolymers are stable when heated to 260 °C.

Here I report on the identification of 1-mercaptoethanesulfonic acid (1-MES), an analogue of 2-mercaptoethanesulfonic acid (coenzyme M, HSCoM). 1-MES and HSCoM were both present in the growth media of eight different methanogens at concentrations ranging from ∼1 to 100 μM. In an effort to determine a chemical origin of 1-MES, several plausible chemical routes were examined each assuming that HSCoM was the precursor. In all examined routes, no 1-MES was formed. However, 1-MES was formed when a solution of vinylsulfonic acid and sulfide were exposed to ultraviolet light. On the basis of these results, I conclude 1-MES is formed enzymatically. This was confirmed by growing a culture of Methanococcus maripaludis S2 in the presence of [1,1′,2,2′-2H4]HSCoM and measuring the incorporation of deuterium into 1-MES. 1-MES incorporated three of the four deuteriums from the fed HSCoM. This result is consistent with the abstraction of a C-2 deuterium of the HSCoM, likely by a 5′-dAdoCH2• radical, followed by a radical...

Photografting coloration of wool was carried out under UV-LED irradiation at room temperature using aqueous vinylsulfone dye solution containing vinylsulfonic acid as a comonomer. UV-LED irradiation of the 395 nm emission is more energy efficient, less damaging to the dyes, and much safer to human eyes compared with polychromatic mercury UV lamps. However, in case of the UV-LED lamps, the wool needs to be photo-oxidized either by UV/ozone or polychromatic UV irradiation before the dye photografting. The surface treatments increased the sulfur and oxygen contents in the modified wool surfaces. While the optimally photografted wool fabrics under the UV-LED lamp yielded a K/S value of 9.9, the K/S of the grafted wool increased to 25.2 and 13.6 after the UV/Ozone or polychromatic UV preoxidation at UV energies of 10.6 J/cm2 and 25 J/cm2 respectively. The color fastness properties of the photografted fabrics were far better than with those of the conventionally reactive-dyed fabrics, implying that the high-molecular-weight photografted dyes seemed to be more durable than the low-molecular dyes.

Emulsion templating has emerged as a cutting-edge technique to prepare a wide array of porous polymer–metal nanocomposites with intriguing properties. Using this strategy, we set out to prepare novel hierarchically porous poly(vinylsulfonic acid) beads, which were then used for the in situ production of silver nanoparticles to obtain poly(vinylsulfonic acid)–Ag nanocomposite beads via a facile approach. Owing to their multimodal macro-meso-/microporosity that accounts for their decent BET surface areas (170.75–197.74 m2/g) and easier mass diffusion and transport together with the synergistic benefits of very small silver nanoparticles (down to ∼3.77 nm), the nanocomposite beads are found effective to remove Hg(II) and RhB and to kill Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. The adsorption capacities (167.98–190.58 mg/g) of these materials for Hg(II) surpass some recently reported benchmark materials. The larger size (1.56 ± 0.20–1.50 ± 0.14 mm) of the beads that...

Given the vital role of water in life it is paramount to thrive and succeed in areas that look to clean and prevent further contamination in water bodies. Triclosan (TCS) is present in most of our day-to-day products and if left unchecked it can lead to long-term significant problems due to its many inauspicious effects in both human and animal health. Thus arose the need to develop sensors to detect and possibly remove TCS for aqueous solutions. This work was rooted on this premise and sensors based on LbL polyectrolyte thin-films were developed, such as poly(allylamine hydrochloride) (PAH) and poly(vinylsulfonic acid, sodium salt) (PVS), namely (PAH/PVS) 10 and (PAH/PVS)/PAH 10 . The goal of this work was to analyze the amount of TCS adsorbed onto reused (PAH/PVS) 10 and (PAH/PVS)/PAH 10 LbL thin-films when immersed in TCS aqueous solutions with decreasing pH. It was demonstrated that sensors with an outer layer of PAH led to a significantly better TCS molecules adsorption (removal). Additionally, sensors composed of (PAH/PVS) 10 presented higher sensibility in discriminating TCS solutions with concentrations between 10−5M and 10−8M, using impedance spectroscopy.

A low friction coefficient and high bearing capacity can improve the service life of implants in the human body. In this study, the surface performance was improved by coupling the structure with the material. The bionic structure was obtained on the titanium alloy (Ti6Al4V) surface by chemical etching. The mechanical properties of Ti6Al4V with bionic structure were investigated by tribological experiments with different stresses. An interesting phenomenon was found that the friction coefficient of etched surface decreased with the increase of the stress, indicating that bionic structure can effectively improve the stability of Ti6Al4V surface bearing capacity. A poly (vinylsulfonic acid) sodium (PVSNa) coating was further fabricated on etched Ti6Al4V to obtain low friction. During the sliding process, PVSNA molecules were continuously added from the bionic structure to the surface through friction force for lubrication. The synergistic regulation of bionic structure and PVSNa coating made Ti6Al4V surface obtain low friction and high bearing capacity stability. This study can serve as a guide for the design of low friction and high bearing capacity stability.

