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Stimuli-responsive polysulfone (PSf) ultrafiltration (UF) membrane was developed via surface modification with tethered hydrophilic polyacrylic acid (PAA) chains of length greater than the native membrane pore size. The surface nano-structured (SNS) membrane was synthesized via atmospheric pressure plasma-induced graft polymerization (APPIGP) to form a surface tethered PAA brush layer. The SNS-PAA-PSf UF membrane demonstrated hydraulic permeability and selectivity in the ranges of 0.74–2.29 × 1013 m−1 and 1.8–15.0 kDa, respectively, in response to changes in pH (3–11) and ionic strength (~0.02–547 mM). Membrane performance characterization showed that, for the above ranges of pH and salinity, the SNS-PAA-PSf UF membrane can overcome the typical membrane perm-selectivity tradeoff. The above performance is attributed to the swelling of the tethered PAA chains, upon ionic strength decrease or pH increase, which provides a less hindered transmembrane solute transport path, but increased hydraulic resistance. Conversely, at high ionic stress or low pH tethered chain collapse leads to lower molecular weight cutoff (MWCO) but with hydraulic resistance below that of the swollen state. The study results suggest that there is merit for further tailoring and improving the performance of stimuli-responsive UF membranes, developed via APPIGP, for applications over selected ranges of pH and ionic strength. [ABSTRACT FROM AUTHOR]

Different pyrrole and allylamine polymeric materials, were synthesized by plasma polymerization with different powers and doped with iodine. The polymers were characterized physicochemically. A cell line of neuronal origin (N1E-115) was cultured on them to evaluate the effects of the materials on neuronal differentiation. Following a differentiation stimulus, immunofluorescence was performed, and the lengths of neurites, as well as the complexity of the network formed and the number of nuclei, were measured and analyzed to provide a differentiation index. The results showed that the polymeric materials exhibited different physicochemical characteristics depending on the synthesis conditions and enhanced neuronal differentiation. [ABSTRACT FROM AUTHOR]

ABSTRACT Antibacterial polymeric coatings are deposited on polyethylene terephthalate (PET) films through atmospheric pressure plasma polymerization with pentane and hexane monomers. The process uses surface dielectric barrier discharge in nitrogen. XPS analysis reveals the formation of carbon‐ and nitrogen‐containing films with oxygen incorporation from ambient air. Alkyl, hydroxyl, and amine groups contribute to the coatings' superhydrophilic properties post‐treatment. Coating thickness varies with the monomer flow rate, with pentane yielding thicker coatings than hexane under identical conditions and deposition increasing linearly with the flow rate. Treated PET films show strong antibacterial activity against Staphylococcus Aureus and Escherichia coli, demonstrating plasma polymerization's potential in biomedical applications. Cytotoxicity, evaluated using the MTS assay, confirms biocompatibility. [ABSTRACT FROM AUTHOR]

This study investigates the enhancement of linear low‐density polyethylene (LLDPE) nanocomposites with multiwalled carbon nanotubes (CNT) at concentrations of 1, 3, and 6% w/w. To improve the interfacial interaction between the CNT and the polymeric matrix, CNT were treated using ethylene cold plasma (P‐CNT) in a rotary reactor. The incorporation of CNT into the polymer was carried out by a melt mixing process (MMP) and a sequential ultrasound dispersion method followed by melt mixing (UDM‐MMP). The thermal stability of nanocomposites with 6% P‐CNT increased by 45°C compared to pristine LLDPE. Electrical conductivity reached 2.5 × 10−2 S/cm for nanocomposites with 6% CNT. The elastic modulus increased from 519.52 MPa (LLDPE) to 714.63 MPa (6% CNT) and 795.43 MPa (6% P‐CNT), which further improving to 731.42 MPa (6% CNT) and 841.27 MPa (6% P‐CNT) using UDM‐MMP. Additionally, yield stress rose from 16.35 MPa to 21.28 MPa (6% CNT) and 22.06 MPa (6% P‐CNT), reaching 21.47 MPa and 22.28 MPa with UDM‐MMP. Tensile strength increased from 21.31 MPa to 25.15 MPa (6% CNT) and 25.9 MPa (6% P‐CNT), achieving 26.82 MPa (6% P‐CNT) with UDM‐MMP. These results highlight a significant improvement in conductivity, rigidity, and mechanical strength, emphasizing their potential for advanced applications. [ABSTRACT FROM AUTHOR]

Paper finishing, in particular, coating paper with desired barrier functions is well‐developed as of today. However, due to large amounts of material and process energy as well as the use of non‐renewable resources for such coatings, common technologies are not sustainable. Given the increasing importance of paper in manifold applications, more sustainable routes with low‐energy processes as well as biogenic material alternatives are highly needed. To address this challenge, a solvent‐free and material‐efficient approach is proposed to bio‐based paper coatings by depositing chia oil‐based plasma polymers using a jet‐induced sliding discharge concept at atmospheric pressure. Depending on the amount of coating and the paper porosity, this treatment retards water absorption. Coating visualization is enabled through confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Like chia oil, safflower oil, and olive oil show the ability to hydrophobize paper and the great potential within plasma polymerized vegetable oils to make the paper coating more sustainable. [ABSTRACT FROM AUTHOR]

The electrophoretic deposition of multi‐walled carbon nanotubes (MWCNTs) has been well‐researched; however, preparatory steps lead to MWCNT coating contamination and deposits often have weak adhesion to the substrate. This work targets these two weaknesses. First, MWCNTs were functionalized by nonthermal, radiofrequency plasma, producing oxygenated MWCNTs (O‐MWCNTs), with which water‐based suspensions were prepared. Second, an ethane‐based plasma polymer was applied on the metallic substrate as an interlayer to improve coating adhesion. O‐MWCNT coatings were produced at 5–40 V for 1–60 min. Homogeneous coatings with thicknesses up to 10 µm were achieved, the composition was 90‐95 at% carbon with the balance element being oxygen, and coating adhesion without damage was confirmed for shear stresses up to 16 Pa. [ABSTRACT FROM AUTHOR]

