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[Display omitted] • Hybrid and UV-sensitive nanoparticles were successfully synthesized. • Layer-by-layer assembly of oppositely charged polysaccharides was performed. • UV irradiation reduced the turbidity of core–shell nanoparticles suspension. • "Optically hollow" particles are composed of only glass and plant-based materials. Hollow nanoparticles have been extensively studied in recent years. Obtaining such structures with biobased materials, following greener synthetic routes, is still challenging, especially if accurate particle dimensions are required. This work reports the use of an innovative hybrid silica core (Si@azo) containing UV-sensitive molecule, wrapped in biobased multilayer shell composed of polysaccharides. It is a promising strategy for obtaining optically hollow nanoparticles. Indeed, Si@azo cores have the ability to be partially degraded when irradiated with UV light. Combined with a well-controlled and monodisperse diameter, they provide a good basis for layer-by-layer assembly, leading to a multilayer shell with controlled composition and thickness. Finally, UV irradiation of such a core–shell structure is harmless to the polysaccharide shell, but does impact the hybrid silica core, as revealed by turbidity measurements, among other. Each step, i.e. core synthesis, shell addition, and core–shell irradiation, has been carefully characterized at the macro (Fourier-transform infrared spectroscopy – FTIR, Dynamic Light Scattering – DLS, Zeta-potential measurement, Surface Plasmon Resonance – SPR, turbidity) and microscale (Transmission and Scanning Electron Microscopies). Emphasis is put on how turbidity measurements can be related to the core refractive index (n core), giving information on the state of core degradation and whether the core–shell particle is optically hollow. [ABSTRACT FROM AUTHOR]

Poly(3, 4-ethylenedioxyethiophene)-polystyrene sulfonic acid (PEDOT:PSS)/polyallyl dimethyl ammonium chloride modified reduced graphene oxide (PDDA-rGO) was layer by layer self-assembled on the cotton fiber. The surface morphology and electric property was investigated. The results confirmed the dense membrane of PEDOT: PSS and the lamellar structure of PDDA-rGO on the fibers. It has excellent electrical conductivity and mechanical properties. The fiber based electrochemical transistor (FECTs) prepared by the composite conductive fiber has a maximum output current of 8.7 mA, a transconductance peak of 10 mS, an on time of 1.37 s, an off time of 1.6 s and excellent switching stability. Most importantly, the devices by layer by layer self-assembly technology opens a path for the true integration of organic electronics with traditional textile technologies and materials, laying the foundation for their later widespread application. [ABSTRACT FROM AUTHOR]

In this work, Preyssler‐type POM (NH4)14[NaP5W30O110].44H2O (NH4P5W30), has been synthesised and its electrochemical behaviour in solution was examined at the surface of glassy carbon (GC) and gold electrodes. Furthermore, multilayer assemblies of NH4P5W30 POM were constructed onto the surfaces of GCE, gold electrode, and gold quartz electrode via the electrostatic Layer‐by‐Layer (LBL) technique employing polyethyleneimine as the cationic layer and POM as an anionic layer. Cyclic voltammetry, electrochemical impedance spectroscopy (EIS), and electrochemical quartz crystal microbalance measurements (EQCM) were used to monitor the LBL assembly as the NH4P5W30 POM layer was being built. These techniques revealed significant differences in film growth. The multilayer film exhibited well‐defined redox couples associated with POM's tungsten‐oxo framework and showed surface‐confined behaviour up to 100 mVs−1 on both the GC and gold electrodes. The pH dependency and stability of the film were investigated. EIS demonstrated that when the POM layer was the outer layer, the layers were less conductive, and resistance increased as the number of layers increased. In addition, the charge transfer resistance values (Rct) for the layers were calculated. The solvation of ions into the film associated with POM redox activity was studied employing an in‐situ EQCM. [ABSTRACT FROM AUTHOR]

The layer‐by‐layer (LbL) organic photovoltaics (OPVs) are constructed with wide‐bandgap donor PM1 and narrow‐bandgap acceptor L8‐BO. The exciton utilization near cathode is still challenging considering restricted diffusion distance of excitons and inability for transferring energy from L8‐BO to PM1. Herein, donor incorporation into acceptor layer (DIA) strategy is employed to improve exciton utilization near cathode. The efficiency of LbL OPVs can be improved from 18.02% to 18.81% by incorporating 10 wt% PM1 into L8‐BO layer, which is closely associated with efficient exciton separation into L8‐BO layer originated from more adequate donor/acceptor interface for faster charge transfer, as evidenced by magneto‐photocurrent and transient absorption results. The in situ test and morphological characterization clarify that molecular packing property can be improved benefited from prolonged aggregation and nucleation time of acceptor layer assisted by DIA strategy, contributing to more efficient charge transport and inhibited charge recombination in active layers. The thickness insensitive property of LbL OPVs can be also improved induced by DIA strategy, indicated by PCE retention value (82.2% vs. 74.0%) for PM1/L8‐BO:PM1 and PM1/L8‐BO OPVs when acceptor layer thickness increased to ≈180 nm. This work demonstrates the effectiveness of DIA strategy in improving efficiency and thickness tolerance of LbL OPVs. [ABSTRACT FROM AUTHOR]

This article presents studies on the evaluation of the impact of surface modification of cotton, viscose, and polyester fabrics using three techniques (flocking, layer by layer, and screen printing) with materials with electrically conductive properties on their structural, biophysical, and conductive properties. Each tested fabric is characterized by specific biophysical properties. which can be disturbed by various modification methods, therefore, the following tests were carried out in the article: optical microscopy, micro-computed tomography, guarded perspiration heating plate, air permeability, sorption and electrical conductivity tester. The use of screen printing increased the thermal resistance of the cotton woven fabric by 119%, the polyester woven fabric by 156%, and the viscose fabric by 261%. The smallest changes in thermal resistance compared to unmodified textiles were observed in layer by layer modified fabrics and are as follows: −15% (cotton woven fabric), +77% (PES woven fabric), and +80% (viscose woven fabric). [ABSTRACT FROM AUTHOR]

The driving force of Oman's economy is oil and gas industries with a fairly diversified treasure among Gulf cooperation council countries. The corrosion problems in oil pipelines would be successfully resolved by means of novel control techniques. The current study aimed to synthesize aluminium oxide (Al2O3) nanoparticles from waste aluminium foil and to assess its potential application in corrosion inhibition of mild steel pipe. Al2O3 nanoparticles have been synthesized by facile co-precipitation technique at room temperature. The synthesized Al2O3 nanoparticles have been used to fabricate nanocomposite thin films using a biopolymer, chitosan by dip coating technique and to carry out corrosion inhibition studies of mild steel pipe. The characterisation techniques employed are scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, energy dispersive X-ray analysis, atomic force microscopy. Atmosphere test and Wet/Dry tests are carried out to investigate the corrosion behaviour of coated specimen. From the experimental studies, it is observed that the chitosan -- Al2O3 nano thin film could inhibit the corrosion and also to enhance the lifespan of the mild steel pipe. This novel research project is aligned with the United Nations Sustainable Development Goals (UNSDG- 9: Industry, Innovation and Infrastructure) and Oman vision 2040. The study demonstrates that the chitosan -- Al2O3 composite thin films fabricated using dip coating technique with minimum film thickness can be a feasible solution in controlling the corrosion in oil pipelines with good film stability, high durability, with a cost effective and environmentally friendly approach. [ABSTRACT FROM AUTHOR]