Arene diazonium salts undergo Matsuda–Heck reactions with vinylsulfonates and -sulfonamides to give styrylsulfonic acid derivatives in high to excellent yields and with high to excellent selectivities. By quantifying the evolution of nitrogen over time in a gas-meter apparatus, the reactivities of ethylvinylsulfonate and the benchmark olefin methyl acrylate were compared for an electron-rich and an -deficient arene diazonium salt. Tertiary sulfonamides react in Matsuda–Heck couplings with high conversions, but require long reaction times, which prevents the determination of kinetic data through the measurement of nitrogen evolution. Secondary sulfonamides were found to be unreactive. From these results, the following order of reactivity could be deduced: H2C=CHCO2Me > H2C=CHSO2OEt > H2C=CHSO2N(Me)Bn >> H2C=CHSO2NHBn. Through the Matsuda–Heck coupling of 5-indolyldiazonium salt and a tertiary vinylsulfonamide, the synthesis of the C-5-substituted indole part of the antimigraine drug naratriptan was accomplished in high yield.

A post-photochemical cross-linking strategy was successfully demonstrated to enhance the stability of polyelectrolyte poly(allylamine hydrochloride)(PAH)/poly(vinylsulfonic acid sodium salt)(PVS) multilayers. Conventional polyelectrolyte multilayers of PAH/PVS are usually fabricated through electrostatic layer-by-layer(LbL) assembly, resulting in poor stability, especially in basic solutions, which leads to the urgent demand for converting weak electrostatic interactions into covalent bonds to enhance the stability of the multilayers. This stability problem has been ultimately addressed by post-infiltrating a photosensitive cross-linking agent, 4,4′-diazostilbene-2,2′-disulfonic acid disodium salt(DAS), into the LbL assembled films to initiate the photochemical reaction to cross-link the multilayers. The obviously improved stability of the photo-cross-linked multilayers was demonstrated through experiments with basic solution treatments. Compared to the complete decomposition of uncross-linked multilayers in basic solution, over 74.4% of the covalently cross-linked multilayers were retained under the same conditions, even after a longer duration of basic solution treatment.

In the paper a homogeneous anion exchange membrane was modified by electrodeposition of the polyelectrolyte containing different functional groups such as poly(sodium 4-styrene sulfonate) (PSS), poly(vinylsulfonic acid, sodium salt) (PVS) and poly(sodium acrylate) (PAAS), respectively, to improve its antifouling performance in electrodialysis. The surface morphology and electrical resistance of modified membranes were nearly no obvious changes, but their contact angles all increased by 10°. The zeta potential results indicated that the polyelectrolyte PVS with sulfonic group but without benzene ring was more favorable to increase the negative charge density of modified membrane. After fouling experiments for sodium dodecylbenzene sulfonate (SDBS), the contact angle and SEM analyses indicated that the antifouling performance of all the modified membranes was significantly enhanced; moreover, PVS was the most suitable for improving the antifouling performance of anion exchange membrane among the polyelectrolytes. The effect of various functional groups contained in different polyelectrolytes on the antifouling performance of modified membranes was analyzed further to reveal the antifouling mechanism of modified membranes for SDBS. It was also confirmed that the negative effect of the polyelectrolyte layer electrodeposited on the membrane surface on electrodialysis performance could be ignored by measuring the conductivity change of the dilute solution.

Owed to their reversible diol-binding ability, phenylboronic acid (BA) derivatives have gained considerable interest for the development of saccharide sensors and drug delivery systems. In particular, BA-containing polymers have been used for the realization of sugar-responsive layer-by-layer (LbL) films. Herein, a LbL system based on cationic BA-homopolymers (PBA) is presented, and its subsequent sugar-induced disassembly is described. The BA-linear polymers (PBA) were intercalated with poly(vinylsulfonic acid, sodium salt) to form (PBA/PVS)n film assemblies. Different orientations of the boronic acid substituent (ortho-, meta-, and para-) in the PBA polymer were investigated for their influence on the LbL assembly. The rate of disassembly in the presence of glucose or fructose was analyzed by UV–vis spectroscopy. Additionally, the PVS component was replaced with an anionic fluorophore, pyranine (PYR), which allowed the assembly and disassembly to be monitored by fluorescence.

