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1.
Food Chem ; 464(Pt 1): 141571, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39426267

RESUMO

Plasma polymerization at atmospheric pressure provides an eco-friendly alternative to wet chemistry for creating antibacterial coatings for food packaging. However, the degradation of these coatings in contact with food remains underexplored. This study employs an aerosol-assisted atmospheric plasma system to deposit polyethylene glycol (PEG)-like coatings with 1 wt% zinc oxide (ZnO) nanoparticles on a polymer substrate. Fourteen degradation products, differ mainly in the number of ethylene oxide groups were identified in food simulants, with the highest releases associated with C6H14O4 and C10H22O5. Increasing plasma input power from 200 to 350 W enhanced crosslinking and increased ZnO nanoparticle content from 1.6 ± 0.3 to 5.9 ± 0.8 at. %, resulting in lower release of the degradation products. Toxicity evaluations, including Daphnia magna LC50 (48 h) and oral rat LD50 tests, confirmed the non-toxic nature of these substances. These findings suggest that plasma-polymerized coatings are safe and effective for antibacterial food packaging.

2.
ACS Appl Mater Interfaces ; 16(38): 50507-50523, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39263871

RESUMO

Immunoglobulin G (IgG) comprises a significant portion of the protein corona that forms on biomaterial surfaces and holds a pivotal role in modulating host immune responses. To shed light on the important relationship between biomaterial surface functionality, IgG adsorption, and innate immune responses, we prepared, using plasma deposition, four surface coatings with specific chemistries, wettability, and charge. We found that nitrogen-containing coatings such as these deposited from allylamine (AM) and 2-methyl-2-oxazoline (POX) cause the greatest IgG unfolding, while hydrophilic acrylic acid (AC) surfaces allowed for the retention of the protein structure. Structural changes in IgG significantly modulated macrophage attachment, migration, polarization, and the expression of pro- and anti-inflammatory cytokines. Unfolded IgG on the POX and AM surfaces enhanced macrophage attachment, migration, extracellular trap release, and pro-inflammatory factors production such as IL-6 and TNF-α. Retention of IgG structure on the AC surface downregulated inflammatory responses. The findings of this study demonstrate that the retention of protein structure is an essential factor that must be taken into consideration when designing biomaterial surfaces. Our study indicates that using hydrophilic surface coatings could be a promising strategy for designing immune-modulatory biomaterials for clinical applications.


Assuntos
Imunoglobulina G , Propriedades de Superfície , Imunoglobulina G/química , Imunoglobulina G/imunologia , Camundongos , Animais , Desdobramento de Proteína , Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Humanos , Células RAW 264.7 , Interações Hidrofóbicas e Hidrofílicas , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Adsorção , Citocinas/metabolismo , Citocinas/imunologia
3.
ACS Biomater Sci Eng ; 10(10): 6230-6240, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39213601

RESUMO

The adsorption of serum proteins on biomaterial surfaces is a critical determinant for the outcome of medical procedures and therapies, which involve inserting materials and devices into the body. In this study, we aimed to understand how surface topography at the nanoscale influences the composition of the protein corona that forms on the (bio)material surface when placed in contact with serum proteins. To achieve that, we developed nanoengineered model surfaces with finely tuned topography of 16, 40, and 70 nm, overcoated with methyl oxazoline to ensure uniform outermost chemistry across all surfaces. Our findings revealed that within the studied height range, surface nanotopography had no major influence on the overall quantity of adsorbed proteins. However, significant alterations were observed in the composition of the adsorbed protein corona. For instance, clusterin adsorption decreased on all the nanotopography-modified surfaces. Conversely, there was a notable increase in the adsorption of ApoB and IgG gamma on the 70 nm nanotopography. In comparison, the adsorption of albumin was greater on surfaces that had a topography scale of 40 nm. Analysis of the gene enrichment data revealed a reduction in protein adsorption across all immune response-related biological pathways on nanotopography-modified surfaces. This reduction became more pronounced for larger surface nanoprotrusions. Macrophages were used as representative immune cells to assess the influence of the protein corona composition on inflammatory outcomes. Gene expression analysis demonstrated reduced inflammatory responses on the nanotopographically modified surface, a trend further corroborated by cytokine analysis. These findings underscore the potential of precisely engineered nanotopography-coated surfaces for augmenting biomaterial functionality.


