Methylenebisacrylamide Crosslinker Research Articles

Synthesis and characterization of polyacrylamide-based antibacterial hydrogel nanocomposite

ABSTRACT In this research, the hydrogel nanocomposites based on acryl amide containing penicillin 800, 1200, Ag, and ZnO nanoparticles as wound dressing applications have been studied. In this work, the preparation was done via a reaction of optimal values to produce an antibacterial hydrogel nanocomposite. The hydrogel was obtained in an aqueous medium by using reagents such as acrylamide, potassium persulfate, and methylene bisacrylamide crosslinker, Ag, ZnO nanoparticles, and penicillins and then, the products were dried as white powders. The properties such as swelling rate, pH sensitivity, and high water swelling capacity of the swelling rate study of the hydrogel showed a high absorption rate of water in pH about 3–4. The effect of temperature on the percentage of hydrogel swelling was shown to swell with increasing temperature and the absorption capacity of polyacrylamide hydrogels decreased with increasing NaCl concentration. The chemical structure of hydrogel was confirmed by FTIR spectrum, and the morphology of synthesized hydrogel surfaces was studied via SEM. The antibacterial studies were done in blood, agar, chocolate, and Müller medium via three methods, first on gram-negative bacteria E. coli and Klebsiella, second in urine medium, and third in drug medium. This polymeric blend can be used as a new wound dressing compound.

Novel Hydrolytic Degradable Crosslinked Interpenetrating Polymeric Networks (IPNs): An Efficient Hybrid System to Manage the Controlled Release and Degradation of Misoprostol.

The goal of this study was to make pH-sensitive HPMC/Neocel C19-based interpenetrating polymeric networks (IPNs) that could be used to treat different diseases. An assembled novel carrier system was demonstrated in this study to achieve multiple functions such as drug protection and self-regulated release. Misoprostol (MPT) was incorporated as a model drug in hydroxyl-propyl-methylcellulose (HPMC)- and Neocel C19-based IPNs for controlled release. HPMC- and Neocel C19-based IPNs were fabricated through an aqueous polymerization method by utilizing the polymers HPMC and Neocel C19, the initiator ammonium peroxodisulfate (APS), the crosslinker methylenebisacrylamide (MBA), and the monomer methacrylic acid (MAA). An IPN based on these materials was created using an aqueous polymerization technique. Samples of IPN were analyzed using scanning electron microscopy (SEM), atomic force microscopy (AFM), differential scanning calorimetry (DSC), thermal analysis (TGA), and powder X-ray diffraction (PXRD). The effects of the pH levels 1.2 and 7.4 on these polymeric networks were also studied in vitro and through swelling experiments. We also performed in vivo studies on rabbits using commercial tablets and hydrogels. The thermal stability measured using TGA and DSC for the revised formulation was higher than that of the individual components. Crystallinity was low and amorphousness was high in the polymeric networks, as revealed using powder X-ray diffraction (PXRD). The results from the SEM analysis demonstrated that the surface of the polymeric networks is uneven and porous. Better swelling and in vitro results were achieved at a high pH (7.4), which endorses the pH-responsive characteristics of IPN. Drug release was also increased in 7.4 pH (80% in hours). The pharmacokinetic properties of the drugs showed improvement in our work with hydrogel. The tablet MRT was 13.17 h, which was decreased in the hydrogels, and its AUC was increased from 314.41 ng h/mL to 400.50 ng h/mL in hydrogels. The blood compatibility of the IPN hydrogel was measured using different weights (100 mg, 200 mg, 400 mg, and 600 mg; 5.34%, 12.51%, 20.23%, and 29.37%, respectively). As a result, IPN composed of HPMC and Neocel C19 was successfully synthesized, and it is now possible to use it for the controlled release of MPT.

Temperature and ionic strength modulated responses of modified with viologen derivative electrosensitive microgel

A new electroactive microgel was successfully synthesized. The starting material was a polymer based on N-isopropylacrylamide, sodium acrylate and the N,N'–methylenebisacrylamide crosslinker, which was functionalized with amine derivative of viologen. This two-redox-systems molecule was bound through the amide bond between the viologen amine group and the acrylate carboxylic group. A layer of the electroactive viologen-modified microgel was successfully attached to the Au Quartz-Crystal Microbalance with Dissipation (QCM-D) electrode surface using the “drop on” method. Electrochemical and gravimetric measurements indicated that the thickness of the p(NIPA-SA-V) microgel layer could be altered by three factors: temperature, ionic strength, and potential. Under optimal environmental conditions of 37 °C and low ionic strength, a fast and reversible thickness change from 400 to 250 nm was possible upon application of appropriate potential.