Abstract In this work, Preyssler‐type POM (NH4)14[NaP5W30O110].44H2O (NH4P5W30), has been synthesised and its electrochemical behaviour in solution was examined at the surface of glassy carbon (GC) and gold electrodes. Furthermore, multilayer assemblies of NH4P5W30 POM were constructed onto the surfaces of GCE, gold electrode, and gold quartz electrode via the electrostatic Layer‐by‐Layer (LBL) technique employing polyethyleneimine as the cationic layer and POM as an anionic layer. Cyclic voltammetry, electrochemical impedance spectroscopy (EIS), and electrochemical quartz crystal microbalance measurements (EQCM) were used to monitor the LBL assembly as the NH4P5W30 POM layer was being built. These techniques revealed significant differences in film growth. The multilayer film exhibited well‐defined redox couples associated with POM's tungsten‐oxo framework and showed surface‐confined behaviour up to 100 mVs−1 on both the GC and gold electrodes. The pH dependency and stability of the film were investigated. EIS demonstrated that when the POM layer was the outer layer, the layers were less conductive, and resistance increased as the number of layers increased. In addition, the charge transfer resistance values (Rct) for the layers were calculated. The solvation of ions into the film associated with POM redox activity was studied employing an in‐situ EQCM.

Phytic acid (PA)-coated zinc oxide (ZnO) nanoparticles were developed to produce high-efficiency flame-retarding (FR) additives for coating formulations. These hybrid (organic/inorganic) additives were fabricated using a layer-by-layer (LBL) approach to harness the FR properties of PA and ZnO on a single-platform nanoscale scaffold. These nanoparticles can be uniformly dispersed in a polyurethane (PU) coating for applications on metal substrates. The incorporation of the PA/ZnO layer-by-layer nanoparticles at 20 wt% of the polymeric resin did not adversely affect the physico-mechanical properties of the coatings. Flame-retardant properties of PU samples containing nanomaterials, showed a 50% reduction in flame spread rate than that observed from the samples prepared with only ZnO nanoparticles. Cone calorimeter studies performed on the metal panels coated with 20 wt% PA/ZnO nanoparticles-infused PU resins showed a 25% reduction in peak heat release rate and a 50% reduction in total heat release (THR) compared to control coatings prepared without nanoparticles. Scanning electron microscopy images revealed the presence of bubble-like morphologies in the burnt samples containing the nanoparticles, indicating char formation and obstruction of escaping gases produced during the burning of the coating materials. This study clearly reveals that the coatings prepared with PA/ZnO hybrid nanoparticles can protect metal substrates against fire-related damage. [ABSTRACT FROM AUTHOR]

Two addition orders, i.e., the layer-by-layer (L) and mixed biopolymer (M) orders, were used to generate sodium caseinate - sugar beet pectin electrostatically stabilized o/w emulsions with 0.5% oil and varying sodium caseinate: sugar beet pectin ratios (3:1–1:3) at pH 4.5. Emulsion stability against environmental stresses (i.e., pH, salt addition, thermal treatment, storage and in vitro simulated gastrointestinal digestion) and its astaxanthin encapsulation against degradation during storage and in vitro digestion were evaluated. Results indicated that a total biopolymer concentration of 0.5% was optimal, with the preferred sodium caseinate-sugar beet pectin ratios for L and M emulsions being 1:1 and 1:3, respectively. L emulsions generally exhibited smaller droplet diameters than M emulsions across all ratios, except at 1:3. Lowering the pH to 1.5 substantially reduced the net negative charge of all emulsions, with only L emulsions precipitating at pH 3. M emulsions showed greater tolerance to salt addition, remaining stable up to 500 mM sodium and calcium concentrations, whereas L emulsions destabilized at levels exceeding 50 mM and 30 mM, respectively. All emulsions were stable when heated at 37 °C or 90 °C for 30 min. Astaxanthin degradation rates increased with prolonged storage, reaching 61.66% and 54.08% by day 7 for L and M emulsions, respectively. Encapsulation efficiency of astaxanthin in freshly prepared M emulsions (86.85%) was significantly higher compared to L emulsions (72.82%). M emulsions had 30% and 25% higher encapsulation efficiency of astaxanthin than L emulsions after in vitro digestion for 120 min and 240 min respectively. This study offers suggestions for interface design and process optimization to improve the performance of protein-polysaccharide emulsion systems, such as in beverages and dairy products, as well as their delivery effect of bioactives.

Bioactive surface coatings have retained the attention of researchers and physicians due to their versatility and range of applications in orthopedics, particularly in infection prevention. Antibacterial metal nanoparticles (mNPs) are a promising therapeutic, with vast application opportunities on orthopedic implants. The current research aimed to construct a polyelectrolyte multilayer on a highly porous titanium implant using alternating thin film coatings of chitosan and alginate via the layer-by-layer (LbL) self-assembly technique, along with the incorporation of silver nanoparticles (AgNPs) or titanium dioxide nanoparticles (TiO2NPs), for antibacterial and osteoconductive activity. These mNPs were characterized for their physicochemical properties using quartz crystal microgravimetry with a dissipation system, nanoparticle tracking analysis, scanning electron microscopy, and atomic force microscopy. Their cytotoxicity and osteogenic differentiation capabilities were assessed using AlamarBlue and alkaline phosphatase (ALP) activity assays, respectively. The antibiofilm efficacy of the mNPs was tested against Staphylococcus aureus. The LbL polyelectrolyte coating was successfully applied to the porous titanium substrate. A dose-dependent relationship between nanoparticle concentration and ALP as well as antibacterial effects was observed. TiO2NP samples were also less cytotoxic than their AgNP counterparts, although similarly antimicrobial. Together, these data serve as a proof-of-concept for a novel coating approach for orthopedic implants with antimicrobial and osteoconductive properties. [ABSTRACT FROM AUTHOR]

This article presents studies on the evaluation of the impact of surface modification of cotton, viscose, and polyester fabrics using three techniques (flocking, layer by layer, and screen printing) with materials with electrically conductive properties on their structural, biophysical, and conductive properties. Each tested fabric is characterized by specific biophysical properties. which can be disturbed by various modification methods, therefore, the following tests were carried out in the article: optical microscopy, micro-computed tomography, guarded perspiration heating plate, air permeability, sorption and electrical conductivity tester. The use of screen printing increased the thermal resistance of the cotton woven fabric by 119%, the polyester woven fabric by 156%, and the viscose fabric by 261%. The smallest changes in thermal resistance compared to unmodified textiles were observed in layer by layer modified fabrics and are as follows: −15% (cotton woven fabric), +77% (PES woven fabric), and +80% (viscose woven fabric).