Assuntos
Materiais Biocompatíveis , Proteínas Sanguíneas , Propriedades de Superfície , Adsorção , Proteínas Sanguíneas/química , Proteínas Sanguíneas/metabolismo , Materiais Biocompatíveis/química , Humanos , Coroa de Proteína/química , Coroa de Proteína/metabolismo , Animais , Camundongos , Nanotecnologia
4.
Polymers (Basel) ; 16(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38891493

RESUMO

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).

5.
Adv Mater ; 36(31): e2403114, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38781555

RESUMO

Multi-responsive nanomembranes are a new class of advanced materials that can be harnessed in complex architectures for micro and nano-manipulators, artificial muscles, energy harvesting, soft robotics, and sensors. The design and fabrication of responsive membranes must meet such challenges as trade-offs between responsiveness and mechanical durability, volumetric low-cost production ensuring low environmental impact, and compatibility with standard technologies or biological systems This work demonstrates the fabrication of multi-responsive, mechanically robust poly(1,3-diaminopropane) (pDAP) nanomembranes and their application in fast photoactuators. The pDAP films are developed using a plasma-assisted polymerization technique that offers large-scale production and versatility of potential industrial relevance. The pDAP layers exhibit high elasticity with the Young's modulus of ≈7 GPa and remarkable mechanical durability across 20-80 °C temperatures. Notably, pDAP membranes reveal immediate and reversible contraction triggered by light, rising temperature, or reducing relative humidity underpinned by a reversible water sorption mechanism. These features enable the fabrication of photoactuators composed of pDAP-coated Si nanocantilevers, demonstrating ms timescale response to light, tens of µm deflections, and robust performance up to kHz frequencies. These results advance fundamental research on multi-responsive nanomembranes and hold the potential to boost versatile applications in light-to-motion conversion and sensing toward the industrial level.

6.
Small ; 20(31): e2311204, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38459801

RESUMO

Constructing a flexible and chemically stable multifunctional layer for the lithium (Li) metal anodes is a highly effective approach to improve the uneven deposition of Li+ and suppress the dendrite growth. Herein, an organic protecting layer of polythiophene is in situ polymerized on the Li metal via plasma polymerization. Compared with the chemically polymerized thiophene (C-PTh), the plasma polymerized thiophene layer (P-PTh), with a higher Young's modulus of 8.1 GPa, shows strong structural stability due to the chemical binding of the polythiophene and Li. Moreover, the nucleophilic C─S bond of polythiophene facilitates the decomposition of Li salts in the electrolytes, promoting the formation of LiF-rich solid electrolyte interface (SEI) layers. The synergetic effect of the rigid LiF as well as the flexible PTh-Li can effectively regulate the uniform Li deposition and suppress the growth of Li dendrites during the repeated stripping-plating, enabling the Li anodes with long-cycling lifespan over 8000 h (1 mA cm-2, 1 mAh cm-2) and 2500 h (10 mA cm-2, 10 mAh cm-2). Since the plasma polymerization is facile (5-20 min) and environmentally friendly (solvent-free), this work offers a novel and promising strategy for the construction of the forthcoming generation of high-energy-density batteries.

7.
Nanomaterials (Basel) ; 14(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38251159

RESUMO

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.

8.
J Biomed Mater Res A ; 112(2): 210-230, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37706337

RESUMO

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.