This work aims to investigate the influence of the substrate temperature on low‐pressure plasma polymerization processes. Emphasis is placed on the mechanical properties and growth mechanism of the plasma polymer films (PPFs). For this purpose, two precursors are considered, differing only by their unsaturation degree: 2‐propen‐1‐ol (CH2═CH–CH2–OH) and propan‐1‐ol (CH3–CH2–CH2–OH). Although propan‐1‐ol‐based PPFs behave like hard elastic solids, 2‐propen‐1‐ol‐based coatings evolve from a liquid film to an elastic solid on increasing the substrate temperature. This behavior is understood considering the evolution of the glass transition temperature of PPFs. The latter is correlated with the cross‐linking degree of the polymeric network governed by the energy density of bombarding ions on the growing film. [ABSTRACT FROM AUTHOR]

The achievement of large-scale applications of plasma-based polymers in biomedical sectors does not satisfy the appropriate level although a substantial amount of research is already performed. In this context, further investigations are necessary to design and synthesize plasma polymers for biomedical applications. Among the polymeric materials, plasma-based polymers have attracted substantial attention owing to their numerous advantages like faster processing, lower costs, eco-friendly waste, biocompatibility, and versatility, making them excellent materials for biomedical applications. Further, polymer synthesis using plasma polymerization techniques can avoid the time-consuming conventional multistep synthesis procedure. Plasma polymerization also offers a significant solution to overcome the numerous difficulties in the traditional approach where polymers can be directly attached to the desired surface using a plasma process, without disturbing the growing chain, and, thus, prevent an additional process such as grafting. Nevertheless, the design of appropriate plasma-based synthesis methods, optimization of the plasma process parameters, and exploration of polymer-based biocompatibility approaches are still challenging research areas. Regarding the surface morphological features of these plasma polymers, they possess several characteristics, such as wettability, adhesion capacity, and so on, that are important considerations in biomedical applications. In this review, numerous recent approaches to plasma polymerization methods along with different precursor phases used for such kind of synthesis of polymeric materials are discussed. The morphological aspect of the synthesized plasma polymers connected with biomedical applications is also reported in this review. Finally, promising aspects of plasma polymers for biomedical applications are briefly reported in this work. This review may offer an extensive reference for upcoming perceptions of plasma-based polymers and their applications in biomedical sectors. [ABSTRACT FROM AUTHOR]

This work compared C4F8 and C4H2F6 gases (as third components in CF4 + He gas mixture) for the high aspect ratio etching of SiO2 through the amorphous carbon layer (ACL) mask. The research scheme included the study of gas‐phase plasma characteristics, etching kinetics, and etching profiles. It was found that CF4 + C4F8 + He and CF4 + C4H2F6 + He gas mixtures are featured by quite close plasma parameters, the kinetics of electron‐impact processes, and ion bombardment intensities. At the same, the use of C4H2F6 provides a bit lower F atom density together with a bit higher polymerizing ability. All these factors cause lower absolute etching rates for both SiO2 and ACL but provide better SiO2/ACL/ACL selectivity and profile features. [ABSTRACT FROM AUTHOR]

A recent in vivo study [Kodama et al., Sci. Rep. 11, 1 (2021)] showed that porous artificial bones coated with amine-containing polymers deposited by plasma-enhanced chemical vapor deposition (PECVD) significantly enhanced bone regeneration. This article reports the chemical and physical properties of amine plasma polymers (PPs) formed under the same deposition conditions, including the film stability for up to two months, the effects of sterilization on the chemical compositions of the films, and the penetration of amine PPs into the inner surfaces of interconnected microscopic pores of the amine PP-coated porous artificial bone. It was found that, immediately after the plasma polymerization process, approximately 20% of nitrogen atoms on the surface of the deposited amine PP formed primary amines. However, the value decreased to approximately 5% over one month if the sample was exposed to ambient air. The relative concentration of primary amines also decreased to a similar value after the sample was sterilized by autoclaving or ethylene oxide gas. Molecular dynamics simulations were used to examine possible formation mechanisms of nitriles in deposit films under the PECVD conditions and found that ion impact can significantly reduce the nitrile content. [ABSTRACT FROM AUTHOR]

Molecularly imprinted polymers (MIPs) are synthetic polymers that mimic the functions of antibodies. Though MIPs are promising tools in various areas, achieving high selectivity in MIPs can be difficult. To improve selectivity, various approaches have been implemented; however, the role of polymerization methods or synthetic techniques in enhancing the selectivity of MIPs has not been studied and remains a crucial area for further research. MIPs are typically prepared from free radical reactions. Recently, we found that Dielectric Barrier Discharge (DBD) plasma can be used to initiate the polymerization of vinyl monomers. The DBD plasma method allows the monomers to associate with the template molecules and initiate polymerization with minimal disruption to the positioning of the monomers. We hypothesize that this could be a preferred method to prepare MIPs over the traditional radical reaction that may cause a disturbance of the pre-associated monomers on the templates for the polymerization. Chicken egg white serum albumin (CESA) was used as the template protein for the MIPs. Our results show that in all test conditions, approximately twofold improvement in selectivity was achieved, which is the primary performance metric for MIPs. This enhancement was evident across all categories, including MIPs prepared from various monomer combinations. [ABSTRACT FROM AUTHOR]