Novel wound dressing materials are required to non-cytotoxic with a viable cell ratio of above 92%. Herein, the cytotoxicity of hyaluronic acid/chitosan/bacterial cellulose-based (BC(CS/HA)) membranes are evaluated and compared to that of alginate/chitosan/bacterial cellulose-based (BC(CS/Alg)) membranes was investigated. Multilayer membranes with up to ten CS/HA or CS/Alg layers were prepared using the layer-by-layer (LBL) method. Scanning electron microscopy showed that the diameters of the fibers in the BC(CS/Alg) and BC(CS/HA) membranes were larger than those in a BC membrane. The cytotoxicity was analyzed using BALB-3T3 clone A31 cells (mouse fibroblasts, 1 × 104 cells/well). The BC(CS/HA)5 and BC(CS/HA)10 membranes exhibited high biocompatibility, with the cell viabilities of 94% and 87% at 5 d, respectively, compared to just 82% for the BC(CS/Alg)5 and BC(CS/Alg)10 membranes with same numbers of layers. These results suggested that BC(CS/HA)5 is a promising material for wound dressings. [ABSTRACT FROM AUTHOR]

Due to their extraordinary prospective uses, particularly in the areas of oil–water separation, underwater superoleophobic materials have gained increasing attention. Thus, artificial nacre has become an attractive candidate for oil–water separation due to its superhydrophilicity and underwater superoleophobicity properties. Synthesized artificial nacre has successfully achieved a high mechanical strength that is close to or even surpasses the mechanical strength of natural nacre. This can be attributed to suitable synthesis methods, the selection of inorganic fillers and polymer matrices, and the enhancement of the mechanical properties through cross-linking, covalent group modification, or mineralization. The utilization of nacre-inspired composite membranes for emerging applications, i.e., is oily wastewater treatment, is highlighted in this review. The membranes show that full separation of oil and water can be achieved, which enables their applications in seawater environments. The self-cleaning mechanism's basic functioning and antifouling tips are also concluded in this review. [ABSTRACT FROM AUTHOR]

Being cheap, nondestructive, and easy to use, gas sensors play important roles in the food industry. However, most gas sensors are suitable more for laboratory-quality fast testing rather than for cold-chain continuous and cumulative testing. Also, an ideal electronic nose (E-nose) in a cold chain should be stable to its surroundings and remain highly accurate and portable. In this work, a portable film bulk acoustic resonator (FBAR)-based E-nose was built for real-time measurement of banana shelf time. The sensor chamber to contain the portable circuit of the E-nose is as small as a smartphone, and by introducing an air-tight FBAR as a reference, the E-nose can avoid most of the drift caused by surroundings. With the help of porous layer by layer (LBL) coating of the FBAR, the sensitivity of the E-nose is 5 ppm to ethylene and 0.5 ppm to isoamyl acetate and isoamyl butyrate, while the detection range is large enough to cover a relative humidity of 0.8. In this regard, the E-nose can easily discriminate between yellow bananas with green necks and entirely yellow bananas while allowing the bananas to maintain their biological activities in their normal storage state, thereby showing the possibility of real-time shelf time detection. This portable FBAR-based E-nose has a large testing scale, high sensitivity, good humidity tolerance, and low frequency drift to its surroundings, thereby meeting the needs of cold-chain usage. HIGHLIGHTS: • A compact FBAR-based E-nose was built for gas sensing. A portable field-programmable gate array (FPGA) circuit was used for FBAR frequency testing instead of a traditional PC-sized vector network analyzer (VNA). • The sensitivity is 5 ppm to ethylene and 0.5 ppm to isoamyl acetate and isoamyl butyrate, while the detection range is large enough to cover a relative humidity of 0.8. • With the help of a reference FBAR and the low FBAR temperature drift, the E-nose reduces the drift caused by its surroundings. Also, the LBL coating method was used to increase the FBAR sensitivity. As a result, the E-nose can realize real-time banana shelf-time detection and can easily discriminate between yellow bananas with green necks and entirely yellow bananas. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cell-derived exosomes (MSC-Exos) have attracted much attention as a potential cell-free therapy for ulcerative colitis (UC), mainly due to their anti-inflammatory, tissue repair, and immunomodulatory properties. Although intravenous injection of MSC-Exos is able to improve UC to a certain extent, oral administration of exosomes is the preferred method to treat gastrointestinal diseases such as UC. However, exosomes contain proteins and nucleic acids that are vulnerable to degradation by the gastrointestinal environment, making oral administration difficult to implement. Layer-by-layer (LbL) self-assembly technology provides a promising strategy for the oral delivery of exosomes. Therefore, an efficient LbL-Exos self-assembly system was constructed in this study for the oral delivery of exosomes targeted to the colon to improve UC treatment. Biocompatible and biodegradable N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC) and oxidized konjac glucomannan (OKGM) polysaccharides were used as the outer layers to provide colon targeting and to protect exosomes from degradation. Similar to plain exosomes, LbL-Exos had a similar structure and features, but LbL provided controlled release of exosomes in the inflammatory colon. Compared with intravenous administration, oral administration of LbL-Exos could effectively alleviate UC using half the number of exosomes. Mechanistic studies showed that LbL-Exos were internalized by macrophages and intestinal epithelial cells to exert anti-inflammatory and tissue repair effects and therefore alleviate UC. Furthermore, the LbL-Exos system was able to improve UC via MAPK/NF-κB signaling pathway inhibition. Overall, our data show that LbL-MSC-Exos can alleviate UC after oral administration and therefore may constitute a new strategy for UC treatment in the future. [Display omitted] • An efficient MSC-Exos oral delivery system to improve UC therapy • LbL self-assembly technology provides exosomes protection and colon targeting. • LbL-Exos had good biocompatibility, stability and sustained release behaviors. • LbL-Exos alleviate UC using half dosage of exosomes compared with i.v. • The underlying therapeutic mechanisms of LbL-Exos were explored. [ABSTRACT FROM AUTHOR]