Assuntos
Células-Tronco Mesenquimais , Nanofibras , Humanos , Condrogênese , Diferenciação Celular , Colágeno/química , Ácidos Carboxílicos , Células Cultivadas
9.
Nanomaterials (Basel) ; 13(20)2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37887925

RESUMO

Currently, there is considerable interest in seeking an environmentally friendly technique that is neither thermally nor organic solvent-dependent for producing advanced polymer films for food-packaging applications. Among different approaches, plasma polymerization is a promising method that can deposit biodegradable coatings on top of polymer films. In this study, an atmospheric-pressure aerosol-assisted plasma deposition method was employed to develop a poly(ethylene glycol) (PEG)-like coating, which can act as a potential matrix for antimicrobial agents, by envisioning controlled-release food-packaging applications. Different plasma operating parameters, including the input power, monomer flow rate, and gap between the edge of the plasma head and substrate, were optimized to produce a PEG-like coating with a desirable water stability level and that can be biodegradable. The findings revealed that increased distance between the plasma head and substrate intensified gas-phase nucleation and diluted the active plasma species, which in turn led to the formation of a non-conformal rough coating. Conversely, at short plasma-substrate distances, smooth conformal coatings were obtained. Furthermore, at low input powers (<250 W), the chemical structure of the precursor was mostly preserved with a high retention of C-O functional groups due to limited monomer fragmentation. At the same time, these coatings exhibit low stability in water, which could be attributed to their low cross-linking degree. Increasing the power to 350 W resulted in the loss of the PEG-like chemical structure, which is due to the enhanced monomer fragmentation at high power. Nevertheless, owing to the enhanced cross-linking degree, these coatings were more stable in water. Finally, it could be concluded that a moderate input power (250-300 W) should be applied to obtain an acceptable tradeoff between the coating stability and PEG resemblance.

10.
Polymers (Basel) ; 15(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37688233

RESUMO

This comprehensive review begins by tracing the historical development and progress of cold plasma technology as an innovative approach to polymer engineering. The study emphasizes the versatility of cold plasma derived from a variety of sources including low-pressure glow discharges (e.g., radiofrequency capacitively coupled plasmas) and atmospheric pressure plasmas (e.g., dielectric barrier devices, piezoelectric plasmas). It critically examines key operational parameters such as reduced electric field, pressure, discharge type, gas type and flow rate, substrate temperature, gap, and how these variables affect the properties of the synthesized or modified polymers. This review also discusses the application of cold plasma in polymer surface modification, underscoring how changes in surface properties (e.g., wettability, adhesion, biocompatibility) can be achieved by controlling various surface processes (etching, roughening, crosslinking, functionalization, crystallinity). A detailed examination of Plasma-Enhanced Chemical Vapor Deposition (PECVD) reveals its efficacy in producing thin polymeric films from an array of precursors. Yasuda's models, Rapid Step-Growth Polymerization (RSGP) and Competitive Ablation Polymerization (CAP), are explained as fundamental mechanisms underpinning plasma-assisted deposition and polymerization processes. Then, the wide array of applications of cold plasma technology is explored, from the biomedical field, where it is used in creating smart drug delivery systems and biodegradable polymer implants, to its role in enhancing the performance of membrane-based filtration systems crucial for water purification, gas separation, and energy production. It investigates the potential for improving the properties of bioplastics and the exciting prospects for developing self-healing materials using this technology.

11.
Front Bioeng Biotechnol ; 11: 1213021, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37675407

RESUMO

Introduction: Stem cell therapies have been investigated as potential treatment modalities for chronic wounds however there has been limited success to date. Multipotent Adult Progenitor Cells (MAPCs©) have been identified as having potential as an allogenic stem cell product due to their high population doubling number and their characteristic dampening of T-cell proliferation. This helps to prevent autoimmunity and graft/cell rejection. Methods: We have developed a dressing, consisting of medical grade silicone coated with a heptylamine plasma polymer, which supports the growth and transfer of MAPCs to skin. To determine if the dressing can deliver functional stem cells into diabetic wounds, they were loaded with MAPCs and then placed over excisional wounds in both normal and diabetic mice. Results and discussion: Accelerated healing was observed in both the normal and diabetic wounds with wound gape being significantly smaller at day 3 when compared to controls. Wound analysis showed that treatment with the MAPC dressings dampened the inflammatory response with reduced numbers of neutrophils and macrophages observed. Additionally, an increase in pro-angiogenic VEGF and CD31 positive endothelial cells was observed indicating improved new blood vessel formation. The MAPC dressings had no effect on fibrosis with collagen I and III being equally affected in both control and treated wounds. Overall, the functionalized MAPC dressings improve healing responses particularly in diabetic mice with impaired healing responses and therefore, show potential for development as an advanced therapeutic approach for the treatment of chronic diabetic wounds.

