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Coumarin-containing amphiphilic block copolymers with different compositions, as a new class of pH- and photo-responsive flocculants, were synthesized through reversible addition-fragmentation chain transfer polymerization of dimethyl aminoethyl methacrylate (DMAEMA), methyl methacrylate, and 7-acryloyloxy 4-methylcoumarin. Proton nuclear magnetic resonance spectroscopy was used to study the structure and composition of the copolymers. Zeta potential results show that the copolymers are applicable as amphoteric flocculants. The optimal flocculant concentration was calculated using the Jar analysis for kaolin flocculation, and the results show that the flocculation dependence on the flocculent concentration decreases with increasing its molecular weight. The dominance of charge neutralization in the flocculants with lower molecular weights and the dominance of adsorption bridging and hydrophobic association in the flocculants with higher molecular weights were indicated. These results are in agreement with the rheological data. To investigate the governing mechanism more precisely, the flocculation rate was calculated using turbidity measurements at different pH values over time. The highest final flocculation rate (99.25 %) corresponds to pH 4.5, which caused by the protonation of the amine groups of the DMAEMA repeating units. The dependence of settling rate on pH indicates the pH-dependent performance of the flocculants. Finally, fluorescence microscopy image of the flocculants shows its proper functioning of in the vicinity of kaolin, which has a promising industrial application. [Display omitted] • Synthesis of a pH- and photo-responsive block copolymer by RAFT polymerization. • Application of the coumarin-containing block copolymer as flocculant. • Calculation of the optimal flocculant concentration using the Jar analysis for kaolin. • The dominance of charge neutralization in flocculants with lower molecular weights. • The dominance of adsorption bridging and hydrophobic association in flocculants with higher molecular weights. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of a magnetic polystyrene nanocomposite for efficient oil spill cleanup. • Coumarin-containing block copolymer was synthesized by RAFT polymerization. • The block copolymer was served as an emulsifier in polystyrene emulsion polymerization. • The nanocomposites have the ability to absorb oil up to 2.31 times of their own weight. • The Hofmeister effect was evaluated for polystyrene particles. Both human health and marine life are seriously threatened by crude oil spills into bodies of water. For effective crude oil spill cleaning, we created a magnetic polystyrene (m-PS) nanocomposite. The use of magnetic nanoparticles makes crude oil absorption more environmentally friendly by making it easier to collect and recycle using an external magnetic field. To make Fe 3 O 4 nanoparticles compatible with the hydrophobic styrene monomer used in emulsion polymerization, they were treated using a hydrophobic surface modification reaction. This alteration facilitated the grafting of polystyrene (PS) chains onto the nanoparticles, which then underwent emulsion polymerization. As an emulsifier, a light-responsive amphiphilic block copolymer containing coumarin was created via reversible addition-fragmentation chain transfer polymerization. This allowed for regulated emulsification and demulsification in response to UV stimulation. The synthesized m-PS nanocomposite demonstrated a crude oil absorption capacity of up to 2.31 times of its own weight, indicating its high efficiency for crude oil spill cleanup. The synthetic emulsifier exhibited a significantly lower critical micelle concentration compared to the commercial P105 emulsifier (0.0976 against 0.354 mg/mL, respectively), indicating higher efficiency and reduced environmental impact. For a more thorough comprehension of the reported results, we also assessed the Hofmeister effect in PS produced using commercial and synthetic emulsifiers. [ABSTRACT FROM AUTHOR]