This study investigates the measurement of plasma‐grown nanoparticles, comparing ex situ scanning electron microscopy (SEM) and an in situ light scattering method which is based on Mie theory and utilizes a neural network for evaluation. The research reveals that the particle size distribution (PSD) is normal and very narrow, supporting the common assumption of monodisperse particle clouds. Importantly, the study finds that the spread of the PSD increases proportionally with the mean size, suggesting varied growth rates based on the radius of the spherical dust grains. Both methods produce consistent results, which encourages the use of the interference‐free, real‐time, light‐based Mie method in similar studies. [ABSTRACT FROM AUTHOR]

Macropinocytosis is a broadly conserved endocytic process discovered nearly 100 years ago, yet still poorly understood. It is prominent in cancer cell feeding, immune surveillance, uptake of RNA vaccines and as an invasion route for pathogens. Macropinocytic cells extend large cups or flaps from their plasma membrane to engulf droplets of medium and trap them in micron-sized vesicles. Here they are digested and the products absorbed. A major problem -- discussed here -- is to understand how cups are shaped and closed. Recently, lattice light-sheet microscopy has given a detailed description of this process in Dictyostelium amoebae, leading to the 'stalled-wave' model for cup formation and closure. This is based on membrane domains of PIP3 and active Ras and Rac that occupy the inner face of macropinocytic cups and are readily visible with suitable reporters. These domains attract activators of dendritic actin polymerization to their periphery, creating a ring of protrusive F-actin around themselves, thus shaping the walls of the cup. As domains grow, they drive a wave of actin polymerization across the plasma membrane that expands the cup. When domains stall, continued actin polymerization under the membrane, combined with increasing membrane tension in the cup, drives closure at lip or base. Modelling supports the feasibility of this scheme. No specialist coat proteins or contractile activities are required to shape and close cups: rings of actin polymerization formed around PIP3 domains that expand and stall seem sufficient. This scheme may be widely applicable and begs many biochemical questions. [ABSTRACT FROM AUTHOR]

Clarias species used in aquaculture are suffering from inbreeding depression with its attendant poor reproductive attributes and there is the need to explore the natural population to improve reproductive performance. Therefore, this work aimed at evaluating the morpho-genetic variability among wild and cultured Clarias garipinus available in Ogbomoso, South-Western, Nigeria. Fifty C. gariepinus samples were obtained from the wild and cultured populations and only ten were favoured for this work. The DNA was extracted from the caudal peduncles of five representatives of the two sampled populations and DNA amplification was done using cytochrome oxidase region's COX1. Predictive Analytics Software version 20.0 was used for data analyses. Results showed that virtually all morphometric parameters measured were significantly higher in the cultured populations compared to the wild except the dorsal fin length (p=0.346). The A260/280 ratio ranges from 1.85 (C1) to 2.11 (W2), with most samples having a ratio close to 2.0, indicating high-purity DNA, which is around standard recommended DNA concentration for the amplification. The DNA amplified at 700 bp from a portion of mitochondrial DNA (mtDNA) of wild and cultured Clarias gariepinus. The genetic distance between each strain is represented by the length of the branch that connects them. Therefore, these suggest that C. gariepinus breeders and farmers should source C. gariepinus species from the wild in order to genetically enrich the gene pool. Additionally, head region-based morphometric traits might be more informative in distinguishing wild and cultured populations of C. gariepinus. [ABSTRACT FROM AUTHOR]

Catalytic converters have now been largely employed to significantly reduce the levels of carbonbased particles into the atmosphere, however, this approach generates nanoparticles (NPs) that are often released as fine airborne particles into the atmosphere, having abilities to remain suspended in the atmosphere for long durations and find their way into the human lung cells, and eventually into the blood stream. This could result in triggering the body's innate immune system. In this study, we exposed blood samples from healthy individuals to Platinum nanoparticles and compared the results to the effects induced by the thrombogenic TiO2, to investigate the response mechanisms of the blood cells and innate immune system to these particles. Results showed a clear activation of coagulation system in samples treated with both NPs, compared with untreated blood samples. TiO2 NPs had significantly higher coagulation effect (84% platelet consumption) compared to the platinum NPs (38% platelet consumption), while blood samples without NPs showed only a 14% platelet consumption. Also, TiO2 NPs and Pt NPs induced slightly similar complement activation in blood samples as measured from the generated C3a (921±16.70 µg/L and 826±27.50 µg/L respectively) and sC5b-9 (136±3.46 µg/L and 138±6.49 µg/L respectively) components. However, blood samples without NPs exhibited significantly lower C3a and sC5b-9 components (522±22.50 µg/L and 101±4.70 µg/L respectively). The latter demonstrated the potential risks exposed to by urban dwellers, such as cascading inflammatory and thrombotic responses, there is need for more investigation on the patho-serological events that can be triggered by other airborne fine particles. [ABSTRACT FROM AUTHOR]

This study investigates the application of textile electrodes using PANI (Polyaniline) conductive material for motion sensing, specifically aimed at motion monitoring for the elderly. By depositing a PANI conductive layer on the base of warp-knitted fabric through in-situ polymerization and plasma treatment, a PCCWKF (Polyaniline Coated Conductive Warp-Knitted Fabric) with enhanced electrical conductivity and mechanical flexibility was developed. The research optimized the electrical resistivity and durability of PCCWKF by incorporating Polyvinyl Alcohol (PVA) as a toughening agent, improving the adhesion of the PANI conductive layer to the textile substrate. The sensor's efficacy in accurately recording and monitoring motion amplitude and frequency in real-time was demonstrated through its application in smart clothing, focusing on respiratory, elbow, and knee motion monitoring. This study holds significant implications for the advancement of wearable technology and smart textiles in the health monitoring of the elderly. [ABSTRACT FROM AUTHOR]