A MnO-Mn 3 O 4 /MnS heterostructure-anchored 3D porous graphene architecture with CNT-reinforced interface was successfully constructed and applied as supercapacitors thick electrodes via straightforward layer-by-layer structural engineering. Based on the electrodes, symmetrical supercapacitor with a broadened potential window of 1.3 V obtained a prominent electrochemical performance. [Display omitted] • Thick electrode is constructed by all-laser layer-by-layer structural engineering. • Heterostructure and graphene are synchronously synthesized during laser irradiation. • MnO-Mn 3 O 4 /MnS heterostructure provides a high electrochemical activity. • CNT interface and porous graphene supply fast electron/ion transport capability. • The assembled supercapacitor exhibits a prominent electrochemical performance. The emerging thick electrode concept is dedicated to maximize active material areal loading at the device-scale through straightforward structural designs to meet the high energy density demand. Nevertheless, overcoming the sluggish charge kinetics and complex manufacturing route in thick composite electrodes is still challenging. Herein, a novel all-laser structural engineering protocol is developed to construct MnO-Mn 3 O 4 /MnS heterostructure-anchored 3D porous graphene architecture with reinforced carbon nanotube (CNT) interface (MHGC) by layer-by-layer laser induction of polyethersulfone film containing manganese acetate precursors without introducing any templates or catalysts. Creatively, along with the synchronous generation of porous graphene and multivalent manganese compounds heterostructures, a uniform distribution process of nanoparticles is integrated into a one-step in-situ laser irradiation, which is unique and straightforward for preparing thick composite electrodes. Besides, the interlayer bridging of CNT network between MnO-Mn 3 O 4 /MnS/graphene layers accelerates electron transport, accompanied by the ameliorative deep diffusion of ions by open graphene macropores derived from laser-assisted vaporization. Thanks to the configuration of efficient electronic bridge and ion channel, combined with multi-heterointerface and fast surface reaction kinetics endowed by heterostructure nanoparticles, MHGC electrode with a thickness of 442 μm delivers a high specific capacitance of 954.5 mF cm−2 (at 0.5 mA cm−2). The assembled symmetrical supercapacitor with LiCl aqueous electrolyte exhibits a broadened potential window of 1.3 V, obtaining a prominent energy density (39.99 μWh cm−2) and power density (1625 μW cm−2). This advanced laser engineering and enabled thick electrodes open a brand-new avenue in burgeoning energy chemistries, not limited to supercapacitors and rechargeable batteries. [ABSTRACT FROM AUTHOR]

Bioactive surface coatings have retained the attention of researchers and physicians due to their versatility and range of applications in orthopedics, particularly in infection prevention. Antibacterial metal nanoparticles (mNPs) are a promising therapeutic, with vast application opportunities on orthopedic implants. The current research aimed to construct a polyelectrolyte multilayer on a highly porous titanium implant using alternating thin film coatings of chitosan and alginate via the layer-by-layer (LbL) self-assembly technique, along with the incorporation of silver nanoparticles (AgNPs) or titanium dioxide nanoparticles (TiO2NPs), for antibacterial and osteoconductive activity. These mNPs were characterized for their physicochemical properties using quartz crystal microgravimetry with a dissipation system, nanoparticle tracking analysis, scanning electron microscopy, and atomic force microscopy. Their cytotoxicity and osteogenic differentiation capabilities were assessed using AlamarBlue and alkaline phosphatase (ALP) activity assays, respectively. The antibiofilm efficacy of the mNPs was tested against Staphylococcus aureus. The LbL polyelectrolyte coating was successfully applied to the porous titanium substrate. A dose-dependent relationship between nanoparticle concentration and ALP as well as antibacterial effects was observed. TiO2NP samples were also less cytotoxic than their AgNP counterparts, although similarly antimicrobial. Together, these data serve as a proof-of-concept for a novel coating approach for orthopedic implants with antimicrobial and osteoconductive properties.

[Display omitted] Herein, a facile green synthetic protocol for nanoporous NiFe-LDH/MoO x /BiVO 4 had been established via an electrochemical deposition method for enhanced photoelectrochemical cell (PEC) performance. The rational design of nanoporous NiFe-LDH/MoO x /BiVO 4 played a vital role in improving the photocurrent density and achieving 2.7 mA /cm2 at 1.23 V RHE (3.9 - fold higher than BiVO 4) with a negative onset potential of 267 mV offset. Moreover, the holes were efficiently consumed for water splitting through the cyclic reaction of NiFe-LDH layer. Thus, the nanoporous NiFe-LDH/MoO x /BiVO 4 photoanode dramatically improved bulk charge transfer efficiency and surface charge injection efficiency reaching nearly 50% and 95% at 1.23 V RHE , respectively. In addition, the accumulated charge test proved that Mo oxide had the function of transferring holes. And the highest photovoltage and lowest charge recombination kinetics of composite photoanode also presented that the oxide species of Mo and NiFe-LDH had the properties of a passivation layer which were characterized by OCP (Open Circuit Potential) and IMPS (Intensity Modulated Photocurrent Spectroscopy) test. The excellent photocurrent density and facile layer-by-layer synthesis of NiFe-LDH/MoO x /BiVO 4 nanocomposite made it a promising photocatalytic material for practical applications. This newly designed strategy was anticipated to be applied in future promising photoanodes for PEC water splitting. [ABSTRACT FROM AUTHOR]

Among mucosal administration routes for vaccines, the sublingual route has been proven capable of inducing a potent systemic and mucosal immune response. However, the absence of a simple and compliant delivery system and the lack of robust mucosal adjuvants impede the development of sublingual vaccines. Here, we describe a mucoadhesive patch made of a layer-by-layer assembly of polysaccharides, chitosan, and hyaluronic acid. The mucoadhesive patch was covered by adjuvanted nanoparticles carrying viral proteins. We showed that the nanoparticles effectively cross the outer layers of the sublingual mucosa to reach the epithelium. Furthermore, the encapsulated adjuvants, 3M-052 and mifamurtide, targeting toll-like receptor (TLR) 7/8 and nucleotide-binding oligomerization domain-2 (NOD2), respectively, remain fully active after encapsulation into nanoparticles and exhibit a cytokine/chemokine signature similar to the mucosal gold-standard adjuvant, the cholera toxin. However, the particulate adjuvants induced more moderate levels of proinflammatory interleukin (IL)-6 and keratinocyte chemoattractant (KC), suggesting a controlled activation of the innate immune response. [ABSTRACT FROM AUTHOR]

As a dangerous cardiovascular disease, acute myocardial infarction (AMI) has taken the lives of countless patients. Symptom onset of AMI is accompanied by a high amount of AMI biomarkers, including creatine kinase isoenzyme (CK-MB), troponin I (CTn I), and myoglobin (Mb). On the other hand, aspirin is an effective curing drug for AMI. Herein, we applied the layer-by-layer (LBL) synthesis strategy to form stratified magnetic core/multishell lanthanide metal–organic framework (Ln-MOF) Fe2O3@SiO2@Eu-MOF@Tb-MOF (MagMOF) nanoballs. Further, target mRNA sequence and antibodies (NH2-mRNA, anti-CTn, and anti-Mb) for AMI biomarkers are combined with MagMOF, respectively. They can be utilized as a hybrid sensing platform for the detection of CK-MB, Mb, and CTn I with high sensitivity (the limit of detection (LOD) for CK-MB is 174.98 U L–1, for CTn I is 0.16 mg L–1, and for Mb is 0.94 mg L–1). The detection ranges of MagMOF toward CK-MB, Mb, and CTn I in human serum have covered their maximum normal range in the human body, respectively. Further, MagMOF was applied in the ratiometric detection of aspirin with high sensitivity and low limit detection (LOD = 0.43 μM). As a result, MagMOF is the first example of realizing stable, susceptible, fast, and convenient detection of these AMI biomarkers and curing drug aspirin. [ABSTRACT FROM AUTHOR]