Polyaniline (PANI) is an intrinsically conductive polymer used in various applications, including drug delivery, photovoltaic cells, plastic batteries, display devices, microelectronics, chemically modified electrodes, corrosion protection, and polymer light-emitting diode (PLED) displays due to its specific properties like high chemical and thermal stability, good electrical conductivity, etc. Generally, it is prepared using chemical methods, but these methods have shown some drawbacks, such as harsh synthesis conditions, as they are carried out in acidic media using high amounts of oxidizing agents. During the last few decades, enzymatic catalytic synthesized PANI has attracted attention, as it is synthesized under milder conditions. Various enzymes, such as horseradish peroxidase, laccase, soybean peroxidase, etc., have been used for the fabrication of PANI. These enzymes are extracted from noncontaminant renewable sources. Enzymatic polymerization of aniline has also been done using polyelectrolyte templates, such as poly(4-sodium styrene sulfonate) (SPS), poly(vinylsulfonic acid, sodium salt) (PVS) polyanions, AOT (sodium bis(2-ethylhexyl) sulfosuccinate) vesicles, deoxyribonucleic acid (DNA), etc. Templates help to provide a lower pH condition, which promotes para-directed or head-to-tail coupling and also serves to emulsify the monomer, which leads to the formation of a water-soluble conducting polymer. The addition or presence of blocking or side groups increase the processability and affect the properties. The processability of PANI is enhanced by the use of various groups, usually by modifying the polymer chain with various rings or N-substituents. Other parameters that help in the polymerization reaction are the origin of the enzyme, reactant size, number of steps, template, pH, class of enzyme, etc.

The layer-by-layer method is an attractive technique for preparing ultrathin nanostructured polyelectrolyte multilayer membranes (PEMMs) with tailored composition and tunable properties. This paper investigates the optimization of the membrane preparation to render it more feasible from a practical view point. PEMMs were prepared with minimal number of bilayers and rinsing steps for two polyion combinations: poly(diallyldimethylammonium chloride) with poly (vinylsulfonic acid sodium salt) and the same cation with poly(sodium 4-styrenesulfonate). Three bilayers proved optimal for SRNF applications. The commonly applied rinsing process turned out to be non-essential. In addition, two minutes dipping time per deposition step already proved sufficient for defect-free SRNF membrane preparation. Thus, the build-up protocol for PEMMs was overall reduced to a 6-step coating procedure taking 12 min without compromising the SRNF properties, in contrast to the previously reported 20–80 steps which required upto 7 h. Therefore, the ‘up-scaling’ potential of this type of membrane is significantly increased and potential production costs reduced.

Radical polymers are an emerging class of non-conjugated, charge-conducting macromolecules that are capable of transporting charge through localized oxidation–reduction (redox) reactions that occur at the stable radical groups present as the pendant groups of the macromolecular chains. The chemical nature and oxidation state of these pendant radical groups are critical to the charge transporting abilities of radical polymers in the solid state. To date, however, the control of this chemistry has been limited to external oxidizing agents, and the concept of intramolecular dopants has not been explored fully. To this end, we have synthesized poly(2,2,6,6-tetramethylpiperidinyloxy methacrylate)-co-poly(vinylsulfonic acid sodium salt) (PTMA-co-PVS). Then, electron paramagnetic resonance spectroscopy and attenuated total reflectance-Fourier transform infrared spectroscopy are implemented to evaluate the exact chemical nature of the pendant groups as a function of the PVS intramolecular dopants and exposure of the materials to external oxidation reactions. We correlate these changes in pendant group chemistry to charge transport ability, and we establish that the inclusion of a moderate amount of PVS dopants can improve the solid-state hole mobility of the material. Conversely, a large amount of sulfonic acidic dopants can be detrimental to the transport of the polymer relative to the homopolymer PTMA. Therefore, refinement of pendant group chemistry and careful addition of intramolecular dopants can enhance the solid-state transport ability of a radical polymer system. These fundamental principles, in turn, provide a vital foothold by which to optimize the solid-state charge transporting ability of current and next-generation radical polymer designs.

Nanosized luminescent sensors were prepared as reagents for optical sensing and imaging of oxygen using ratiometric emission properties of a two-dye system. Polymeric capsules were fabricated utilizing poly(vinylsulfonic acid) (PVSA)-stabilized vaterite CaCO3 nanoparticles (CCNPs) as sacrificial templates. The buffer and polymeric surfactant requirements of the layer-by-layer (LbL) process were evaluated toward deposition of multilayer coatings and, ultimately, formation of hollow capsules using these interesting materials. CCNPs were found to be more stable in alkaline NaHCO3 buffer after repeated cycles of washing under sonication and resuspension. An intermediate PVSA concentration was required to maximize the loading of oxygen-sensitive porphyrin and oxygen-insensitive fluorescent nanoparticles in the CCNPs while maintaining minimal nanoparticle size. The CCNPs were then coated with polyelectrolyte multilayers and subsequent removal of the CaCO3 core yielded nanocapsules containing dye and fluorescent nanoparticles. The resulting nanocapsules with encapsulated luminophores functioned effectively as oxygen sensors with a quenching response of 89.28 ± 2.59%, and O2 (S = 1/2) = 20.91 μM of dissolved oxygen.