Insulating ceramics are widely used in power systems, but their high polarity makes them prone to wet and pollution flashover. In this paper, an Ar/polydimethylsiloxane dielectric barrier discharge excited by a parametric nanosecond-pulse power source is utilized for plasma polymerization to enhance ceramic surface insulating performance. Diagnosis of the discharge characteristics and surface physiochemical properties is conducted at different repetition frequencies to investigate the mechanism associated with the relationship between repetition frequency and the plasma polymerization process. The results indicate that a superhydrophobic surface can be achieved at repetition frequencies above 2 kHz. This transformation brings about multiple effects, including a decrease in surface polarity, an increase in charge dissipation, and an improvement in surface dry and wet flashover voltages. It is discovered that the discharge mode shifts from homogeneous to filamentary due to the memory effect of high repetition frequencies. Additionally, several filaments are generated simultaneously during a single pulse, facilitating the polymerization reactions. For high repetition frequencies, a low-polarity silicon-containing film with micro-nanometer structures is deposited on the ceramic surface, while scattered polymer fragments are generated on the surface without a cross-linked film for repetition frequencies below 2 kHz, despite longer treatment durations. [ABSTRACT FROM AUTHOR]

Atmospheric pressure plasma polymerization represents a promising coating technology, addressing drawbacks of traditional processes (solvent use, multistep procedures, etc.) while enabling deposition of thin cross‐linked polymer layers with high contour fidelity. We address technological challenges with a novel plasma device that integrates multiple plasma source benefits and investigate the suitability of two plant‐based precursors, chia and tung oil, for plasma polymerization to hydrophobize glass and paper. Chia oil enables the deposition of thin, covalently bonded hydrophobic polymer layers. Such coatings have diverse applications especially inside the paper industry, where water repellents in the form of internal and surface sizing have always been an essential functionalization step. Using bio‐based precursors and reducing extra chemicals contributes to substituting fossil‐based or harmful substances. [ABSTRACT FROM AUTHOR]

In this review, we introduce recently developed plasma-based approaches for depositing and treating piezoelectric nanoparticles (NPs) and piezoelectric polymer films for nanogenerator (NG) and sensor applications. We also present the properties and an overview of recently synthesized or modified piezoelectric materials on piezoelectric polymers to highlight the existing challenges and future directions of plasma methods under vacuum, low pressure, and ambient air conditions. The various plasma processes involved in piezoelectric NGs and sensors, including plasma-based vapor deposition, dielectric barrier discharge, and surface modification, are introduced and summarized for controlling various surface properties (etching, roughening, crosslinking, functionalization, and crystallinity). [ABSTRACT FROM AUTHOR]

In this study, the plasma graft polymerization technique was used to graft glycidyl methacrylate (GMA) onto polypropylene (PP) melt-blown fibers, which were subsequently aminated with N-methyl-D-glucamine (NMDG) by a ring-opening reaction, resulting in the formation of a boron adsorbent denoted as PP-g-GMA-NMDG. The optimal conditions for GMA concentration, grafting time, grafting temperature, and the quantity of NMDG were determined using both single factor testing and orthogonal testing. These experiments determined the optimal process conditions to achieve a high boron adsorption capacity of PP-g-GMA-NMDG. Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersion spectrum analysis (EDS), and water contact angle measurements were performed to characterize the prepared adsorbent. Boron adsorption experiments were carried out to investigate the effects of pH, time, temperature, and boron concentration on the boron adsorption capacity of PP-g-GMA-NMDG. The adsorption isotherms and kinetics of PP-g-GMA-NMDG for boron were also studied. The results demonstrated that the adsorption process followed a pseudo-second-order kinetic model and a Langmuir isothermal model. At a pH of 6, the maximum saturation adsorption capacity of PP-g-GMA-NMDG for boron was 18.03 ± 1 mg/g. In addition, PP-g-GMA-NMDG also showed excellent selectivity for the adsorption of boron in the presence of other cations, such as Na+, Mg2+, and Ca2+, PP-g-GMA-NMDG, and exhibited excellent selectivity towards boron adsorption. These results indicated that the technique of preparing PP-g-GMA-NMDG is both viable and environmentally benign. The PP-g-GMA-NMDG that was made has better qualities than other similar adsorbents. It has a high adsorption capacity, great selectivity, reliable repeatability, and easy recovery. These advantages indicated that the adsorbents have significant potential for widespread application in the separation of boron in water. [ABSTRACT FROM AUTHOR]

Most superhydrophobic surfaces contain fluorine, which is very harmful to the environment. So, it is necessary to change the situation. This paper explains that a simple and fluorine-free plasma technology for superhydrophobic modification of silk fabrics by using one-sided protection method and low-temperature plasma induced grafting polymerization of octamethyl-cyclotetrasiloxane (D4) to form the superhydrophobic films. Treated silk and pristine silk fabrics were measured using field emission scanning electron microscopy(FESEM), Fourier-transform infrared spectroscopy(FTIR), X-ray photoelectron spectroscopy(XPS), and water contact angle measurement. The test results showed that the polymer films could be successful coated on the silk fibers surface via the low-temperature plasma. In addition, it has good durability, thermal stability, and a water contact angle of 152°. [ABSTRACT FROM AUTHOR]

This study focused on the effects of alternating current (AC) and radio frequency (RF) power in the formation of plasma polymerized 3,4-ethylenedioxythiophene (PPEDOT) thin films onto glass substrates. Field emission scanning electron microscopy revealed that thin films produced both in AC and RF conditions exhibited a pristine surface morphology without any pinholes. Fourier transform infrared spectroscopy indicated that the chemical compositions of the PPEDOT films differed from that of the 3,4-ethylenedioxythiophene (EDOT) monomer due to structural rearrangements. The energy band gap values determined from the UV–Vis spectra were approximately 3.68 eV for the samples produced under AC power, while those for the samples produced under RF power were relatively higher, around 3.84 eV. Furthermore, the thin films synthesized using RF power and AC power exhibited significant differences in optical properties, including Urbach energy, extinction coefficient, steepness parameter, refractive index, optical conductivity, and skin depth. The EDOT monomer, PPEDOT and computed PEDOT via Density Functional Theory have been explicitly modeled with the intend to scrutinize the interplay between polymer formation and the modulation of molecular orbital energy levels, calculating band gaps, and molecular vibrations.