Starch-grafted-poly(acrylic acid)/Pterocladia capillacea–derived activated carbon composite for removal of methylene blue dye from water

Starch-g-poly(acrylic acid)/Pterocladia capillacea–derived activated carbon (St-g-P(AA)/P-AC) composites were prepared via aqueous solution graft copolymerization using starch, acrylic acid, and activated carbon of red alga Pterocladia capillacea (0–10%) with N,N′-methylenebisacrylamide crosslinker and ammonium persulfate (NH4)2S2O8 initiator. Fourier-transform infrared (FTIR) spectroscopy, Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) were used to characterize St-g-P(AA)/P-AC composites. Additionally, St-g-P(AA)/P-AC composites were investigated for methylene blue (MB) dye removal from water. The impact of the beginning concentration of MB dye, temperature, pH, and adsorption time on MB dye removal was examined. The maximum adsorption capacity obtained at pH 8 was 496.29 mg/g at 0.02 mg/L composites dose and 100 mg/L MB dye. The properties of adsorption were studied by the adsorption isotherm, kinetic, and thermodynamic models. The pseudo-first-order and Freundlich isotherm models demonstrated the kinetics and equilibrium adsorptions data, respectively. The maximum monolayer capacity (qm) was 1428.57 mg/g from Langmuir isotherm. Thermodynamic parameters indicated that the MB dye adsorption is exothermic physisorption and spontaneous. The results show that St-g-P(AA)/P-AC composites were effective for MB dye adsorption from water solution and could be recycled.

Preparation of thermoresponsive triclosan poly (N-isopropylacrylamide) nanogels and evaluation of antibacterial efficacy on Cutibacterium acnes

The insufficient effects associated with current treatment regimens require the use of novel therapeutic formulations for acne vulgaris. Consequently, this study was undertaken to develop triclosan nanogels of poly(N-isopropylacrylamide) having a thermoresponsive character prepared by surfactant-free emulsion polymerization in the presence of N,N′ methylenebisacrylamide crosslinker. The particle size, zeta potential, thermal analysis, drug loading, swelling capacity, morphological analysis, ex-vivo diffusion, rheological characterization, and the antibacterial potential against causing C. acnes were evaluated. It was observed that the swelling capacity of nanogel formulations increased when triclosan and ethanol were added. All nanogel formulations performed a viscoelastic behaviour at 25 °C and the elastic modulus G′ was higher at 25 °C compared to 37 °C. The results showed that G′ values increased with increasing concentration of hydrophilic monomers. The encapsulation efficiency was obtained as 47.4% and 63.7%. The antibacterial potency of nanogel formulation against C. acnes surpassed the commercial product used as the positive control. According to the study, TCS nanogels of poly(N-isopropylacrylamide) with size and rheological behaviour were found to be suitable for dermal applications. The potent antibacterial activity in thermoresponsive nanogel formulation could be an alternative to existing conventional formulations in the treatment of acne vulgaris.

Synthesis and Evaluation of Finasteride-Loaded HPMC-Based Nanogels for Transdermal Delivery: A Versatile Nanoscopic Platform.

Herein, we report nanogels comprising diverse feed ratio of polymer hydroxypropyl methylcellulose (HPMC), monomer acrylic acid (AA), and cross-linker methylene bisacrylamide (MBA) fabricated for transdermal delivery of finasteride (FIN). Free radical solution polymerization method with subsequent condensation was employed for the synthesis using ammonium per sulfate (APS) and sodium hydrogen sulfite (SHS) as initiators. Carbopol-940 gel (CG) was formulated as assisting platform to deliver FIN nanogels transdermally. Developed formulations were evaluated by several in vitro, ex vivo, and in vivo parameters such as particle size and charge distribution analysis, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X-ray diffractogram (XRD), rheological testing, in vitro swelling and drug release, and ex vivo skin permeation, irritation, and toxicity assessment. The results endorsed the nanogel formation (117.3 ± 29.113 nm), and the impact of synthesizing method was signified by high yield of nanogels (≈91%). Efficient response for in vitro swelling and FIN release was revealed at pH 5.5 and 7.4. Skin irritation and toxicity assessment ensured the biocompatibility of prepared nanocomposites. On the basis of the results obtained, it can be concluded that the developed nanogels were stable with excellent drug permeation profile across skin.

