Antibacterial activity of graphene-based materials Szunerits, Sabine; Boukherroub, Rabah
Journal of materials chemistry. B, Materials for biology and medicine,
11/2016, Letnik:
4, Številka:
43
Journal Article
Recenzirano
Odprti dostop
Complications related to infectious diseases have significantly decreased due to the availability and use of a wide variety of antibiotics and antimicrobial agents. However, excessive use of ...antibiotics and antimicrobial agents over years has increased the number of drug resistant pathogens. Microbial multidrug resistance poses serious risks and consequently research attention has refocused on finding alternatives for antimicrobial treatment. Among the various approaches, the use of engineered nanostructures is currently the most promising strategy to overcome microbial drug resistance by improving the remedial efficiency due to their high surface-to-volume ratio and their intrinsic or chemically incorporated antibacterial activity. Graphene, a two-dimensional ultra-thin nanomaterial, possesses excellent biocompatibility, putting it in the forefront for different applications in biosensing, drug delivery, biomedical device development, diagnostics and therapeutics. Graphene-based nanostructures also hold great promise for combating microbial infections. Yet, several questions remain unanswered such as the mechanism of action with the microbial entities, the importance of size and chemical composition in the inhibition of bacterial proliferation and adhesion, cytotoxicity, and other issues when considering future clinical implementation. This review summarizes the current efforts in the formulation of graphene-based nanocomposites with antimicrobial and antibiofilm activities as new tools to tackle the current challenges in fighting against bacterial targets. Furthermore, the review describes the features of graphene-bacterial interactions, with the hope to shed light on the range of possible mode of actions, serving the goal to develop a better understanding of the antibacterial capabilities of graphene-based nanostructures.
Current efforts in the formulation of graphene-based nanocomposites with antimicrobial and antibiofilm activities in fighting against bacterial targets are reviewed.
Skin is susceptible to varying degrees of injury from external forces, heat, disease, and chemical corrosion. Wound dressings using tissue engineering principles can accelerate skin tissue repair, ...relieve patient pain, and reduce the formation of scars. In this study, the self-adhesive and self-healing hydrogel dressings based on quaternary ammonium chitosan (QCS), β-cyclodextrin-modified silk fibroin (CD-SF), and adamantane-modified silk fibroin (AD-SF), that was designed. The formed hydrogels not only based on the host-guest interactions between CD-SF as host polymer and AD-SF as guest polymer, also the hydrogen-bonding assembly from QCS was combined. The successful synthesis of QCS, CD-SF, and AD-SF was established using Fourier Transform Infrared spectroscopy (FT-IR) and 1H nuclear magnetic resonance (1H NMR) spectroscopy. The obtained QCS/CD-SF/AD-SF (QCA) hydrogels displayed self-adhesive, self-healing, and mechanical properties. The hydrogels exhibited antibacterial performance, combating typical Gram-negative bacteria Escherichia coli (E. coli) and Gram-positive bacteria Staphylococcus aureus (S. aureus). Further, CCK-8 assay by incubating hydrogels with NIH-3T3 cells and optical microscope inspection of cell morphology indicates the excellent cytocompatibility of the hydrogels. The designed QCA hydrogel with antibacterial properties and biocompatibility have great potential as wound dressings for wound healing treatment.
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The physicochemical, thermal and mechanical properties of blood orange peel pectin (BOPP) film blended with fish gelatin (F-G), at different ratios, were investigated. BOPP was first, tested for its ...antioxidant capacity, monitored through the β-carotene bleaching, DPPH radical-scavenging and reducing power activities. BOPP and gelatin blending was found to reduce the wettability of the gelatin film, whereas it slightly reduced its transparency. F-G:BOPP film prepared with equal ratios (50:50) showed the highest glass transition temperature (Tg ~ 79 °C) and tensile strength (TS ~ 14 MPa). The structure analysis of the blend films showed their homogeneity and miscibility, as revealed by the infrared spectra, the differential scanning calorimetry and the microstructure results. Of particular interest, blend films showed high antioxidant and antibacterial capacities, compared to the gelatin-based film and the best results were recorded in the F-G:BOPP (50:50) among all the other films, reaching 0.96, 50.36% and 67.36% for the reducing power, the β-carotene bleaching inhibition and the radical scavenging activity, respectively. Furthermore, the prepared films were used to wrap cheese in order to enhance their preservation. The results showed that the F-G:BOOP wrapping improved the physicochemical and the textural properties and the microbial stability of cheese during chilled storage. Thus, overall results encourage the further use of pectin-gelatin films as active packaging material.
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•Blend films based on blood orange peel pectin (BOPP) and gelatin were prepared.•BOPP addition resulted in more resistant films.•Wrapping of cheese by F-G:BOPP films improve its preservation.•F-G BOPP composite films can serve as active packaging material.
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•PES-g-IL NFMs were fabricated by combining radiation grafting with electrospinning;•The NFMs exhibit multifunctional properties, including dye and heavy metal absorption and ...antibacterial properties;•The NFMs can be easily regenerated with high absorption and desorption efficiency.