Surgical site infections (SSI) are major post‐operative complications following surgery. Reducing SSI is a global urgency as they account for huge pecuniary, physiological, and emotional burdens for patients. Antibiotic resistance is the main challenge for surgeons dealing with SSIs. Aggregation‐induced emission photosensitisers (AIE PS) with their distinct optical characteristics, biocompatibility, low toxicity, and target specificity, hold the potential for the treatment of SSI. Herein, a synergetic strategy combining plasma polymerization and AIE PS is adopted to develop coatings that can eradicate SSI‐causing bacteria. These coatings can preferentially kill Gram‐negative and Gram‐positive bacteria over mammalian cells after triggered by light irradiation. The cell viability and immunostaining studies confirmed their biocompatibility on mammalian cells. The antibacterial mechanistic studies explored their ability to generate reactive oxygen species (ROS), which is crucial for overcoming antibiotic resistance. Thus, this study opens an avenue toward antibacterial coatings to decrease the prevalence of SSI. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO)‐releasing coatings have promising potential for biomedical applications notably in implant safety and wound dressing by promoting healing and reducing bacterial growth. Yet, the production of NO‐films remains difficult through classic approaches. In this study, plasma polymerized NO‐coatings are produced using a helium‐isopentyl nitrite mixture under two power settings and deposited on aluminum samples. Analyses of the plasma phase by mass spectroscopy reveal the presence of nitrosoxy groups (O–N═O) in monomer and quasi‐monomer at low power, and a higher fragmentation rate at high power. Static and no‐static samples are made and analyzed by X‐ray photoelectron spectroscopy showing the presence of these group for both power conditions, with a better retention on the sample's center for the latest. [ABSTRACT FROM AUTHOR]

Atmospheric‐pressure plasma‐enhanced film deposition with single‐filament dielectric‐barrier discharges (DBDs) in argon was investigated using allyltrimethylsilane (ATMS) as a precursor. Nonionic deposition in the discharge zone is largely precluded by a rapid cross‐flow of the source gas, containing between 50 and 2000 ppm of ATMS. The performed experimental studies show a surprisingly large deposited film mass per transferred elementary charge between 220 and 540 amu. Film growth experiments, mass‐spectrometric studies, and kinetic considerations led to the conclusion that the deposition process is a cationic surface polymerization, initiated by ions produced in the DBD by energy transfer from long‐lived excited Ar species and propagated by addition of ATMS monomer molecules. [ABSTRACT FROM AUTHOR]

This study deals with removing crude oil droplets from colloidal oil in water emulsions. The target was the development of efficient adsorbents for the tertiary treatment of industrial-produced water (PW). The novel adsorbent was designed from recycled low-density polyethylene (LDPE) powder grafted by the cationic polymer. The cationic polymer was synthesized directly on the LDPE surface by plasma-induced radical polymerization. A positively charged adsorbent was chosen due to the negative character of oily droplets to enhance separation efficiency in treating oil-water emulsions. The separation was performed in both batch and filtration modes. Absorption/adsorption uptake capacities showed a sigmoidal S-shape that was analyzed using the Sips model and compared with the newly developed empirical model. Both models showed a remarkable coincidence in the description of experimental data. The separation efficiency of the novel adsorbent was also tested in a filtration mode mimicking a commonly used deep-bed filtration technology. The comparison of the separation efficiency for various sorbents indicated a supreme performance of novel adsorbent. This study demonstrates the potential of a relatively cheap, prepared commodity-based adsorbent for the purification of emulsified oily polluted water in both batch and filtration configurations. This study also contributes to the recycling of polyethylene waste because LDPE attracts meager interest in recycled LLDPE due to many obstacles to reusing LDPE waste for its reprocessing as packaging materials. [ABSTRACT FROM AUTHOR]

Plasma-surface modification method (PSMM) is an efficient and inexpensive surface processing method for various materials and has generated great interest in the field of biomedical engineering. This paper focuses on the numerous conventional plasma methods and experimental approaches applied to materials research for suitable biomedical applications, including plasma deposition, laser plasma deposition, plasma sputtering and etching, plasma polymerization, plasma spraying, plasma implantation, and so on. The distinctive benefit of plasma modification is its biocompatibility and surface properties can be enhanced on a selective basis while the bulk characteristics of the materials stay unaltered. Existing materials can hence be used and the requirement for new materials may be circumvented thereby reducing the time for the development of novel and efficient biomedical devices. [ABSTRACT FROM AUTHOR]