Alginate hydrogels can be used to develop a three-dimensional environment in which various cell types can be grown. Cross-linking the alginate chains using reversible ionic bonds opens up great possibilities for the encapsulation and subsequent release of cells or drugs. However, alginate also has a drawback in that its structure is not very stable in a culture medium with cellular activity. This work explored the stability of alginate microspheres functionalised by grafting specific biomolecules onto their surface to form microgels in which biomimetic microspheres surrounded the cells in the culture, reproducing the natural microenvironment. A study was made of the stability of the microgel in different typical culture media and the formation of polyelectrolyte multilayers containing polylysine and heparin. Multiple myeloma cell proliferation in the culture was tested in a bioreactor under gentle agitation. [ABSTRACT FROM AUTHOR]

This novel method, called layer by layer, is composed of alternate layers of graphene oxide and bismuth telluride nanoparticles, and to enhance the adsorption capacity the surface of nanoparticles was modified by 4-aminoantipyrine. A high-performance liquid chromatography with fluorescence detector technique was validated and used for analysis of nonylphenol extracted from environment water samples. Fourier-transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray, thermogravimetric analysis, and X-ray diffraction spectroscopy were applied to characterize the nanoadsorbent. Under the optimum conditions (pH = 5, contact time = 15 min, temperature = 30°C, and initial nonylphenol concentration = 20 mg L–1), the developed technique shown the excellent reusability. Within the 5th cycle, the adsorption potential of recycled nanoadsorbent was restored by nearly 90% and this percentage decreased to 60% in the 8th cycle. The adsorption data fitted well with the Langmuir isotherm model (R2 = 0.9927) and pseudo-second-order kinetic model (R² = 1). The obtained nanoadsorbent possess the highest sorption capacity (43.47 mg g–1). Recoveries, at 1 µg mL–1 concentration level, ranged from 89% to 98% with relative standard deviations lower than 5% (n = 3). The results of nonylphenol removal from the environment samples shown the great applicability of nanoadsorbent for the removal of nonylphenol. [ABSTRACT FROM AUTHOR]

Novel wound dressing materials are required to non-cytotoxic with a viable cell ratio of above 92%. Herein, the cytotoxicity of hyaluronic acid/chitosan/bacterial cellulose-based (BC(CS/HA)) membranes are evaluated and compared to that of alginate/chitosan/bacterial cellulose-based (BC(CS/Alg)) membranes was investigated. Multilayer membranes with up to ten CS/HA or CS/Alg layers were prepared using the layer-by-layer (LBL) method. Scanning electron microscopy showed that the diameters of the fibers in the BC(CS/Alg) and BC(CS/HA) membranes were larger than those in a BC membrane. The cytotoxicity was analyzed using BALB-3T3 clone A31 cells (mouse fibroblasts, 1 × 104 cells/well). The BC(CS/HA)5 and BC(CS/HA)10 membranes exhibited high biocompatibility, with the cell viabilities of 94% and 87% at 5 d, respectively, compared to just 82% for the BC(CS/Alg)5 and BC(CS/Alg)10 membranes with same numbers of layers. These results suggested that BC(CS/HA)5 is a promising material for wound dressings.

The lack of precise equilibrium gas permeability affects the application of edible coatings. This study aims to precisely control the coating oxygen permeability through layer-by-layer (LbL) assembly. The coatings fabricated by chitosan (CS) and sodium alginate (SA) were systematically investigated about assembly mechanism, growth law, barrier performance, and application. Results showed that coating assembly was driven by the electrostatic interaction between CS and SA. The fastest coating growth was the pH of SA and CS at 4 and the NaCl concentration at 0.1 mol/L. The coating with a specific barrier performance had been proved to be accurately fabricated by adjusting the assembly concentration and times. Finally, coating combinations with the desired oxygen-barriers for strawberries, tangerines, and bananas were predicted based on the gas exchange model and fabricated by LbL. The physiological properties of the coated fruits indicated that the optimal LbL coating extended the shelf life of strawberries, tangerines and bananas by 2, 4, and 4 days, respectively. This research may help to precisely control the properties of coatings during the preparation and application of edible coatings. [ABSTRACT FROM AUTHOR]

A film with "brick-and-mortar" structure was prepared by layer-by-layer (LBL) technique using polyvinyl alcohol (PVA) and polymethyl methacrylate (PMMA) as the flexible material or "mortar" and mica as the rigid material or "brick". The film deposited on a glass slide after self-assembly cycles had a thickness of 3 µm thick and an uneven, wavy surface. The film exhibits enhanced mechanical properties, i e, the hardness and indentation modulus values could reach 6.14 and 68.41 GPa, respectively. The hardness and elastic toughness were found to be depended on three factors, i e, the ratio of PVA to mica, the number of self-assembly cycles, and the pretreatment method of the mica suspension. The self-assembly process was driven by formation of the hydrogen bonds between the silanol groups of mica and the hydroxyl groups of PVA and carbonyl groups of PMMA. [ABSTRACT FROM AUTHOR]

A novel modification to the traditional layer by layer process that adds three-dimensional control to the technique is introduced. In this modification to the process, the substrate is irradiated with laser light during the polycation and/or polyanion dipping cycles. An array of PAH/PCBS polymer thin films were fabricated using the laser modified approach with varied bilayer numbers, laser powers, and laser irradiation times. The modification was conducted with a semiconductor laser with powers from 1.1 to 5.5 W at 450 nm. Surface profilometry results show a change in height of more than 500 nm for a 55 bilayer PAH/PCBS thin film. For 25 bilayer films, the addition of laser modification during the PAH cycle leads to a reduction in absorbance of up to 54% compared to the areas not being irradiated. The absorbance at 365 nm associated with PCBS shows a nonlinear relationship with bilayer number, in contrast to the usual linear relationship between absorbance and bilayer without laser irradiation. By adjusting irradiation time, irradiation power, number of bilayers, and the location of irradiation, a variety of structures with controlled thicknesses can be fabricated. [ABSTRACT FROM AUTHOR]