Synthesis of Cu nanoparticles in a chitosan entrapped copolymer matrix for photocatalytic reduction of textile dye and column adsorption of heavy metal ions from water

AbstractPolymer metal nano‐composites (PMNC) were synthesized by integrating different weight percentage of chitosan (CS), N,N′‐methylenebisacrylamide (MBA) crosslinked poly(acrylic acid‐co‐hydroxyethyl methacrylate) copolymer and Cu nanoparticles (CuNPs). CuNPs were generated in situ during polymerization by reducing CuSO4.5H2O with ascorbic acid. The presence of the CuNPs in the polymer network, functionality, crystallinity, morphology, size distribution of the CuNPs, elemental composition, thermal characteristics, network parameters, pH sensitivity, and strength of the composites was evaluated. The CuNP‐loaded PMNC4 composite prepared with 10:1 acrylic acid : hydroxyethyl methacrylate molar ratio, 1 wt% each of initiator and MBA crosslinker and 4 wt% CS showed a photodegradation efficiency of 64% in 5 h for 50 mg/L methyl violet dye in water. The same polymer showed a rejection of 91.45% and a mass transfer coefficient of 4.14 × 10−5 cm/s for continuous adsorption of 20 mg/L Pb(II) ion in water in a fixed bed of height 22 mm for an inflow rate of 30 ml/min.

Polyacrylamide Gel Scaffold Immobilized with Silver Nanoparticles as SERS Substrates and Catalysts for H2 Generation via Methanolysis of NaBH4

This report discloses the preparation of a series of polyacrylamide materials with unique surface morphology. Polyacrylamide with N,N′-methylenebisacrylamide cross-linking provides reactive sites for the reduction of silver nitrate. The reaction refurbishes the relatively smooth polymer surface to clusters of submicron cubes impregnated with silver nanoparticles (AgNPs) and residual Ag(+1) ions. Subsequent treatment with NaBH4 grows additional silver structures from the AgNPs seeded in the polymer to give an overall morphology reminiscent of the famous great barrier reefs, the namesake of this material─the Great Barrier Gel (GBG). The GBG surface features a high content of active silver nanostructures. The use of GBG as a substrate for surface-enhanced Raman scattering (SERS) and a film catalyst for the methanolysis of NaBH4 demonstrates its versatility. The SERS sensitivity of this material is 10–10 M, or better, as assessed using 4-aminophenyl disulfide. It catalyzes the production of H2 by the methanolysis of NaBH4 without significant loss of activity in an exhaustion test. These methods create an enlarged surface area on the shape-adapting polymer material, chemically and productively, while generating a least amount of chemical waste.

Using surface grafted poly(acrylamide) to simultaneously enhance the tensile strength, tensile modulus, and interfacial adhesion of carbon fibres in epoxy composites

Surface initiated electro-polymerization of acrylamide on carbon fiber with methodically varied amounts of acrylamide monomer and N,N′-methylene bis-acrylamide crosslinker is explored in this study. The effect of the polymer coating on tensile strength, Young's modulus, and interfacial properties of carbon fibre in an epoxy resin was determined. A significant improvement in tensile strength, tensile modulus, and interfacial shear strength (IFSS) across all modified samples was observed, with the most notable improvements to tensile strength, tensile modulus and IFSS being 38%, 15% and 192.5%, respectively. This covalently bound polymer coating provides the best kind of solution for the two most crucial limitations of carbon fibre, with the minimum amount of effort, time, and cost.