Organic thin films are of great interest due to their intriguing interfacial and functional properties, especially for device applications such as thin-film transistors and sensors. As their thickness approaches single nanometer thickness, characterization and interpretation of the extracted data become increasingly complex. In this study, plasma polymerization is used to construct ultrathin films that range in thickness from 1 to 20 nm, and time-of-flight secondary ion mass spectrometry coupled with principal component analysis is used to investigate the effects of film thickness on the resulting spectra. We demonstrate that for these cross-linked plasma polymers, at these thicknesses, the observed trends are different from those obtained from thicker films with lower degrees of cross-linking: contributions from ambient carbon contamination start to dominate the mass spectrum; cluster-induced nonlinear enhancement in secondary ion yield is no longer observed; extent of fragmentation is higher due to confinement of the primary ion energy; and the size of the primary ion source also affects fragmentation (e.g., Bi1 versus Bi5). These differences illustrate that care must be taken in choosing the correct primary ion source as well as in interpreting the data. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) nonwovens are used in many hygiene, healthcare and medical products due to their low cost, high chemical resistance and inertness. From an economic point of view, PP textiles would be used as an excellent support material in regenerative medicine or tissue engineering, but here surface functionalization is necessary to ensure cell adhesion and proliferation. Acrylic acid (AAc) is an excellent source of carboxylic-rich (-COOH) coatings suitable for this purpose, but their multistep preparation is time-consuming. Plasma polymerization provides an excellent solution to this demanding procedure since the process of polymerization and grafting to the substrate takes place simultaneously. Here, we propose a relatively fast and effective method for AAc plasma polymerization by using a pulsed underwater diaphragm electrical discharge operated in an aqueous solution consisting of AAc. AAc layers are successfully grafted onto PP nonwovens, which are continuously rewound through the slit where the plasma is generated. The presence of plasma polymerized AAc layer in the fibrous structure of PP nonwoven was monitored by SEM, FTIR and XPS measurements. Additionally, the improved wettability and adhesion characteristics were investigated by the critical wetting surface tension (CWST) method, the standard method of strike-through time (STT) and „tape-peel" test. Resulting AAc modified PP nonwoven possesses hydrophilic character, enhanced adhesion and a considerable amount of -COOH groups on the surface. Although after the washing test the FTIR and XPS results indicated a lower concentration of the carboxylic groups, the CWST and STT measurements confirmed the stable hydrophilic character of the PP nonwovens surface. [ABSTRACT FROM AUTHOR]

Hybrid thin films hold dominant importance in various technological applications due to their synergistic effects between inorganic and organic materials. In this study, inorganic–organic hybrid thin film has been produced where the inorganic layer of zinc selenide (ZnSe) is deposited first through chemical bath deposition technique and the organic layer is deposited onto the inorganic layer using a capacitively coupled plasma polymerization technique. The ZnSe layer deposited for one hour has been used as the base layer and plasma polymerized (PP) o-methoxyaniline (OMA) has been deposited for different deposition durations. The experimental results showed that thickness of the the hybrid films increases with the organic layer deposition time. The field emission scanning electron microscope exhibited a large number of pores on the surface of the ZnSe film, which are significantly covered up when organic PPOMA is deposited onto it. The energy-dispersive X-ray confirms the constitutional elements of the hybrid films and X-ray diffraction study indicates the enhancement of crystallinity of the film. Differential scanning calorimetry and thermogravimetric analysis specify that hybrid films are thermally more stable (up to 396 °C) compared to pure ZnSe film (351 °C), probably due to higher conjugation in the PP organic layer. The direct optical band gaps of the deposited hybrid thin films are found to increase from 2.4 to 2.80 eV with the increase of organic layer onto ZnSe film. Consequently, the Urbach energy decreases from 0.94 to 0.66 eV with the deposition of hybrid film for different time durations. The outcomes of this study suggest that the hybrid films would have enormous potential as passive thin films for photovoltaic cells, sensing and optical devices.

Beta-cyclodextrins (β-CDs) comprise a pore for accommodating resveratrol (Res), thereby boosting its bioavailability. Res-incorporated β -CD (Res/CD) may be cytotoxic against both normal and cancer cells. Herein, we examined whether Res/CD exhibits anticancer activity against tumor spheroids, similar to in vivo tumor mass. To prepare three-dimensional spheroids, 1,1,1,3,5,7,7,7 octamethyl-3,5-bis(trimethylsiloxyl) tetrasiloxane (OMBTSTS) was deposited to the surface of the culture dish via plasma polymerization. We observed that HeLa cells grew as spheroids on the OMBTSTS-deposited surface at 20 W plasma power. Res/CD was delivered to the hypoxic core of the spheroid, inducing necrosis, whereas Res was not. Consistently, 10 μM Res alone was not cytotoxic to two-dimensional HeLa cells grown on a culture dish and three-dimensional spheroids. However, Res/CD promoted the necroptosis of spheroids, which were split into small fragments, ultimately inducing cell spheroid death. Collectively, our data suggest that nontoxic levels of Res/CD were efficiently delivered to the hypoxic core of tumor spheroids, promoting cell death. Therefore, Res/CD can be used as an effective anticancer drug. Moreover, the plasma-polymerized OMBTSTS modification technique provides insights into the efficient formation of spheroids in various cancer cell lines. [ABSTRACT FROM AUTHOR]

The electrophysical parameters of the plasma and the kinetics of plasma-chemical processes in a CF4 + H2 + Ar mixture while varying the CF4/H2 ratio are studied. When using diagnostic methods and plasma modeling together, it is found that replacing tetrafluoromethane with hydrogen (a) leads to a decrease in the plasma density and an increase in electronegativity; and (b) it causes a disproportionately sharp drop in the concentration of fluorine atoms. The reason for the latter effect is the increase in the frequency of the death of atoms in reactions of the CHFx + F → CFx + HF type initiated by heterogeneous recombination via the CFx + H → CHFx mechanism. The simultaneous increase in the concentration of polymer-forming CHxFy (x + y < 3) radicals indicates an increase in the polymerization load of the plasma on the surfaces in contact with it. [ABSTRACT FROM AUTHOR]