An efficient method for the removal of methylene blue dye (MB) (cationic-dye) from aqueous solution under alkaline conditions was explored, by synthesizing and utilizing suitable pH sensitive poly (acrylic acid-co-vinylsulfonic acid) hydrogel (PAAVSA). The hydrogel was synthesized by free radical polymerization reaction using optimum ratio of the acrylic acid and vinylsulfonic acid monomers. The functional groups present in PAAVSA (i.e. COO− and SO3− groups) have strong affinity with positively charged (cationic) dye molecule, enabling absorption and trapping of cationic dyes from aqueous solution. Synthesized PAAVSA was characterized by Raman and Fourier-transform-infrared-spectroscopy techniques, while significant pH response of PAAVSA, was evident through swelling studies, indicating large swelling ratio, ~250, at higher pH values. Field-emission-scanning-electron-microscopy (FESEM) images of the respective freeze-dried PAAVSA samples swelled at different pH, exhibit distinct pH-responsive change in surface morphology of the hydrogel. PAAVSA shows significant efficiency as an adsorbent for the removal of cationic dyes (MB-dye) from aqueous solution at higher pH values (pH 7 and above), along with biocompatibility and excellent reusability, leading to potential application in waste-water treatment. The adsorption kinetics and isotherm analysis indicate that the overall adsorption process was governed by chemisorption through heterogeneous surfaces having different activation energies for adsorption of MB-dye.

The aim of the paper is to study the physico-chemical phenomenon of synthesized graft copolymer (carboxymethylated guar gum-g-vinylsulfonic acid). The reaction optimum conditions for grafting has also been determined by studying the effect of vinylsulfonic acid, hydrogen ion, peroxymonosulphate, glycolic acid concentration and carboxymethylated guar gum along with time and temperature. Experimental results show that maximum grafting has been obtained at 1.8 g dm(-3) concentration of partially carboxymethylated guar gum and 5.3 × 10(-2) mol dm(-3) concentration of vinylsulfonic acid. It has been observed that grafting ratio, add on, conversion, efficiency increase up to 4.0 × 10(-3) mol dm(-3) of hydrogen ion, 4 × 10(-3) mol dm(-3) of glycolic acid, 14 × 10(-3) mol dm(-3) of peroxymonosulphate and 35 °C of temperature. Grafted copolymer has been characterized by FTIR spectroscopy and thermogravimetric analysis. Water swelling, flocculating, metal ion uptake and resistance to biodegradability properties of partially carboxymethylated guar gum-g-vinylsulfonic acid have been determined.

We report the development of a urea biosensor based on a separative field-effect structure containing polyaniline in nanostructured form. Urea is normally produced by the nitrogen metabolism in the body, but its excess is indicative of kidney malfunction. Layer-by-layer (LbL) films of polyaniline in nanostructured form (N-PANI) and poly(vinylsulfonic acid) (PVS) were fabricated in a simple and low-cost way and used as pH-sensitive membranes. Urease was further immobilized on N-PANI by a reticulation process using glutaraldehyde (GA) as a crosslinking agent. The PVS/N-PANI–urease membrane was previously studied as a pH sensor using a junction field-effect transistor (JFET) input operational amplifier as a readout circuit and showed a Nernstian behaviour (∼59 mV/pH) in the 6–8 pH range with a small voltage drift. The analytical curve of the biosensor showed a wide dynamic range of urea detection (0.05–10.0 mM), which covers the usual urea concentration in human blood, indicating that the proposed biosensor can be used in clinical analyses.

A new synthesis procedure for highly crosslinked macroporous amphiphilic N-adamantyl-functionalized mixed-mode acrylamide-based monolithic stationary phases for capillary electrochromatography (CEC) is investigated employing solubilization of the hydrophobic monomer by complexation with a cyclodextrin. N-(1-adamantyl)acrylamide is synthesized and characterized as a hydrophobic monomer forming a water soluble-inclusion complex with statistically methylated-β-cyclodextrin. The stoichiometry, the complex formation constant and the spatial arrangement of the formed complex are determined. Mixed-mode monolithic stationary phases are synthesized by in situ free radical copolymerization of cyclodextrin-solubilized N-adamantyl acrylamide, a water soluble crosslinker (piperazinediacrylamide), a hydrophilic monomer (methacrylamide), and a negatively charged monomer (vinylsulfonic acid) in aqueous medium in bind silane-pretreated fused silica capillaries. The synthesized monolithic stationary phases are amphiphilic and can be employed in the reversed- and in the normal-phase mode (depending on the composition of the mobile phase), which is demonstrated with polar and non-polar analytes. Observations made with polar analytes and polar mobile phase can only be explained by a mixed-mode retention mechanism. The influence of the total monomer concentration (%T) on the chromatographic properties, the electroosmotic mobility, and on the specific permeability is investigated. With a homologues series of alkylphenones it is confirmed that the hydrophobicity (methylene selectivity) of the stationary phase increases with increasing mass fraction of N-(1-adamantyl)acrylamide in the synthesis mixture.