To address the substantial corrosion problem associated with magnesium alloy (AZ31), submicron particles of PLGA (poly(lactic- co -glycolic acid)) containing 2-mercaptobenzimidazole (IMZ) and curcumin (CUR) were developed using a novel pH-responsive acrylate-based polymeric surfactant (APS) through nanoprecipitation. To achieve this, an acrylate-based block copolymer through reversible addition−fragmentation chain transfer (RAFT) radical polymerization was synthesized as a first step. Findings indicated that APS exhibited a remarkable ability to produce spherical nanosized particles, particularly at low concentrations. The primary objective of this research was to develop drug carriers for AZ31 implants. So, CUR/IMZ have been loaded in the obtained particles were loaded and the release profiles of loaded particles were evaluated accordingly. The results revealed that the system significantly reduced the corrosion rate of AZ31 in a test solution, primarily due to the presence of IMZ, with the optimum sample exhibiting a polarization resistance of 7026 Ω.cm−2. Finally, cell viability was carried out and the results showed that approximately 81 % of cells remained viable after 24 h of exposure. It is worth noting that the issue of bacterial infections in AZ31 implants was mitigated (with a reduction in bacterial growth) by tailoring the PLGA particles to contain CUR as an antibacterial agent. [Display omitted] • The pH-sensitive amphiphilic block copolymer was synthesized by RAFT polymerization method. • The designed particle-loaded coating protects AZ31 by the barrier mechanism. • The anti-corrosion, antibacterial and cytotoxic properties of the above coating were evaluated. [ABSTRACT FROM AUTHOR]

Cellular transplantation, due to the low regenerative capacity of the Central Nervous System (CNS), is one of the promising strategies in the treatment of neurodegenerative diseases. The design and application of scaffolds mimicking the CNS extracellular matrix features (biochemical, bioelectrical, and biomechanical), which affect the cellular fate, are important to achieve proper efficiency in cell survival, proliferation, and differentiation as well as integration with the surrounding tissue. Different studies on natural materials demonstrated that hydrogels made from natural materials mimic the extracellular matrix and supply microenvironment for cell adhesion and proliferation. The design and development of cellular microstructures suitable for neural tissue engineering purposes require a comprehensive knowledge of neuroscience, cell biology, nanotechnology, polymers, mechanobiology, and biochemistry. In this review, an attempt was made to investigate this multidisciplinary field and its multifactorial effects on the CNS microenvironment. Many strategies have been used to simulate extrinsic cues, which can improve cellular behavior toward neural lineage. In this study, parallel and align, soft and injectable, conductive, and bioprinting scaffolds were reviewed which have indicated some successes in the field. Among different systems, three-Dimensional (3D) bioprinting is a powerful, highly modifiable, and highly precise strategy, which has a high architectural similarity to tissue structure and is able to construct controllable tissue models. 3D bioprinting scaffolds induce cell attachment, proliferation, and differentiation and promote the diffusion of nutrients. This method provides exceptional versatility in cell positioning that is very suitable for the complex Extracellular Matrix (ECM) of the nervous system. [ABSTRACT FROM AUTHOR]

The present study reports a case of solitary neurofibroma attached to the Inferior Rectus (IR) muscle tendon in a 24-year-old healthy woman and reviews the relevant literature regarding the clinical presentation, diagnosis, and management of this uncommon tumor. The patient underwent successful surgical resection of the tumor, leading to the resolution of associated symptoms (left lower eyelid protrusion and redness). Pathological examination confirmed the diagnosis of neurofibroma based on characteristic histopathological and immunohistochemical markers. This case report underscores the rarity of solitary neurofibromas and primary neoplasms of orbit and ocular adnexa. We also discuss the background of solitary neurofibromas originating from orbit and ocular adnexa. The successful management of this case through surgical resection highlights the importance of accurate diagnosis and tailored treatment strategies. To the best of our knowledge, this is the first reported solitary neurofibroma confined solely to the IR tendon. [ABSTRACT FROM AUTHOR]

Controlled drug release (CDR) is a significant field of research in medical sciences due to its numerous clinical advantages over traditional methods. Encapsulation of a drug in a polymeric matrix is common technique to achieve CDR. In this study, drug‐polymer particles are prepared using poly(lactic‐co‐glycolic acid) (PLGA) as the polymer and curcumin (CUR) as model drug. Two different methods, electrospray and nanoprecipitation, are used to prepare the particles, and optimal samples in each process are selected based on size and polydispersity index (PDI). Samples are characterized using various tests, and entrapment efficiency (EE%) and drug loading (DL%) are calculated using UV spectroscopy. The results showed that nanoprecipitated and electrosprayed PLGA particles successfully encapsulated CUR, with higher encapsulation efficiency (93.2%) and loading capacity (7.2%) for electrosprayed particles. The in vitro drug release showed that electrospray particles have a slower release rate due to higher encapsulation efficiency. The electrospray method turned out to be more viable for synthesizing these polymer‐drug particles due to smaller particle size, lower PDI, higher entrapment efficiency, and drug loading percentage. Finally, the antibacterial behavior of the particles proved that prepared particles provide excellent antibacterial efficacy (99.9%) and can be used as drug delivery systems. [ABSTRACT FROM AUTHOR]