12.
J Funct Biomater ; 14(7)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37504830

RESUMO

The objective of this research was to develop an environment-friendly and scalable method for the production of self-sanitizing electrospun nanofibers. This was achieved by immobilizing silver nanoparticles (Ag NPs) onto plasma-treated surfaces of biodegradable polycaprolactone (PCL) nanofibers. The plasma deposited polymer layer containing carboxyl groups played a critical role in providing a uniform distribution of Ag NPs on the nanofiber surface. Ag ions were absorbed by electrostatic interaction and then reduced under the action of UV-light. The concentration and release of Ag ions were analyzed using the EDXS/XPS and ICP AES methods, respectively. Although high levels of Ag ions were detected after 3 h of immersion in water, the material retained a sufficient amount of silver nanoparticles on the surface (~2.3 vs. 3.5 at.% as determined by XPS), and the release rate subsequently decreased over the next 69 h. The antipathogenic properties of PCL-Ag were tested against gram-negative and gram-positive bacteria, fungi, and biofilm formation. The results showed that the PCL-Ag nanofibers exhibit significant antimicrobial activity against a wide range of microorganisms, including those that cause human infections. The incorporation of Ag NPs into PCL nanofibers resulted in a self-sanitizing material that can be used in variety of applications, including wound dressings, water treatment, and air filtration. The development of a simple, scalable, and environmentally friendly method for the fabrication of these nanofibers is essential to ensure their widespread use in various industries. The ability to control the concentration and release rate of Ag ions in the PCL nanofibers will be critical to optimize their efficacy while minimizing their potential toxicity to human cells and the environment.

13.
Polymers (Basel) ; 15(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37050242

RESUMO

Polyaniline (PANI) was synthesized from liquid aniline, a nitrogen-containing aromatic compound, through the atmospheric pressure (AP) plasma process using a newly designed plasma jet array with wide spacing between plasma jets. To expand the area of the polymerized film, the newly proposed plasma jet array comprises three AP plasma jet devices spaced 7 mm apart in a triangular configuration and an electrodeless quartz tube capable of applying auxiliary gas in the center of the triangular plasma jets. The vaporized aniline monomer was synthesized into a PANI film using the proposed plasma array device. The effects of nitrogen gas addition on the morphological, chemical, and electrical properties of PANI films in AP argon plasma polymerization were examined. The iodine-doped PANI film was isolated from the atmosphere through encapsulation. The constant electrical resistance of the PANI film indicates that the conductive PANI film can achieve the desired resistance by controlling the atmospheric exposure time through encapsulation.

14.
Biofouling ; 39(1): 47-63, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36856008

RESUMO

This study aimed to characterize the immobilization of the novel JIChis-2 peptide on the Ti-6Al-4V alloy, widely used in the biomedical sector. The antimicrobial activity of JIChis-2 was evaluated in the Gram-negative bacterium E. coli. Its immobilization occurred by inducing the formation of covalent bonds between the N-terminus of the peptides and the surface previously submitted to acrylic acid polymerization via the PECVD technique. Coated and uncoated surfaces were characterized by FTIR, AFM, SEM and EDX. Studies of global and localized corrosion were carried out, seeking to explore the effects triggered by surface treatment in an aggressive environment. Additionally, the ability of the functionalized material to prevent E. coli biofilm formation evidenced that the strategy to immobilize JIChis-2 in the Ti-6Al-4V alloy via PECVD of acrylic acid resulted in the development of a functional material with antibiofilm properties.