‘Self-doping’ inspired high-density redox copolymers were designed and prepared via free radical copolymerization of 2,2,6,6-tetramethyl-4-piperidyl methacrylate and vinylsulfonic acid (VSA) with a view to preventing a change in salt concentration during the one-electron oxidation of the nitroxide radicals to N-oxoammonium cations in a polymer layer. A copolymer composition of TEMPO–sulfonate anionic group = 1/1 for density-maximized charge neutralization was achieved by controlling the feed ratio of the copolymerization. The formation of copolymers was evidenced by 2D nuclear Overhauser enhanced spectroscopy (NOESY) and diffusion ordered spectroscopy (DOSY) NMR. Poly(TEMPO methacrylate-stat-VSA) was considered to have the alternating tendency due to the acid–base interaction in the comonomers, which were supported not only by the single crystal structure of the 2,2,6,6-tetramethyl-4-piperidyl methacrylate and VSA complex, but also by the 1H–1H correlation in NOE signals. In an aqueous electrolyte with 0.5 M NaCl, the copolymer electrode showed a redox response near 0.66 V (vs. Ag/AgCl), and the excellent cycle performance during 1000 cycles. During the one-electron oxidation of the nitroxide radical, anionic sulfonate groups led to charge compensation of the N-oxoammonium cation. Consequently, the copolymer electrode exhibited the cation migration, which was evidenced by mass-transfer analysis using an electrochemical quartz crystal microbalance (EQCM) technique. The copolymer could be applied as an aqueous electrolyte-type organic rechargeable device. Moreover, this design proposes the ultimate principle toward the strategy of maximizing energy density in organic charge storage devices.

With the aim to improve the understanding of morphology and efficiency properties, we investigate in this series the impact of the complex formation constant of the hydrophobic monomer with respect to statistically methylated-β-cyclodextrin (Me-β-CD) on the electrochromatographic properties of highly crosslinked amphiphilic mixed-mode acrylamide-based monolithic stationary phases. Based on our previous work on amphiphilic mixed-mode monolithic stationary phases for capillary electrochromatography (CEC) using N-(1-adamantyl)acrylamide (Ad-AAm) as hydrophobic monomer that forms an extremely strong water-soluble inclusion complex with Me-β-CD, we now selected N-tert-butylacrylamide (NTBA) as hydrophobic monomer forming an inclusion complex with Me-β-CD with a much lower value of the formation constant. Mixed-mode monolithic stationary phases are synthesized by in-situ free radical copolymerization of cyclodextrin-solubilized N-tert-butylacrylamide, a water soluble crosslinker (piperazinediacrylamide), a hydrophilic neutral monomer (methacrylamide), and a negatively charged monomer (vinylsulfonic acid) in aqueous medium in bind silane pre-treated fused silica capillaries. The synthesized monolithic stationary phases have both hydrophobic and hydrophilic moieties and can be employed in the reversed-phase mode, in the normal-phase mode, in a mixed-mode or in the hydrophilic interaction liquid chromatography (HILIC) mode (depending on the composition of the mobile phase and on the properties of the solute). Morphology and retention properties of this new type of stationary phase are compared to those reported in our previous series. With a homologues series of alkylphenones it is confirmed that the hydrophobicity (methylene selectivity αmeth) of the stationary phase is strongly dependent on the type of hydrophobic monomer employed. The studies reveal a significant influence of the formation constant of the involved host-guest inclusion complex on the morphology (i.e., the domain size) of the produced monoliths.

A series of sulfoethyl locust bean gum derivatives with a degree of substitution (DS) ranging from 0.05 to 0.33 was prepared by etherification of locust bean gum with vinylsulfonic acid sodium salt in alkaline 2-propanol suspension. The derivatives were characterized by means of FT-IR and elemental analysis, and evaluated for laundry anti-redeposition performance, alone and in systems with mannanase and/or cellulase enzymes. Optimum anti-redeposition performance was observed at degrees of substitution of around 0.15. Mannanase was found to have a negative effect on sulfoethyl locust bean gum derivatives' performance although a system comprising sulfoethyl locust bean gum derivative and cellulase was found to be complementary.

The solubility of the hen egg-white lysozyme (HEWL) in aqueous solutions at pH 4.5 at various polyelectrolyte concentrations was first measured by a spectroscopical method from (278.15 to 298.15) K under atmospheric pressure. The employed polyelectrolytes were cationic polyacrylamide (CPAM), poly(ethylene imine) (PEI), poly(dimethyldiallylammonium chloride) (PDDA), poly(sodium styrene sulfonate) (PSS), and poly(vinylsulfonic acid, sodium salt) (PVS). The enthalpy and entropy of dissolution have been calculated, and the sol–gel transition has been discussed as well.