In view of the harmfulness of the pollutants in wastewater to both human being and environment, it is urgent to develop a multifunctional polymer adsorbent that can remove dyes, heavy metals and bacteria simultaneously. Herein, ionic liquid (IL) grafted Polyethersulfone (PES) (PES-g-IL) nanofibrous membranes (NFMs) were prepared by combining radiation induced grafting method and electrospinning strategy. The adsorption behavior, antibacterial property as well as reusability were examined for the obtained NFMs. It was found that the PES-g-IL NFMs exhibited excellent adsorption ability for heavy metal ions and dyes as well as good recyclability. The adsorption capacity for anionic dyes Congo Red (CR) and heavy metal ions (Cd(II)) reached 120.3 and 187.3 mg/g, respectively. The adsorption mechanism of CR was proved to be the electrostatic interaction between the NFMs and CR, while the adsorption of Cd(II) was driven by the complex between the nitrogen atoms on the imidazolium ring of the grafted ionic liquid and Cd(II). According to the adsorption kinetics, the adsorption of CR and Cd(II) was well fitted by the pseudo-second-order kinetic equation, indicating that the adsorption process was controlled by multiple steps. By calculating the thermodynamic parameters, it is indicated that the adsorption of CR and Cd(II) was a spontaneous physical adsorption process. In addition, PES-g-IL NFMs had excellent antibacterial ability. The killing rate of E. coli. was close to 99%. Given the above advantages, the PES-g-IL NFMs showed great potential in wastewater treatment.
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•A simple and efficient strategy was developed to synthesize bio-based dynamic covalent thermosets with Schiff bases and multiple hydrogen bonds from levulinic acid.•The obtained ...resin exhibited excellent thermal and mechanical properties with Tg up to 165 °C and tensile modulus up to 2422 MPa.•The resin illustrated rapid reprocessing and repairing without catalyst.•The resin showed intrinsic flame retardancy with LOI of 33.8 % and UL-94 V-0 rating.•The resin also exhibited 100% antibacterial activity against Escherichia coli and Staphylococcus aureus.
Bio-based dynamic covalent thermosets have attracted extensive attention as they are expected to break conventional thermosets' reliance on fossil resources and address the recycling issue after disposal. However, there has always been a contradiction between using bio-based feedstocks and possessing high properties, as well as a conflict between high performance and rapid recycling (reprocessing and degradation). In this work, a simple approach was developed to prepare bio-based thermosets with high performance, rapid reprocessing, high flame retardancy, and antibacterial properties enabled by in-situ generated dynamic covalent imine (Schiff base) bonds and multiple hydrogen bonds. The levulinic acid epoxy (ELA) was successfully synthesized and cured with 2-(4-aminophenyl)-1H-benzimidazol-5-amine (BIA) containing benzimidazole structures. The high concentration of Schiff bases and multiple hydrogen bonds of ELA-BIA endowed it with high glass transition temperature and mechanical properties, as well as satisfactory catalyst-free malleability, rapid reprocessing and repairing. Furthermore, due to the combined effect of the in-situ Schiff base and benzimidazole structure, ELA-BIA exhibited excellent condensed phase char formation ability, resulting in intrinsic flame retardancy with a limiting oxygen index of 33.8 % and a UL-94 V-0 rating, both of which were significantly higher than 4, 4′-diaminodiphenyl methane (DDM) cured ELA or DDM cured bisphenol A epoxy. Moreover, the Schiff bases bonded in the networks provided 100 % of the intrinsic antibacterial rates. This work provides a feasible and simple strategy for the preparation of high-performance and versatile bio-based dynamic covalent thermosets.
Carbon dots (CDs) with high quantum yield (QY), low toxicity and good biocompatibility are the major quests of biomedical research. In this paper, we develop a green, simple hydrothermal approach to ...synthesize water-soluble, nontoxic, highly photoluminescent carbon nanodots (CNDs) from Metronidazole, which possess selective antibacterial activity against obligate anaerobes for the first time. Metronidazole was used as a sole precursor to prepare CNDs at 250 °C (CNDs-250) for 8 h. After the CNDs-250 with an average size of 2.9 nm, consisting of a highly carbon crystalline core and various surface groups were obtained, the formation and fluorescence mechanisms of CNDs were further explored by adjusting the reaction time and reaction temperatures, respectively. Biological experimental data proved that CNDs-250 can only inhibit the growth of obligate anaerobes, such as Porphyromonas gingivalis (P. gingivalis) directly, instead of further functionalization. Besides, CNDs-250 with a QY around 28.1% exhibit an obvious excitation-dependent emission, which will be conducive to multicolor bioimaging. And it may not only develop a new approach for researchers to prepare multifunctional CDs, but also provide a valuable strategy for the theranostics of some diseases as well as other fields.