Assuntos
Peptídeos Antimicrobianos , Escherichia coli , Teste de Materiais , Polimerização , Biofilmes , Titânio/farmacologia , Titânio/química , Ligas/farmacologia , Ligas/química
15.
Gels ; 9(3)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36975686

RESUMO

Amphiphilic hydrogels from mixtures of 2-hydroxyethyl methacrylate and 2-(diethylamino)ethyl methacrylate p(HEMA-co-DEAEMA) with specific pH sensitivity and hydrophilic/hydrophobic structures were designed and polymerized via plasma polymerization. The behavior of plasma-polymerized (pp) hydrogels containing different ratios of pH-sensitive DEAEMA segments was investigated concerning possible applications in bioanalytics. In this regard, the morphological changes, permeability, and stability of the hydrogels immersed in solutions of different pHs were studied. The physico-chemical properties of the pp hydrogel coatings were analyzed using X-ray photoelectron spectroscopy, surface free energy measurements, and atomic force microscopy. Wettability measurements showed an increased hydrophilicity of the pp hydrogels when stored in acidic buffers and a slightly hydrophobic behavior after immersion in alkaline solutions, indicating a pH-dependent behavior. Furthermore, the pp (p(HEMA-co-DEAEMA) (ppHD) hydrogels were deposited on gold electrodes and studied electrochemically to investigate the pH sensitivity of the hydrogels. The hydrogel coatings with a higher ratio of DEAEMA segments showed excellent pH responsiveness at the studied pHs (pH 4, 7, and 10), demonstrating the importance of the DEAEMA ratio in the functionality of pp hydrogel films. Due to their stability and pH-responsive properties, pp (p(HEMA-co-DEAEMA) hydrogels are conceivable candidates for functional and immobilization layers for biosensors.

16.
Int J Mol Sci ; 24(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36614239

RESUMO

Fundamental knowledge about cell-surface interactions can be applied in the development of wound dressings and scaffolds to encourage wounds to heal. As surfaces produced with acid-functionalised monomers encourage keratinocyte adhesion, proliferation and migration, whilst amine functionalisation enhances fibroblast proliferation and migration in vitro, standard care wound dressings were plasma-coated with either acrylic acid or allylamine and applied to 6 mm excisional wounds on the backs of mice to test their effectiveness in vivo. At day 3, the rate of wound healing was increased in mice treated with dressings that were plasma-coated with allylamine compared to uncoated dressings, with a significantly reduced wound area. However, healing may be impaired following prolonged treatment with allylamine-functionalised dressings, with delayed re-epithelialisation and increased cellularisation of the wound site at later timepoints. Acrylic acid functionalisation, however, offered no early improvement in wound healing, but wounds treated with these dressings displayed increased collagen deposition at day 7 post wounding. These results suggest that plasma polymerisation may allow for the development of new dressings which can enhance wound closure by directing cell behaviour, but that the application of these dressings may require a timed approach to enhance specific phases of the wound healing response.


Assuntos
Bandagens , Cicatrização , Camundongos , Animais , Acrilatos/farmacologia , Colágeno
17.
Int J Food Microbiol ; 386: 110017, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36435098

RESUMO

The present study evaluates the anti-biofilm activity of a coating applied with an atmospheric-pressure plasma jet system on AISI 316 stainless steel (SS) against multispecies biofilms containing Listeria monocytogenes (using background microbiota from three different meat industries) using culture-dependent and culture-independent approaches. Also, the disinfection effectiveness and biofilm evolution after sanitization with two food industry biocides were assessed. The anti-biofilm activity of the coating against L. monocytogenes, observed on mono-species biofilms (p < 0.05), was lost on the multispecies biofilms developed for 7 days at 12 °C (p > 0.05), with L. monocytogenes counts ranging from 5.5 ± 0.7 to 6.1 ± 0.5 CFU/cm2 on the uncoated SS and from 4.4 ± 0.2 to 6.4 ± 0.5 CFU/cm2 on the coated SS. The taxonomic composition of the formed biofilms was highly dependent on the industry but not affected by the artificial inoculation with L. monocytogenes and the nature of the surface (coated vs uncoated SS). When L. monocytogenes was artificially inoculated, its growth was partially controlled in the biofilms developed, with the magnitude of this effect being lower (p < 0.05 on coated SS) for the industry with the lowest taxonomy richness and diversity (3.8 ± 0.2 CFU/cm2), as compared the other two sampled industries (2.4 ± 0.4 and 1.6 ± 0.2 CFU/cm2). The 15-min disinfection treatments with either sodium hypochlorite or peracetic acid at 0.5 % resulted in total viable and L. monocytogenes counts below the limit of detection in most cases, immediately after treatment. The subsequent incubation of the sanitized plates for another 7 days at 12 °C in fresh BHI media led to the development of biofilms with lower bacterial richness and alpha diversity, and higher beta diversity. Even though sodium hypochlorite was in general slightly less effective than peracetic acid immediately after application, it caused a stronger growth control (p < 0.05) of the naturally present L. monocytogenes on the multispecies biofilms developed. This finding highlights the importance of understanding the interspecific competitive relationships between the members of the background microbiota and L. monocytogenes for the long-term control of this pathogen in food processing facilities.