This study aims to explore the plasma polymerization reaction of fluorocarbon gases, with specific focus on three monomers: tetrafluoromethane, hexafluoroethane, and octafluorocyclobutane. Optical emission spectroscopy was employed to observe species within the glow discharge, while detecting plasma species in fluorocarbon plasma polymerization. Fluorocarbon plasma polymerized films surface morphology and roughness were scrutinized using scanning electron microscopy and atomic force microscopy. Chemical bonding on film surfaces was probed using X-ray photoelectron spectroscopy. Experimental outcomes highlight the essential role of chemical interactions between fluorocarbon plasma and monomers, with film surface composition inferred from fluorocarbon ratio analysis. These analyses improve the understanding of fluorocarbon-to-carbon ratio and duty cycle contributions to plasma polymerized film growth, which promises advancements in the ability to tailor fluorocarbon films to specific applications. [ABSTRACT FROM AUTHOR]

Interfacial properties of nanomaterials and polymer matrix in nanocomposites strongly affect not only the dispersion of nanomaterials within the matrix, but also the mechanical properties and performance of nanocomposite. This work is aimed at providing a facile and single-step method for tailoring surface energy of cellulose nanocrystals (CNCs) to control the interfacial properties of polycaprolactone (PCL)/CNC nanocomposite. 1H,1H,2H,2H-perfluorodecyl acrylate (PFDA) monomers were polymerized on the surface of CNCs using low-pressure plasma polymerization. The success of polymerization process was verified by a variety of analytical techniques. As a direct consequence of dominance of polymerization or ablation processes, CNCs with various surface energies ranging between 8.0 and 42.4 mJ/m2 were successfully obtained by changing plasma power and duration in both continuous and pulse modes, and pulse-off time in pulse mode. The unmodified and modified CNCs with known surface energies were added to the PCL-based solution to make PCL/CNC nanocomposites with different interfacial properties through dry casting. Using DMTA and tensile measurement experiments, it was demonstrated that the compatibility of surface energies between two components of a nanocomposite, i.e., nanoparticle and matrix, is of paramount importance to enhance the dispersion of nanomaterials within the matrix as well as controlling the interfacial properties to reach the desired mechanical properties. Using modified CNCs with tailored surface energies, Tg, Young's modulus and tensile strength of the PCL/CNC nanocomposite were increased by approximately 13.4%, 23.6% and 14.8%, respectively, with respect to the neat PCL film. These values for unmodified CNCs were about 11.1%, 17.9% and 0%, respectively. [ABSTRACT FROM AUTHOR]

Bone marrow‐derived mesenchymal stromal cells (BMSCs) are extensively being utilized for cartilage regeneration owing to their excellent differentiation potential and availability. However, controlled differentiation of BMSCs towards cartilaginous phenotypes to heal full‐thickness cartilage defects remains challenging. This study investigates how different surface properties induced by either coating deposition or biomolecules immobilization onto nanofibers (NFs) could affect BMSCs chondro‐inductive behavior. Accordingly, electrospun poly(ε‐caprolactone) (PCL) NFs were exposed to two surface modification strategies based on medium‐pressure plasma technology. The first strategy is plasma polymerization, in which cyclopropylamine (CPA) or acrylic acid (AcAc) monomers were plasma polymerized to obtain amine‐ or carboxylic acid‐rich NFs, respectively. The second strategy uses a combination of CPA plasma polymerization and a post‐chemical technique to immobilize chondroitin sulfate (CS) onto the NFs. These modifications could affect surface roughness, hydrophilicity, and chemical composition while preserving the NFs' nano‐morphology. The results of long‐term BMSCs culture in both basic and chondrogenic media proved that the surface modifications modulated BMSCs chondrogenic differentiation. Indeed, the incorporation of polar groups by different modification strategies had a positive impact on the cell proliferation rate, production of the glycosaminoglycan matrix, and expression of extracellular matrix proteins (collagen I and collagen II). The chondro‐inductive behavior of the samples was highly dependent on the nature of the introduced polar functional groups. Among all samples, carboxylic acid‐rich NFs promoted chondrogenesis by higher expression of aggrecan, Sox9, and collagen II with downregulation of hypertrophic markers. Hence, this approach showed an intrinsic potential to have a non‐hypertrophic chondrogenic cell phenotype. [ABSTRACT FROM AUTHOR]

As a new trend in plasma surface engineering, plasma conditions that allow more-defined chemical reactions at the surface are being increasingly investigated. This is achieved by avoiding high energy deposition via ion bombardment during direct plasma exposure (DPE) causing destruction, densification, and a broad variety of chemical reactions. In this work, a novel approach is introduced by placing a polymer mesh with large open area close to the plasma–sheath boundary above the plasma-treated sample, thus enabling near-plasma chemistry (NPC). The mesh size effectively extracts ions, while reactive neutrals, electrons, and photons still reach the sample surface. The beneficial impact of this on the plasma activation of poly (tetrafluoroethylene) (PTFE) to enhance wettability and on the plasma polymerization of siloxanes, combined with the etching of residual hydrocarbons to obtain highly porous SiOx coatings at low temperatures, is discussed. Characterization of the treated samples indicates a predominant chemical modification yielding enhanced film structures and durability. [ABSTRACT FROM AUTHOR]

Covalent biofunctionalization of implant surfaces using anti microbial agents is a promising approach to reducing bone infection and implant failure. Radical‐rich, ion‐assisted plasma polymerized (IPP) coatings enable surface covalent biofunctionalization in a simple manner; but until now, they are limited to only 2D surfaces. Here a new technology is demonstrated to create homogenous IPP coatings on 3D materials using a rotating, conductive cage that is negatively biased while immersed in RF plasma. Evidence is provided that under controlled energetic ion bombardment, this technology enables the formation of highly robust and homogenous radical‐rich coatings on 3D objects for subsequent covalent attachment of antimicrobial agents. To functionally apply this technology, the broad‐spectrum antimicrobial CSA‐90 is attached to the surfaces, where it retained potent antibacterial activity against Staphylococcus aureus. CSA‐90 covalent functionalization of stainless‐steel pins used in a murine model of orthopedic infection revealed the highly promising potential of this coating system to reduce S. aureus infection‐related bone loss. This study takes the previous research on plasma‐based covalent functionalization of 2D surfaces a step further, with important implications for ushering in a new dimension in the biofunctionalization of 3D structures for applications in bone implants and beyond. [ABSTRACT FROM AUTHOR]