TiO2 based powders containing B2O3 and Nb2O5 were obtained through an aqueous sol-gel method. The as prepared gels were step wisely heated in the temperature range 200°C - 500°C and subsequently ...characterized by XRD, IR and UV-Vis analysis. The TiO2 (anatase) is the single crystalline phase which has been detected up to 500°C. Photocatalytic tests showed that the investigated samples possess photocatalytic activity toward Malachite green organic dye and TiO2/Nb2O5 exhibited higher photocatalytic activity than TiO2/B2O3 sample. The compositions exhibited good antimicrobial activity against E. coli NBIMCC K12 407 and Bacillus subtilis NBIMCC 3562.
Biodegradable magnesium (Mg) alloys have drawn considerable attention for use in orthopedic implants, but their antibacterial activity and corrosion resistance still require improvement. In the ...present work, functional Ta2O5 (tantalum pentoxide) compact layers and PCL/MgO-Ag (poly (ε-caprolactone)/magnesium oxide-silver) nanofiber porous layers were subsequently deposited on Mg alloys via reactive magnetron sputtering and electrospinning, respectively, to improve anticorrosion and antibacterial performance. Sputter coating of the Ta2O5 resulted in a thick layer (∼1 μm) with an amorphous structure and high adhesive strength. The nanostructure exhibited bubble-like patterns with no obvious nano-cracks, nano-porosities, or pinholes. The electrospun PCL/MgO-Ag nanofiber coating was porous, smooth, and plain with no obvious beads. In vitro corrosion tests demonstrated the PCL/MgO-Ag nanofiber-coated alloy had greater corrosion resistance than a Ta2O5 sputter-coated alloy or uncoated Mg alloy. The additional electrospun PCL/MgO-Ag nanofiber coating also had greater antibacterial behavior toward Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria than the Ta2O5-coated or uncoated alloy specimens. Increasing the MgO-Ag concentration of the nanofibers from 1 to 3 wt% increased antibacterial activity. The combination of Ta2O5 and PCL/MgO-Ag nanofiber coatings on Mg alloys may therefore have potential applications for reducing bone infection as related to orthopedic implants for bone repair.
The adverse impact of emerging pollutants (such as antibiotics) on water quality and subsequently on the ecosystem makes their removal very important. Herein, peanut husk (a low-cost material) was ...modified with betaine via a simple synthetic route to form a novel adsorbent (PN-Bet). The efficiency of PN-Bet for the removal of trimethoprim in solution was carried out via the batch and column method. Results from the batch studies indicated that factors such as initial concentration, solution pH and temperature had an influence on the uptake of TMP onto PN-Bet. A maximum monolayer adsorption capacity of 37.6 ± 1.5 mg g–1 (at 293 K) according to the Langmuir model was recorded with the process being exothermic in nature. Kinetic studies showed that both pseudo-first kinetic model and pseudo-second order kinetic model could describe the adsorption process indicating the complexity of the process. PN-Bet also showed some removal efficiency towards TMP in real water samples. The feasibility of PN-Bet for industrial applications was confirmed via the fixed-bed adsorption studies with the Clark model best describing the adsorption process. The facile synthetic route employed in this study involving the use of a low-cost material under benign environmental condition can help address some of the challenges associated with some reported adsorbents for the removal of TMP. Also, the development of this adsorbent with antibacterial and good reusability properties as well as high removal efficiency for TMP can serve as a model for the development of other novel adsorbents for the sequestration of both chemical and biological pollutants in wastewater.
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Plant-derived biomass adhesives are increasingly in demand to replace traditional non-biodegradable petrochemical materials. However, the insufficient mechanical strengths and poor antibacterial ...activities of biomaterials severely limit their applicability. Inspired by the amphiphilic characteristics of mussel protein, a dual-crosslinking strategy is reported here for preparing soy meal (SM)-based adhesives with excellent adhesion and antibacterial properties. Specifically, castor oil containing abundant hydroxyl groups was used to prepare the cationic waterborne polyurethane (WPU) dispersion. Subsequently, the dynamic glue bridges were synthesized from the tannic acid-functionalized borax (TA@BA) complexes via multiple coordination bonds. Finally, the enhanced cross-linking network system was then constructed in the protein matrix based on the synergy of dynamic covalent bonds, electrostatic interactions, and hydrogen bonds. As a result, the wet strength of the resultant adhesive significantly increased by 154.77% compared to the SM adhesive. Additionally, the resultant adhesive exhibited remarkably enhanced thermal stability, flame retardancy, and water resistance. Based on the synergistic effect of the cationic WPU, polyphenol components, and borate groups, the SM/WPU/TA@BA adhesive exhibited desirable anti-mildew and antibacterial properties. This biomimetic dual-crosslinking design therefore provides a novel and facile strategy for the preparation of high-performance biopolymer adhesives used in the fields of biology and engineering.
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•A bioinspired dual-crosslinking strategy is used to prepare protein-based adhesives.•The cationic waterborne dispersion was synthesized from vegetable castor oil.•A dynamic glue bridge was formed by incorporating tannic acid-functionalized borax.•The water resistance of the protein-based composites was significantly improved.•The hybrid adhesive showed enhanced antibacterial properties and flame retardancy.
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