Proton-conducting polyelectrolytes were prepared by densely grafting novel sulfonic acid polymers, poly(styrenesulfamide acid) (PSA) and poly(vinylsulfonic acid) (PVS), on the azo-initiator-modified poly(ethersulfone) (PSU). The grafted PSUs provided both a high ion-exchange capacity (IEC) and a good membrane formability. The proton-conductivities of the PSA-g-PSU and PVS-g-PSU membranes were 8.2 and 21 mS cm−1, respectively, at 90°C under a hydrated condition, and 4.1 and 1.7 mS cm−1, respectively, at 150°C under a nonhumidified condition. The latter conductivities were significantly higher than that of Nafion® 117 (0.03 mS cm−1 at 150°C), which was ascribed to both the strong acidity of the graft chains even under the water-free state and the high IEC of the densely grafted membrane. They remained constant for over 1 week at 150°C. Copyright © 2011 John Wiley & Sons, Ltd.

Homopolymers containing sulfonic ester side groups were synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization utilizing benzyl dithiobenzoate, cumyl dithiobenzoate, and 4-cyano-4-((thiobenzoyl)sulfanyl)pentanoic acid as chain transfer agents. Likewise diblock copolymers containing poly(styrene), poly(octylstyrene) and poly(pentafluorostyrene) as the second block were synthesized. Additionally, nitroxide mediated polymerization (NMP) was investigated for the synthesis of a homopolymer as well as for a diblock copolymer. Furthermore, the post-polymerization functionalization with various amines to yield the respective sulfonamides was conducted. The conversion was analyzed by 1H NMR spectroscopy, 19F NMR spectroscopy and FT-IR spectroscopy and in many cases a very high conversion (>96%) was observed. In addition the reaction kinetics of the post-polymerization functionalization of poly(pentafluorophenyl 4-vinylbenzene sulfonate) and the corresponding carboxyl ester poly(pentafluorophenyl 4-vinylbenzoate) were compared by analysis of the reactions by time-resolved 19F NMR spectroscopy. It was found that poly(pentafluorophenyl 4-vinylbenzoate) showed a higher stability towards hydrolysis and a significantly higher reactivity, resulting in complete conversions with different amines.

In this work, polyaniline (PAni), a polycation, and poly (vinylsulfonic acid, sodium salt) (PVSS), a polyanion, were used for preparing multilayer thin films on AA2024 alloy surface using the layer-by-layer growth technique. The corrosion of AA2024 alloy surfaces coated with a number n (n = 0, 1, 5, 8, 10, 15) of multilayered thin films was investigated in 0.1 M NaCl aqueous solutions using potentiodynamic polarization, chronoamperometry and electrochemical impedance spectroscopy (EIS) techniques. These electrochemical tests were conducted at a temperature of (25 ± 2) °C. Surface coated with 08 (PVSS / PAni) bilayers presented greater resistance to corrosion in the chloride containing environment.

Arrays of silicon nanochannels were used to investigate the layer-by-layer (LbL) assembly of nanoparticle-containing multilayers in confined geometries. LbL assembly of poly(vinylsulfonic acid)/titania (PVS/TiO2) and poly(diallyldimethylammonium chloride)/silica (PDAC/SiO2) resulted in conformal, uniform thickness multilayers throughout the high-aspect-ratio nanochannels. These multilayers were also calcinated to form nanoporous coatings within the nanochannels. Confined and unconfined multilayers were compared using scanning electron microscopy (SEM), showing significantly lower bilayer thicknesses when layers were assembled in confined geometries. Deposition was found to essentially stop at a nanochannel gap size of 55 nm for the PVS/TiO2 system and at 210 nm for the PDAC/SiO2 system, even though the channels were not plugged. These results provide further evidence of surface charge-induced depletion of unadsorbed species during LbL assembly, which occurs because of the closely spaced walls with like su...

A new chiral stationary phase based on continuous bed (CB) technology using L-prolinamide as a chiral selector was prepared. Its ability for enantioseparation of amino acids and alpha-hydroxy acids by ligand-exchange CEC was compared with that of a CB containing L-4-hydroxyproline as chiral selector. Preparation was done by a one-step in situ copolyermerization procedure using methacrylamide as monomer, vinylsulfonic acid as charge providing agent and piperazine diacrylamide as crosslinker. L-Prolinamide showed marked enantioselective properties for the separation of amino acids and alpha-hydroxy acids. Furthermore, we show the possibility of simultaneous enantioseparation of amino acids and alpha-hydroxy acids using the CB with L-4-hydroxyproline as chiral selector.

Influence of graft copolymers with different architecture on spontaneous batch crystallization of calcium oxalate was investigated. The series of water-soluble polyethyleneglycol methacrylate-vinylsulfonic acid graft copolymers [(PEG-MA)-co-VS] and homopolymer of vinylsulfonic acid have been made, by radical polymerization, with defined molecular weight and structure. The presence of polymers inhibited the crystal growth of calcium oxalate possibly through adsorption onto the active growth sites for crystal growth due to the charge and hydrophilic effects. The higher inhibition efficiency of vinylsulfonic acid homopolymer is related to the maximum surface charge density due to adsorbed polymer. The homopolymer influenced both the morphology and phase transformation of calcium oxalate crystals. Polyelectrolyte effects were interpreted in terms of the adsorption of inhibitors onto the active growth sites on the crystal surface.