Development of ultrathin film (utf) hydrogels for cutting‐edge biomedical applications (i.e. artificial skins) is receiving increasing attention. Nonetheless, achieving accurate control on the structure and thickness of utf‐hydrogels becomes extremely complex when assessed through conventional techniques. In this work, an atmospheric‐pressure plasma‐assisted deposition technique is reported, showing great thickness accuracy and versatility, to design utf‐hydrogels with customized properties. For the first time, specific and independent control on the generation and nature of cross‐links by only changing the plasma exposure frequency (fPE) during the synthesis process are reported. Thus, utf‐hydrogels are successfully prepared with tuned swelling ratios and viscoelastic properties (ranging from 150 to 20 kPa). Moreover, a thickness accuracy of 9 nm is reported, permitting the accurate synthesis of utf‐hydrogels below 150 nm. Exhaustive structural and topographical analyses allow elucidating the effects of the fPE on the cross‐link generation mechanism, discarding any undesired effect on the thickness accuracy. To support the structural results obtained, quartz‐crystal microbalance with dissipation (QCM‐D) coupled with spectroscopic ellipsometry are put in the spotlight as an efficient and viable alternative for the characterization of the resulting properties of ultrathin film soft materials, including the presence of a hydrated layer at the interface. [ABSTRACT FROM AUTHOR]

Hydrophobic coatings have attracted much attention due to their wide applications in various industries including electronics, textiles, and automotive. This study deals with the process of creating nanoscale coatings on a substrate achieved by plasma polymerization using plasma flow (jet) using radiofrequency discharge together with the precursor c6h18osi2 and the carrier gas Ar. In this work, we investigate the production of hydrophobic coatings using radiofrequency (RF) discharge at atmospheric pressure using a mixture of argon (Ar) and hexamethyldisiloxane (HMDSO). RF discharge is a versatile and efficient method of plasma generation that allows the deposition of thin films with defined properties. Here we investigate the influence of process parameters such as gas flow rate, discharge power, and substrate temperature on the morphology, chemistry, and hydrophobicity of the deposited coatings. The formation of these coatings was carefully studied under atmospheric pressure conditions, varying the number of cycles of experiments while maintaining optimal plasma parameters. The properties and elemental composition of the coatings were thoroughly studied using scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS). In addition, the obtained coatings were found to possess hydrophobic properties. The hydrophobicity of these coatings was evaluated by measuring the contact angle with a goniometer with respect to cycles of experiments and long-term durability. This study contributes to a better understanding of the synthesis, structure, and hydrophobic characteristics of nanoscale coatings, opening promising perspectives for various applications. The results show that the hydrophobicity of the coatings can be optimized by tuning the process parameters, resulting in coatings with water contact angles greater than 160 degrees. Additionally, the durability and stability of the hydrophobic coatings are evaluated under different environmental conditions, allowing an assessment of their potential for practical applications. [ABSTRACT FROM AUTHOR]

Developing antibacterial materials is an efficient way to reduce the risk of harmful microorganism to human body. As a kind of popular textiles, cotton fabric (CF) is easy to breed microorganism and it is necessary to render it with biocidal effect. In this work, a water-soluble N-halamine precursor, (E)-1-(4-(allyloxy)phenyl)-N-(2-(piperazin-1-yl)ethyl)methanimine (APPEM), was synthesized and grafted onto cotton fabric through an argon plasma-induced grafting polymerization process. Afterward, the grafted cotton fabric was exposed to dilute sodium hypochlorite solution to change N–H bond into N–Cl bond and then the antibacterial cotton fabric (CF-APPEM-Cl) was obtained. The treated cotton fabric presented considerable biocidal efficacy and stability against UV light, washing, and storage. Escherichia coli (6.63 logs) and Staphylococcus aureus (6.44 logs) could be effectively inactivated within 60 min. Also, the oxidative chlorine on the fabric recovered over 76.9 and 81.5% after UV irradiation for 24 h and 50 washing cycles, respectively. And the oxidative chlorine remained 85% after 30 days of storage. Meanwhile, the mechanical properties of cotton fabric were hardly affected by this antibacterial treatment. This work provides a simple and efficient way to prepare antibacterial cotton fabric with high performance, which might be helpful to promote the development of antibacterial textiles. [ABSTRACT FROM AUTHOR]

Poly(2-oxazoline) is a promising new class of polymeric materials due to their antibiofouling properties and good biocompatibility. Poly(2-oxazoline) coatings can be deposited on different substrates via plasma polymerization, which can be more advantageous than other coating methods. The aim of this study is to deposit poly(2-oxazoline) coatings using a surface dielectric barrier discharge burning in nitrogen at atmospheric pressure using 2-methyl-2-oxazoline and 2-ethyl-2-oxazoline vapours as monomers and compare the film properties. For the comparison, the antibacterial and cytocompatibility tests were peformed according to ISO norms. The antibacterial tests showed that all the deposited films were highly active against Staphylococcus aureus and Escherichia coli bacteria. The chemical composition of the films was studied using FTIR and XPS, and the film surface's properties were studied using AFM and surface energy measurement. The cytocompatibility tests showed good cytocompatibility of all the deposited films. However, the films deposited from 2-methyl-2-oxazoline exhibit better cytocompatibility. This difference can be explained by the different chemical compositions and surface morphologies of the films deposited from different monomers. [ABSTRACT FROM AUTHOR]