Despite rapid advances in the field of organic solar cells (OSCs), high‐performance large‐scale OSC modules are limited. In this study, it is found that the non‐Newtonian fluid feature of conjugated polymer primarily causes the wedge‐shaped mass (donor and/or acceptor component)/phase distribution of blends in large‐scale blade coating, which results in the lower module efficiency. To address the critical issue in printing manufacturing, a reversible and sequential layer‐by‐layer (RS‐LBL) deposition method with sequential twice forward/reverse blade‐coating of polymer donor and forward blade‐coating of Y6 acceptor, is developed for precisely controlling fluid mechanics of PM6:Y6 active layer. Through using the RS‐LBL strategy, uniform morphology and favorable phase separation and crystallization are obtained in the 10 × 10 cm2 active layer. As a result, the RS‐LBL‐based OSCs show excellent operational stability, and an outstanding PCE of 13.47% is achieved with significantly suppressed charge recombination losses in the 36 cm2 large‐area OSC module, which represents the highest efficiency of binary solar modules with the area over 30 cm2. This study provides a feasible route for the next generation of high‐performance large‐area OSCs and OSC modules. [ABSTRACT FROM AUTHOR]

Microfluidic Electrochemical biosensors present promising means for many critical biosensing applications such as neurotransmitter monitoring, pathogen detection, and molecular diagnostics. However, such biosensors are prone to many challenges like enzyme degradation being the major concern with electrode materials while testing multiple times, hindered detection limit range, low sensitivity due to direct contact of enzyme with the environment, and poor shelf life of the electrodes patterned by conventional techniques. Herein, a microfluidic multi-sensitive biosensor is developed using a layer-by-layer process, incorporating a novel Laccase/MXene/LIG (L-Ti3C2-G) composite designed for selective detection of dopamine and other biochemicals with applicability in human blood serum and synthetic urine. 2D nano-material, MXene, gave an excellent conductivity, more volumetric capacity, flexibility, surface hydrophilicity, and temperature stability, leading to its use in various applications. It was found that laccase immobilized electrode (L-Ti3C2-G) showcased a significant electrocatalytic activity towards biomolecules such as uric acid (0.12 V), L-cysteine (0.62 V), xanthine (0.7 V), ascorbic Acid (0.1 V), and dopamine (0.42 V). For dopamine alone, the proposed biosensor exhibits a LOD of 0.47 nM with a linear concentration range of 1 nM – $10~\mu \text{M}$ and 6.37 mA nM−1 cm−2 sensitivity. Moreover, real sample analysis indicated that spiked dopamine can be determined accurately by the electrode with a recovery ratio of more than 97% in synthetic urine and human blood serum samples. The fabricated bioelectrode had high stability and reproducibility with an exceptional selectivity and negligible interference with various biochemicals. [ABSTRACT FROM AUTHOR]

Layer-by-layer self-assembly of polyelectrolytes is one of the most promising methods for preparing nanofiltration membranes. Here poly (sodium 4-styrenesulfonate) (PSS) and poly (diallyldim-ethylammonium chloride) (PDADMAC) were chosen to prepare polyelectrolyte multilayer (PEM) membrane. The effects of background salt concentration, PSS concentration, background salt types, the number of layers and the outermost functional groups on the separation performance of the PEM were investigated systematically. Molecular dynamic simulation was employed to simulate the influence of background salt on the diffusion of PDADMAC. The simulation results agree well with the experimental results. The optimized (PSS/PDADMAC) 4.5 membrane with Na 2 SO 4 as background salt shows permeance of 15.9 LMH/bar, Na 2 SO 4 rejection of 98.2 %, and an excellent stability. Our study provides both theoretical and experimental supports for the preparation of PEM membranes using LBL method. [Display omitted] • Affecting factors were systematically investigated for polyelectrolyte membrane prepared by layer-by-layer self-assembly. • MD simulation results show that different ions influence the diffusion rate of polyelectrolyte. • The obtained membrane shows excellent separation performance for corresponding salts. [ABSTRACT FROM AUTHOR]

Due to their extraordinary prospective uses, particularly in the areas of oil–water separation, underwater superoleophobic materials have gained increasing attention. Thus, artificial nacre has become an attractive candidate for oil–water separation due to its superhydrophilicity and underwater superoleophobicity properties. Synthesized artificial nacre has successfully achieved a high mechanical strength that is close to or even surpasses the mechanical strength of natural nacre. This can be attributed to suitable synthesis methods, the selection of inorganic fillers and polymer matrices, and the enhancement of the mechanical properties through cross-linking, covalent group modification, or mineralization. The utilization of nacre-inspired composite membranes for emerging applications, i.e., is oily wastewater treatment, is highlighted in this review. The membranes show that full separation of oil and water can be achieved, which enables their applications in seawater environments. The self-cleaning mechanism’s basic functioning and antifouling tips are also concluded in this review.

Two addition orders, i.e., the layer-by-layer (L) and mixed biopolymer (M) orders, were used to generate sodium caseinate - sugar beet pectin electrostatically stabilized o/w emulsions with 0.5% oil and varying sodium caseinate: sugar beet pectin ratios (3:1-1:3) at pH 4.5. Emulsion stability against environmental stresses (i.e., pH, salt addition, thermal treatment, storage and in vitro simulated gastrointestinal digestion) and its astaxanthin encapsulation against degradation during storage and in vitro digestion were evaluated. Results indicated that a total biopolymer concentration of 0.5% was optimal, with the preferred sodium caseinate-sugar beet pectin ratios for L and M emulsions being 1:1 and 1:3, respectively. L emulsions generally exhibited smaller droplet diameters than M emulsions across all ratios, except at 1:3. Lowering the pH to 1.5 substantially reduced the net negative charge of all emulsions, with only L emulsions precipitating at pH 3. M emulsions showed greater tolerance to salt addition, remaining stable up to 500 mM sodium and calcium concentrations, whereas L emulsions destabilized at levels exceeding 50 mM and 30 mM, respectively. All emulsions were stable when heated at 37 °C or 90 °C for 30 min. Astaxanthin degradation rates increased with prolonged storage, reaching 61.66% and 54.08% by day 7 for L and M emulsions, respectively. Encapsulation efficiency of astaxanthin in freshly prepared M emulsions (86.85%) was significantly higher compared to L emulsions (72.82%). M emulsions had 30% and 25% higher encapsulation efficiency of astaxanthin than L emulsions after in vitro digestion for 120 min and 240 min respectively. This study offers suggestions for interface design and process optimization to improve the performance of protein-polysaccharide emulsion systems, such as in beverages and dairy products, as well as their delivery effect of bioactives., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Osteoporosis is the most common cause of fractures in middle-aged and elderly people. Fracture repair can be difficult due to the decreased bone volume in osteoporosis patients and implants are often required. In this study, a slow-release system for microstructured titanium (Micro-Ti) was designed to promote osteogenesis and inhibit osteoclastogenesis. Firstly, Micro-Ti was prepared on titanium surfaces by dual acid etching. Micro-Ti was covered with naringin (NA), chitosan (CHI) and gelatin (GEL) multilayers through layer by layer technique, which is denoted as LBL (NA) coated-Ti. Osteoblasts (ME3T3-E1) and macrophages (RAW 264.7) were cultured on untreated and treated titanium surfaces in vitro. Osteoblasts grown on LBL (NA) coated-Ti showed higher alkaline phosphatase (ALP) and mineralization, consistent with qRT-PCR analysis of osteoblast genes including runt-related transcription factor 2 (Runx2), ALP, collagen I (Col I), osteocalcin (OCN), osteopontin (OPN), and osteoprotegerin (OPG). In contrast, acid tartarate-resistant phosphatase activity and the expression of osteoclastic differentiation related genes comprising of cathepsin K (CTSK), nuclear factor of activated T cells (NFAT), tartrate resistant acid phosphatase (TRAP) and V-ATPase (VATP) in osteoclasts were significantly reduced on LBL (NA) coated-Ti surfaces compared with other groups. These results indicate that microstructured titanium functionalized by naringin inserted multilayers enhanced the differentiation of osteoblasts and inhibited osteoclast formation. The proposed approach in this research provides a novel way to modify titanium-based implants for fracture repair in osteoporosis patients. [ABSTRACT FROM AUTHOR]