Assuntos
Listeria monocytogenes , Microbiota , Ácido Peracético/farmacologia , Aço Inoxidável/análise , Hipoclorito de Sódio , Biofilmes , Contagem de Colônia Microbiana , Microbiologia de Alimentos
18.
Trends Biotechnol ; 41(1): 63-76, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35863949

RESUMO

Antibacterial coatings are regarded as a necessary tool to prevent implant-related infections. Substrate-independent and widely applicable coating techniques are gaining significant interest to synthesize different types of antibacterial films, which can be relevant from a fundamental and application-oriented perspective. Plasma polymer- and polydopamine-based antibacterial coatings represent the most widely studied and versatile approaches among these coating techniques. Both single- and dual-functional antibacterial coatings can be fabricated with these approaches and a variety of dual-functional antibacterial coating strategies can still be explored in future work. These coatings can potentially be used for a wide range of different implants (material, shape, and size). However, for most implants, significantly more fundamental knowledge needs to be gained before these coatings can find real-life use.


Assuntos
Antibacterianos , Materiais Revestidos Biocompatíveis , Antibacterianos/farmacologia , Próteses e Implantes
19.
Materials (Basel) ; 15(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36500046

RESUMO

Hydrophobic and oleophilic Si-based cotton fabrics have recently gained a lot of attention in oil/water separation due to their high efficiency. In this study, we present the effect of O2 plasma pre-treatment on the final properties of two Si-based cotton membranes obtained from dip coating and plasma polymerization, using polydimethylsiloxane (PDMS) as starting polymeric precursor. The structural characterizations indicate the presence of Si bond on both the modified cotton surfaces, with an increase of the carbon bond, assuring the success in surface modification. On the other hand, employing O2 plasma strongly changes the cotton morphology, inducing specific roughness and affecting the hydrophobicity durability and separation efficiency. In particular, the wettability has been retained after 20 laundry tests at 40 °C and 80 °C, and, for separation efficiency, even after 30 cycles, an improvement in the range of 10-15%, both at room temperature and at 90 °C can be observed. These results clearly demonstrate that O2 plasma pre-treatment, an eco-friendly, non-toxic, solvent-free, and one-step method for inducing specific functionalities on surfaces, is very effective in enhancing the oil/water separation properties for Si-based cotton membranes, especially in combination with plasma polymerization procedure for Si-based deposition.

20.
Polymers (Basel) ; 14(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36559729

RESUMO

The spread of bacterial, fungal, and viral diseases by airborne aerosol flows poses a serious threat to human health, so the development of highly effective antibacterial, antifungal and antiviral filters to protect the respiratory system is in great demand. In this study, we developed ZnO-modified polycaprolactone nanofibers (PCL-ZnO) by treating the nanofiber surface with plasma in a gaseous mixture of Ar/CO2/C2H4 followed by the deposition of ZnO nanoparticles (NPs). The structure and chemical composition of the composite fibers were characterized by SEM, TEM, EDX, FTIR, and XPS methods. We demonstrated high material stability. The mats were tested against Gram-positive and Gram-negative pathogenic bacteria and pathogenic fungi and demonstrated high antibacterial and antifungal activity.

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