Study of swelling behavior of hydrogel nanocomposite based on polydopamine-graphene oxide–polyacrylamide

In this research, the synthesis and swelling behavior of a hydrogel nanocomposite based on acrylamide, graphene oxide and polypopamine have been investigated. The synthesis was performed by grafting with optimal values to achieve a hydrogel with high water absorption swelling capacity. The polymerization reaction was performed in an aqueous medium in the presence of an ammonium persulfate initiator and methylene bisacrylamide crosslinker. The mechanism was proposed for the formation of hydrogels and its structure was confirmed by FTIR, XRD and SEM devices. The results obtained from water absorption and its swelling values in buffer solutions shown the synthesized hydrogels have high absorption capacity.

Micro flow photochemical synthesis of Ca-sensitive fluorescent sensor particles.

Fluorescence probes have widely been used for detecting and imaging Ca2+‐enriched parts of cells but more rarely for quantitative determination of concentrations. In this study we show how this can be achieved by a novel approach using hydrogel particles. In a microfluidic co‐flow arrangement spherical droplets were generated from an aqueous solution of acrylamide, N,N'‐methylenebisacrylamide crosslinker and photoinitiator and subsequently photo‐cured in situ yielding gel particles in a sub millimeter range. These particles were separated, dried under reduced pressure and re‐swollen in water containing Rhod‐5N tri potassium salt as calcium ion selective fluorescence probe. After that the particles were dried again and stored for further investigations. Upon exposure of dried particles to calcium chloride solutions they swell and take up Ca2+‐ions forming a strong fluorescing complex with Rhod‐5N. Thus, fluorescence intensity increases with calcium ion concentration. Up to ca. 0.50 mM the enhancement effect is strong and then becomes considerably weaker. The intensity‐concentration‐dependence is well described by an equation derived from the equilibrium of the formation of a 1:1 Ca2+:Rhod‐5N complex. The particles allow for a fast optical determination of Ca2+‐concentrations up to 0.50 mM in analyte volumes down to below 10 μL.

An Exceptional Broad-Spectrum Nanobiocide for Multimodal and Synergistic Inactivation of Drug-Resistant Bacteria

An Exceptional Broad-Spectrum Nanobiocide for Multimodal and Synergistic Inactivation of Drug-Resistant Bacteria

Synthesis and Characterization of Poly(acrylamide) Hydrogels as pH and Salt Sensitive Material

This work reports the synthesis of poly(acrylamide) hydrogel and its characterization. Hydrogel will be synthesized by a chemical cross-linking method using sodium metabisulfite and potassium persulphate as initiators with crosslinker methylenebisacrylamide. The synthesized hydrogels were examined by FT-IR, SEM and TGA to determine chemical interactions in the polymer network. Moreover, the swelling study explains that hydrogels swelling capacity and it depends on the concentration of the crosslinking agent. The pH, temperature and salt solutions will impact on swelling properties. In acid and base solutions, the swelling ratio order is as follows HCl < CH3COOH < HClO4 < NaOH and the swelling ratio order in salt solutions is as follows: NaCl > CaCl2 > AlCl3.

Ammonium nitrogen adsorption from aqueous solution by poly(sodium acrylate)s: Effect on the amount of crosslinker and initiator

AbstractIn this work, we discuss the ammonium nitrogen adsorption and reusability from aqueous solution by using poly(sodium acrylate) (PANa) hydrogels (Polymers 1–6) under different amount of crosslinker and initiator. The PANa hydrogels were synthesized from the neutralized acrylic acid (AA) monomer via free radical thermal polymerization by using ammonium persulfate (APS) as an initiator and N,N′‐methylene‐bisacrylamide (MBA) as a crosslinker. These polymers exhibited glass transition temperatures (Tg) of 68–88°C and Td values (5% weight loss temperature) in the range of 190–221°C under nitrogen atmosphere. The PANa hydrogels had swollen ratios ranging from 387 to 4,063%, related to the crosslinking density. The final equilibrium adsorption capacity of the polymers was in the range of 20–39 ppm with an initial ammonium nitrogen concentration of 100 ppm. Among them, Polymer 3 without MBA crosslinker displayed the highest swollen characteristic along with the most efficient adsorption capacity. In comparison, the as‐prepared high crosslinking density hydrogels showed relative lower adsorption capability but higher reusability. The polymer composition in this work determines the ability to absorb and desorb ammonium nitrogen compound.