Among mucosal administration routes for vaccines, the sublingual route has been proven capable of inducing a potent systemic and mucosal immune response. However, the absence of a simple and compliant delivery system and the lack of robust mucosal adjuvants impede the development of sublingual vaccines. Here, we describe a mucoadhesive patch made of a layer-by-layer assembly of polysaccharides, chitosan, and hyaluronic acid. The mucoadhesive patch was covered by adjuvanted nanoparticles carrying viral proteins. We showed that the nanoparticles effectively cross the outer layers of the sublingual mucosa to reach the epithelium. Furthermore, the encapsulated adjuvants, 3M-052 and mifamurtide, targeting toll-like receptor (TLR) 7/8 and nucleotide-binding oligomerization domain-2 (NOD2), respectively, remain fully active after encapsulation into nanoparticles and exhibit a cytokine/chemokine signature similar to the mucosal gold-standard adjuvant, the cholera toxin. However, the particulate adjuvants induced more moderate levels of proinflammatory interleukin (IL)-6 and keratinocyte chemoattractant (KC), suggesting a controlled activation of the innate immune response.

Alginate hydrogels can be used to develop a three-dimensional environment in which various cell types can be grown. Cross-linking the alginate chains using reversible ionic bonds opens up great possibilities for the encapsulation and subsequent release of cells or drugs. However, alginate also has a drawback in that its structure is not very stable in a culture medium with cellular activity. This work explored the stability of alginate microspheres functionalised by grafting specific biomolecules onto their surface to form microgels in which biomimetic microspheres surrounded the cells in the culture, reproducing the natural microenvironment. A study was made of the stability of the microgel in different typical culture media and the formation of polyelectrolyte multilayers containing polylysine and heparin. Multiple myeloma cell proliferation in the culture was tested in a bioreactor under gentle agitation.

Curcumin is a potential candidate in cancer therapy due to its ability to inhibit many signalling pathways at the same time of exposure because of its unique content of aromatic ring, B diketone, olefinic linker, and O methoxy phenolic groups. Its applications in biomedical therapy is limited because of its sensitivity, and its rapid degradation. In the current study, curcumin inserted into polyelectrolyte pairs (protamine and dextran) and then was functionalized by folic acid conjugated chitosan used for the first time, as theranostic system. Such this strategy allows to improve its mucoadhesion and penetration that increases their accumulation inside cancer cells. CUR-LbL NPs were then used to investigate drug release inside Human Mammary Carcinoma (MCF-7 cell lines) after their incubations for 3 h, 6 h and 24 h. Flow cytometry indicated that the percentages of apoptosis, necrosis and cell cycle arrest were increased significantly in MCF-7 cell lines treated by CUR-LbL NPs. Furthermore, SEM image showed many debris in the section of MCF-7 treated by CUR-LbL NPs. Here, it can be summarized that curcumin functionalized by multi-layered polyelectrolyte capsules can be used as a model to study the fate of the adsorbed nanocarriers and to investigate the drug release inside cells. Scheme 1: Stack images showed Z dimension in design of XYZ to identify the depth location of drug internalization, drug release and the fate of nanocarriers after drug release. [Display omitted] • Curcumin can be used as a good model to study cellular uptake and drug release. • Layer by Layer technique is a promising strategy used for designing optimal targeted capsules. • Z stack used to study drug release and fate of nanocarriers after drug release. • RhB-Nanocarriers were adhered to inner face of cell membrane after drug release. • Curcumin is a potential candidate can be used in cancer therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • pH-responsive smart zeolite has been successfully developed by hydrothermal and LBL routes. • The smart coating with 5% smart zeolite has optimal anticorrosive performance. • MBT molecules could be passivated on steel to form a corrosion protection effect. • The dispersible smart zeolite pigments improve the barrier effect of coatings. • Zeolite pigments were added to enhance the long-term protection of coatings. The process for the synthesis of smart zeolite is complex. The porous zeolite was synthesized by a hydrothermal route. Aluminium powder and tetraethyl orthosilicate (TEOS) are used as alumina and silica sources. The presence of tetrapropylammonium hydroxide (TPAH) and sodium dodecyl benzene sulphonic acid (SDBS) acts as a structural directing agent and soft templates. The chemical growth mechanism of porous zeolite to form needle structures with the help of templates is discussed. The porous zeolite was prepared using optimum crystallization conditions (temperature and duration) and Si/Al component ratios. Following calcination, the porous zeolite was loaded with mercaptobezothaizole (MBT) and layer by layer (LBL) covered with both cationic and anionic polyelectrolytes. This is the first time a study has been conducted that embraces the porous zeolite pre-loaded with a corrosion inhibitor (MBT). Here, the MBT is released in high pH conditions to prevent corrosion, simultaneously increasing the life of the smart zeolite coatings in a corrosive environment. The smart zeolite-based coatings prevent corrosion by the pH activity of smart zeolite above the neutral pH condition. [ABSTRACT FROM AUTHOR]

Abstract TiO2, ZrO2 and layer-by-layer TiO2–ZrO2 films were prepared by doctor blade method followed by sensitization with natural dye for dye-sensitized solar cell application. The structural and optical, morphological and compositional properties were investigated by X-ray diffraction and UV–Vis spectroscopy, scanning electron microscopy, BET, surface profilometer and energy-dispersive X-ray analyzer, respectively. Dye-sensitized solar cells were fabricated using the prepared electrodes of TiO2, ZrO2 and layer-by-layer TiO2–ZrO2 films sensitized with natural dye extracted from Pandan leaves (Pandanus amaryllifolius). The J–V characteristics were recorded to measure photo-response of fabricated devices and electrochemical impedance spectroscopy to study the electron behavior, series resistance and lifetime. Photovoltaic parameter like short-circuit current, open-circuit voltage, fill factor, and power conversion efficiency were evaluated for fabricated solar cell under artificial light supplied from white LED (15 mW·cm−2). The average values of power conversion efficiency of DSSCs fabricated with TiO2, ZrO2 and layer-by-layer TiO2–ZrO2 photoanodes were found to be 0.65%, 3.04% and 3.13%, respectively.