Apatite formation in the living body is an essential requirement for artificial materials to exhibit bone-bonding bioactivity. It has been recently revealed that sulfonic groups trigger apatite nucleation in a body environment. Organic-inorganic hybrids consisting of organic polymers and the sulfonic groups are therefore expected to be useful for preparation of novel bone-repairing materials exhibiting flexibility as well as bioactivity. In the present study, organic-inorganic hybrids were prepared from hydroxyethylmethacrylate (HEMA) in the presence of vinylsulfonic acid sodium salt (VSAS) and calcium chloride (CaCl(2)). The bioactivities of the hybrids were assessed in vitro by examining the apatite formation in simulated body fluid (SBF, Kokubo solution). The hybrids deposited on the apatite after soaking in SBF within 7 days. Tensile strength measurements showed a tendency to increase with increases in VSAS and CaCl(2) content. It was assumed that this phenomenon was attributed to the formation of cross-linking in the hybrids.

Nucleophilic addition of trimethylsilyl esters of hypophosphorus acid to trimethylsilyl ester and diethylamide of vinylsulfonic acid is proposed as convenient methods for the synthesis of new 2-sulfonylethylphosphonites and their derivatives under mild conditions. Also the new functionalized derivatives of these phosphonites, including aminomethyl fragments as well as certain properties of these compounds as important precursors of new organophosphorus-substituted derivatives of ethanesulfonic acid, are presented. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:470–473, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20448

A semi-interpenetrating polymer network (semi-IPN) hydrogel based on kappa-carrageenan (κC) and poly (vinylsulfonic acid, sodium salt) (PVSA) was prepared by graft copolymerization of acrylamide (AAm) using methylenebisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. FTIR spectroscopy was used for confirming the structure of the final product. It was found that the chemical composition of the Semi-IPN hydrogel is equal to the initial homopolymers and monomer feed compositions. The swelling capacity of the hydrogel was shown to be affected by the MBA, APS, and AAm concentration as well as κC/PVSA weight ratio. The swelling behavior of the hydrogel was also investigated in various pHs and salt solutions. Since the highly swelling biopolymer-based hydrogel exhibits low salt-sensitivity, it may be referred to as an anti-salt superabsorbent hydrogel. The swelling kinetics of the superabsorbent hydrogels was studied as well. POLYM. ENG. SCI., 47:1388–1395, 2007. © 2007 Society of Plastics Engineers

A CE method for the determination of the ethanol consumption marker ethyl sulfate (EtS) in human urine was developed. Analysis was performed in negative polarity mode with a background electrolyte composed of 15 mM maleic acid, 1 mM phthalic acid, and 0.05 mM cetyltrimethylammonium bromide (CTAB) at pH 2.5 and indirect UV detection at 220 nm (300 nm reference wavelength). This buffer system provided selective separation conditions for EtS and vinylsulfonic acid, employed as internal standard, from urine matrix components. Sample pretreatment of urine was minimized to a 1:5 dilution with water. The optimized CE method was validated in the range of 5-700 mg/L using seven lots of urine. Intra- and inter-day precision and accuracy values, determined at 5, 60, and 700 mg/L with each lot of urine, fulfilled the requirements according to common guidelines for bioanalytical method validation. The application to forensic urine samples collected at autopsies as well as a successful cross-validation with a LC-MS/MS-based method confirmed the overall validity and real-world suitability of the developed expeditious CE assay (sample throughput 130 per day).

Employing solubilization by complexation with CDs, new mixed-mode monolithic stationary phases for CEC and micro-LC were synthesized. Free radical copolymerization was performed in aqueous solution with a CD-solubilized hydrophobic monomer, a water-soluble crosslinker (piperazinediacrylamide), and a charged monomer (vinylsulfonic acid). Different hydrophobic methacrylate monomers (isobornyl, adamantyl, cyclohexyl, and phenyl methacrylate) were investigated. Chromatographic properties of the synthesized monoliths were studied with aqueous and nonaqueous mobile phases with hydrophobic and polar analytes. Due to the amphiphilic nature of the polymers synthesized, the elution orders obtained correspond to the RP mode and to the normal-phase mode dependent on the polarity of the mobile phase. However, observations made with polar solutes and polar mobile phase can only be explained by a mixed-mode retention mechanism. The influence of the total monomer concentration (%T) on the chromatographic properties and on the specific permeability was elucidated. Run-to-run, day-to-day, and capillary-to-capillary reproducibility of electroosmotic mobility and retention factors were determined. Comparison of retention data with those of a commercial octadecyl silica gel HPLC column reveals that the methylene selectivity of the monolithic capillaries prepared in this study is very similar to that of routinely used octadecyl silica gels.