The hybridization of dissimilar materials is assumed as a promising route to improve their desired properties for various purposes. In this work, the ferrocene-functionalized graphene nanoribbon/dicationic ionic liquid/poly (ortho-aminophenol) nanocomposite (abbreviated here to GNR-Fc/DCIL/PoAP-NC) was synthesized as a novel active material for high-performance battery-type supercapacitor (SC) applications. In this context, the electrochemical measurement outcomes revealed the significantly enhanced capacitance of the final NC, as compared to those of each component. Additionally, the specific capacitance achieved for the given NC was 395 mAh/g (current density: 1 A/g), wherein energy density (E sg) and power density (P sg) were equal to 29.625 Wh/kg and 852 W/kg, respectively. These results could be attributed to the synergistic effects of the NC components, reducing the charge transfer resistance (R ct) and expanding the charge transfer properties of the GNR. The impact of the molecular weight of the polymeric ionic liquid (PIL) on the electric charge transfer was correspondingly evaluated. Even with the higher number of the charge transfer sites; the charge transfer became more complex following the increase in the chain length, which could be caused by the time-consuming diffusion of the charged species. As a final point, the performance of the novel active material, the GNR-Fc/DCIL/PoAP-NC, in the structure of the two-electrode cell was investigated. [Display omitted] • Graphene Nano Ribbon was functionalized by ferrocene using a novel silane bridge. • Imidazolium-based ionic liquids were synthesized in various molecular weights. • P-type conductive polymer(PoAP) was synthesized by a chemical manner. • The ternary GFc/IL/PoAP nanocomposites were prepared for battery-type supercapacitors. • Electrochemical behavior in two- and three-electrode structures were investigated. [ABSTRACT FROM AUTHOR]

The efficient production of a high concentration of bacteriophage in large volumes has been a limiting factor in the exploration of the true potential of these organisms for biotechnology, agriculture and medicine. Traditional methods focus on generating small volumes of highly concentrated samples as the end product of extensive mechanical and osmotic processing. To function at an industrial scale mandates extensive investment in infrastructure and input materials not feasible for many smaller facilities. To address this, we developed a novel, scalable, generic method for producing significantly higher titer psychrophilic phage ( P < 2.0 × 10 −6 ), 2- to 4-fold faster than traditional methods. We generate renewable high yields from single source cultures by propagating phage under refrigeration conditions in which Listeria , Yersinia and their phages grow in equilibrium. Diverse Yersinia and Listeria phages tested yielded averages of 3.49 × 10 8 to 3.36 × 10 12 PFU/ml/day compared to averages of 1.28 × 10 5 to 1.30 × 10 10 PFU/ml/day by traditional methods. Host growth and death kinetics made this method ineffective for extended propagation of mesophilic phages. [ABSTRACT FROM AUTHOR]

Thermoplastic polyurethane elastomers (TPUs) reinforced with multi wall carbon nanotubes (MWCNTs) and Closite30B, were prepared via melt mixing approach and investigated by spectroscopy, and rheological analyses. Following basic analyses, time sweep tests were used to determine the influence of temperature, applied preshear and nanofiller content and aspect ratio on the micro‐phase separation kinetics of the nanocomposites. Based on the experimental results, artificial neural network was developed to explain the relationship between those parameters and micro‐phase separation time. The neural network is able to predict micro‐phase separation time of TPU nanocomposites possessing different nanofillers at various shear rates and temperatures. Comparison between experimental and calculated data by the model shows that the neural network can well‐communicate between input and target variables. POLYM. COMPOS., 40:3904–3913, 2019. © 2019 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]