In this work, layer by layer (LbL) thin film nanocomposite (TFN) membranes were prepared and used as pervaporation membranes to separate methyl tertiary butyl ether (MTBE)/methanol (MeOH) mixture. TFN membranes, comprising of carbon nanotubes (CNT), were prepared by interfacial polymerization (IP) of m-phenylenediamine (MPD) and trimesoyl chloride (TMC) monomers on the porous polyethersulfone/polyethylene glycol (PES/PEG) sublayer. Carbon nanotubes were functionalized by ethylenediamine (EDA) and incorporated into the polyamide (PA) layer at 0.01–0.04 wt.% loadings. After that, the surface roughness, surface hydrophilicity, and morphology of the resulting membranes were characterized. Also, the effect of the sequence of reactants deposition and concentrations of the nanotubes on the membrane performance were investigated using pervaporation of MTBE/MeOH under feed temperature and feed flow rate of 30 °C and 4 L.h-1, respectively. The pressure of permeate-side was about 100 mbar. Obtained results showed that both separation factor and permeation flux of LbL TFN membranes increased by adding CNT into the PA layer up to 0.02 wt.%. By increasing CNT loading to 0.04 wt.%, the separation factor decreased from 106 to 77.6, while permeation flux increased from 0.56 to 0.81 kg.m-2.h-1. It should be noted that, in the single-layer membrane, the separation factor decreased from 73.2 for TFC membrane to 56.4 for TFN membrane with increasing the CNT loading from the beginning. According to these results, LbL TFC and TFN membranes are expected to be the next generation of high-performance PV membranes. [ABSTRACT FROM AUTHOR]

A graphene oxide/chitosan polyelectrolyte layer was used to modify the surface of a polyvinyl alcohol/tetraethyl orthosilicate membrane by layer-by-layer interfacial complexation and, thus, improve the pervaporation characteristics. The interfacial complexation between the chitosan and graphene oxide was confirmed by Fourier-transform infrared and X-ray photoelectron spectroscopy; the changes in surface hydrophilicity after layer-by-layer modification were examined by contact angle measurements, and the morphology of the layer-by-layer membrane was elucidated by field-emission scanning electron microscopy analysis. The pervaporation performance of the modified membranes was evaluated by performing the separation of water-isopropanol (IPA) azeotropes under different operating conditions. In the pervaporation experiments, the best performance was obtained using a membrane with 15 chitosan-GO layers (denoted 15L-L(CH-GO)). For this membrane, the flux increased from 13.6 to 76.4 g/m2h and the separation factor decreased from 56,720 to 4,001 as the feed temperature was varied from 30 to 60 °C for an 80: 20 (w/w) IPA/water feed. The apparent permeation activation energies were calculated and that of IPA (122.8 kJ/mol) was greater than that of water (47.4 kJ/mol). [ABSTRACT FROM AUTHOR]

A unique microfluidics approach for functional hydrogel patterning with multilayered heterogeneous structures is presented. Prepolymer solution droplets with differentiated sodium acrylate concentrations are dispensed/printed in a wetting‐controlled "two‐parallel plate" (TPP, like a Hele‐Shaw Cell) system. The gelation within the system enables hydrogel bilayer structures with reconfigurable 3D deformations driven by in‐plane and through‐thickness heterogeneity under stimuli‐responsive mask‐less swelling/deswelling. The cooperation between swelling mismatch of functional groups results in a higher complexity of 3D reconfiguration in responding to discrete levels of stimulation inputs. This facile patterning technology with an in‐built ionic hierarchy can be scaled up/down with advanced transducing functionalities in various fields. [ABSTRACT FROM AUTHOR]

Exposure to ionizing radiation (IR) during diagnostic medical procedures brings certain risks, especially when experiencing recurrent exposures. The fabrication of nano-based composites, doped with different nanoparticles, have been suggested as effective shielding materials to replace conventional lead-based ones in material sciences and nanotechnology. In this study, commercially available fabrics, used to produce scrubs and gowns for clinical staff, are modified utilizing graphene oxide (GO) nanoparticles using a layer-by-layer (LBL) technique. GO was obtained from graphite through environmentally friendly technology by using a modified–improved Hummers’ method without NaNO3. Lightweight, flexible, air- and water-permeable shielding materials are produced that are wearable in all-day clinical practice. The nanoparticles are kept to a minimum at 1 wt%; however, utilizing the LBL technique they are distributed evenly along the fibers of the fabrics to achieve as much shielding effect as possible. The evaluation of samples is accomplished by simulating real-time routine clinical procedures and the radiographic programs and devices used daily. The GO-coated nanocomposite fabrics demonstrated promising results for X-ray shielding.

Poly(3,4‐ethylenedioxythiophene (PEDOT) derivatives display a multitude of attractive properties such as high conductivity, biocompatibility, ease of functionalization, and high thermal stability. As a result, they show promise for applications in materials and biomedical engineering. In order to increase their applications in the practical domain, trivial fabrication techniques are required. Here, we present a simple layer‐by‐layer dip methodology to assemble water‐soluble PEDOT derivatives that can then be disassembled via electrical stimulation. As a result, a dynamic PEDOT layered system is fabricated and could be applied as responsive materials for bioengineering. PEDOT‐SO3 and PEDOT‐NMe3 are synthesized via direct C‐H arylation polymerization and chemical polymerization, respectively. The electrostatic interactions between oppositely charged SO3− and NMe3+ enabled the stacking of PEDOT derivatives. The layer‐by‐layer assemblies are confirmed by ultraviolet–visible spectroscopy and profilometer. Morphological analyses are performed using scanning electron microscopy and atomic force microscopy, which revealed that the polymer coatings are uniform without any cracks. In situ material assembly is studied using quartz crystal microbalance, and we also demonstrate that these PEDOT‐derivative assemblies can be disintegrated by electrical stimulation. Cyclic voltammetry shows a proportional increase in stored charge density with the increase in bilayer thickness, confirming stable electroactivity of these assemblies. Using this approach, we can assemble conductive bio interface on both conductive and nonconductive surfaces, expanding the capability to fabricate bioelectronic electrodes. [ABSTRACT FROM AUTHOR]

The aim of this research is to capsulate methadone (MTD) in polymeric layers based on layer by layer method. Fe3O4 nanoparticles (NPs) were synthesized by polyethylene glycol and modified by folic acid. MTD was conjugated to NPs and polymeric layers surrounded this nano-system. Percentage of loaded MTD, in vitro release and kinetic factors were studied. The average size of the prepared NPs was 23 nm. The surface potential of the capsule was changed from +39 to −27 mV for chitosan and alginate, respectively. In this study, a nano-system was designed to decrease methadone release rate. In vitro study indicated that MTD release was slow enough and controllable. By this designed nano-system, addicts can consume this nano-drug just two times a week. [ABSTRACT FROM AUTHOR]