A new approach is described to produce nanostructured electrocatalytic membranes using a combination of three methods. Using the layer-by-layer technique, PAMAM dendrimers with cobalt hexacyanoferrates-modified gold nanoparticles were alternated with poly(vinylsulfonic acid) layers on ITO (indium tin oxide) electrodes. This film was used as substrate for immobilization of glucose oxidase in the presence of bovine serum albumin and glutaraldehyde as cross-linker. The modified electrode was successfully applied as a biosensor for the amperometric measurement of glucose, using glucose oxidase enzyme, at 0.0 V vs. SCE. Keywords: Layer-by-layer, PAMAM dendrimers, Gold nanoparticles, Enzyme immobilization, Redox mediator, Biosensor

In this work, we exploit the molecular engineering capability of the layer-by-layer (LbL) method to immobilize layers of gold nanoparticles on indium tin oxide (ITO) substrates, which exhibit enhanced charge transfer and may incorporate mediating redox substances. Polyamidoamine (PAMAM generation 4) dendrimers were used as template/stabilizers for Au nanoparticle growth, with PAMAM-Au nanoparticles serving as cationic polyelectrolytes to produce LbL films with poly(vinylsulfonic acid) (PVS). The cyclic voltammetry (CV) of ITO-PVS/PAMAM-Au electrodes in sulfuric acid presented a redox pair attributed to Au surface oxide formation. The maximum kinetics adsorption is first-order, 95% of the current being achieved after only 5 min of adsorption. Electron hopping can be considered as the charge transport mechanism between the PVS/PAMAM-Au layers within the LbL films. This charge transport was faster than that for nonmodified electrodes, shown by employing hexacyanoferrate(III) as the surface reaction marker. Because the enhanced charge transport may be exploited in biosensors requiring redox mediators, we demonstrate the formation of Prussian blue (PB) around the Au nanoparticles as a proof of principle. PAMAM-Au@PB could be easily prepared by electrodeposition, following the ITO-PVS/ PAMAM-Au LbL film preparation procedure. Furthermore, the coverage of Au nanoparticles by PB may be controlled by monitoring the oxidation current.

The goal of this work was to investigate the synergistic effect between the electrostatic and hydrophobic interactions upon the uptake of organic ions with hydrophobic moieties by ion-exchange resins with hydrophobic matrixes. The uptake of neutral amino acids by a macroporous polystyrene-based strongly acidic cation-exchange resin (D001) and two strongly acidic cation-exchange resins (poly(2-acrylamido-2-methyl propanesulfonic acid) and poly(vinylsulfonic acid)) with much less hydrophobic matrixes essentially follow an ion exchange stoichiometry. However, the thermodynamic parameters of the uptakes indicate that besides electrostatic interaction, hydrophobic interaction also contributes to the affinity of the amino acids with hydrophobic side chains for D001. No detectable uptake capacities for the amino acids by D001AM, which was obtained by amidation of the sulfonic acid groups of D001, can be determined. Thus, it is deduced that the hydrophobic interaction alone contributes little to the uptake of these amino acids by D001, of which hydrophobicity is the same with or lower than that of D001AM. These results indicate that synergistic effect exists between the electrostatic and hydrophobic interactions when the two interactions exist in a chelate manner and the hydrophobic interaction contributes to the uptake even if the hydrophobic interaction is so weak that it contributes little to the uptake when it acts alone.

We report on the fabrication of layer-by-layer (LbL) films of PAMAM dendrimers incorporating platinum nanoparticles (Pt-PAMAM) alternated with poly(vinylsulfonic acid) (PVS). Pt-PAMAM structures were obtained via chemical reduction of H2PtCl6 in the presence of PAMAM, using formic acid as reducing agent. An average particle size of 3 nm was estimated using the Scherrer equation with the X-ray diffractograms in multilayer films, which was confirmed with transmission electron microscopy (TEM) for a Pt-PAMAM layer. The formation of Pt nanoparticles was monitored with UV–Vis spectroscopy by measuring the decrease in the band intensity at 375 nm, assigned to the electronic absorption from PtCl62- ions. These LbL films were proven fully tolerant to methanol oxidation for potentials below 1.0 V. As a proof of principle, we show that the electrochemical response for the Pt-PAMAM LbL films is characteristic of platinum, regardless of the presence of methanol in the electrolytic solution. The discovery of a methanol-tolerant electrode in Pt-PAMAM LbL films may represent a major breakthrough for further developments in methanol fuel cells, since methanol crossover through the membrane is one of the most important drawbacks of direct-methanol fuel cells. Keywords: Layer-by-layer, PAMAM dendrimers, Platinum nanoparticles, Methanol fuel cells, Methanol crossover