Use of polyacrylic acid hydrogel in the desalination of seawater of Haql coast of Saudi Arabia

Decreasing freshwater resources of the world has led to the use of seawater for human consumption. But availability of high concentration of salts in seawater makes it unsuitable for direct use, therefore, the seawater is desalinized by various techniques. The present investigation was carried out to test the efficacy of prepared polyacrylic acid hydrogel (PAA) in the desalination of seawater of Haql coast of Saudi Arabia. Hydrogels were prepared from PAA with different concentrations of N, N´- methylene bisacrylamide cross-linker, ammonium persulfate and N, N, N`,N`-tetramethylethylenediamine. Free radical polymerization technique was used to proceed the reaction. The chemical structure was evaluated by infrared spectroscopy. The glass transition temperature was recorded by differential scanning calorimetery. Seawater of Haql coast was used to evaluate the swelling properties of hydrogels. The swelling and desalination of water were measured as a factor of time. The results of the study showed that prepared hydrogels were found helpful in the desalination of water samples. Highest desalination was observed in the gels with the largest pore size.

Simple One Pot Preparation of Chemical Hydrogels from Cellulose Dissolved in Cold LiOH/Urea.

In this work, non-derivatized cellulose pulp was dissolved in a cold alkali solution (LiOH/urea) and chemically cross-linked with methylenebisacrylamide (MBA) to form a robust hydrogel with superior water absorption properties. Different cellulose concentrations (i.e., 2, 3 and 4 wt%) and MBA/glucose molar ratios (i.e., 0.26, 0.53 and 1.05) were tested. The cellulose hydrogel cured at 60 °C for 30 min, with a MBA/glucose molar ratio of 1.05, exhibited the highest water swelling capacity absorbing ca. 220 g H2O/g dry hydrogel. Moreover, the data suggest that the cross-linking occurs via a basic Michael addition mechanism. This innovative procedure based on the direct dissolution of unmodified cellulose in LiOH/urea followed by MBA cross-linking provides a simple and fast approach to prepare chemically cross-linked non-derivatized high-molecular-weight cellulose hydrogels with superior water uptake capacity.

Fabrication and characterization of microwave assisted carboxymethyl cellulose-gelatin silver nanoparticles imbibed hydrogel: Its evaluation as dye degradation

The hybrid hydrogel of carboxymethyl cellulose (CMC) and gelatin was synthesized by grafting of poly(acrylic acid) chains in the presence of ammonium persulphate (APS) as initiator and N, N′–methylenebisacrylamide (MBA) as cross-linker in aqueous medium using microwave irradiation method. The hydrogel showed swelling ratio (SR) of 80 g/g at pH 10.0. FTIR of hydrogel confirmed the interaction of CMC and gelatin through cross-linker MBA to form a three-dimensional network. SEM studies further confirmed the three dimensional cross-linked porous structure of synthesized hydrogel. The addition of gelatin to CMC modified the network architecture and contributed to improved mechanical and thermal properties. The characteristic surface plasmon resonance (SPR) of nanosilver was observed at 414 nm. TEM images showed the formation of spherical nanoparticles with mean particle size of 12 nm and zeta potential value is +34.12 mV, indicated the good stability of silver nanoparticles. XRD and SAED pattern agreed with fcc crystalline structure of silver nanoparticles within porous network. The silver nanoparticles loaded hybrid hydrogel exhibited a promising catalytic activity for degradation of congo-red and rhodamine B dyes.

Synthesis of Poly(Acrylamide-Graft-Chitosan) Hydrogel: Optimization of The Grafting Parameters and Swelling Studies

Hydrogel polymers were prepared via graft polymerization of acrylamide (AAm) onto chitosan (CTS) backbone in the presence of methylene bisacrylamide (MBA) as cross-linker and ammonium persulfate (APS) as an initiator. Optimizing the crosslinking graft reaction of AAm onto CTS was studied by varying the concentration of CTS and MBA cross-linker and discussing the effect of these conditions on the gel fraction and the grafting parameters. The grafting parameters; grafting percentage (%GP), grafting efficiency (%GE), Add-on (%A) and homopolymer (%H) were studied as a function of the chitosan and the cross-linker concentrations. Also the swelling properties of the prepared hydrogel were examined. In this research, the simple second order kinetic model proposed by Schott has been carried out to describe the swelling mechanism. The effect of the grafting reaction on the thermal properties of the chitosan was also investigated by the thermal gravimetric analysis (TGA). The structure of the prepared hydrogel polymer was confirmed by FT-IR spectra. The porous structure of the hydrogel was observed by the Scanning Electron Microscope (SEM) and also the elemental composition of the prepared hydrogel was identified by using the energy dispersive X-ray (EDX).

Removal of organic dyes and metal ions by cross-linked graft copolymers of cellulose obtained from the agricultural residue

Cellulose extracted from agricultural residue, rice husk was functionalized through free radical grafting with a binary vinyl monomer mixture of 2-acrylamido-2-methylpropane sulfonic acid and acrylic acid in the presence of N,N'-methylene bisacrylamide cross-linker. To ascertain the grafting, the synthesized copolymer, Cell-g-AASO3H-co-AAc was characterized by FESEM, FTIR, XRD and thermal analytical techniques. The swelling behavior of the grafted copolymer, analyzed as a function of pH followed the order 7.0 > 9.4 > 2.2. The as-synthesized graft copolymer was used as an adsorbent for the removal of model malachite green, crystal violet, congo red dyes and Ni(II) and Cu(II) metal ions from aqueous solutions. The adsorption characteristics of the grafted copolymer were studied as a function of contact time, temperature, pH, and concentration. Cationic dyes were adsorbed maximum at pH 7.0 in 90 min contact time, whereas anionic dye was removed under acidic pH of 2.2 in 8 h. Maximum adsorption of Ni(II) and Cu(II) ions was observed at pH 6.0 and temperature of 30 °C after a contact time of 120 min. Among the various kinetic and adsorption isotherm models, the experimental adsorption data were best fitted in pseudo-second-order kinetic model and Langmuir isotherm model for organic dyes and metal ions. From Langmuir adsorption isotherm, maximum sorption capacities of 112.74 and 109.77 mg/g was reported for Ni(II) and Cu(II) ions, respectively. The current study thus proves that the Cell-g-AASO3H-co-AAc copolymer can efficiently be used as an adsorbent for uptake of harmful cationic as well as anionic dyes and toxic metal ions from industrial wastewater.

Efficient adsorptive extraction materials by surface protein‐imprinted polymer over silica gel for selective recognition/separation of human serum albumin from urine

ABSTRACTIn this study, we report the development of adsorptive extraction materials by surface protein‐imprinted polymers (MIPs) over silica gel for selective recognition/separation of human serum albumin (HSA) from urine. The HSA‐imprinted polymers prepared on silica particle had at interface between the silica gel and different MIPs greatly produced enrichment for the binding of protein from the urine. The solid‐phase extraction of the optimized polymer layer was prepared by copolymerization of methacrylic acid (MAA), acrylamide (AAm), and dimethylaminoethylmethacrylate (DMAEMA) and a crosslinker methylenebisacrylamide (MBA) at the mole ratio of 1:158:88 (T:M:C) and showed moderate affinity (<104 order M−1) toward target protein HSA and selectivity. Four analogues, egg white albumin (EWA), bovine serum albumin (BSA), lysozyme (Lyz), and creatinine (Cre) were selected to study the binding efficiency of MIPs in single and binary protein solutions. We studied the influence on recognition ability for HSA and found that prepolymer mixture and matrix flexibility of the optimized thin polymer layer (35 ± 10 nm) on the submicrosilica particles. The high‐binding affinity (QMIP, 86.7 mg g−1) and fast kinetics (180 min) were observed for this synthesized HSA‐MIP when compared with other reported HSA‐MIPs in surface imprinting (5.9 and 11.3 mg g−1) and epitope surface imprinting (46.6 mg g−1) methods. We demonstrated the application in real and synthetic urine samples that the approach allowed the efficient adsorption of HSA in real urine (129.48 mg g−1) is almost double to the binding of HSA in synthetic urine (67.84 mg g−1). Apart from this, only minor interference of Cre (2.74 mg g−1) was observed, eventhough Cre is the final metabolite in urine. These adsorptive submicrosilica materials have potential in the pharmaceutical industry and clinical analysis applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46894.