scholarly journals Photothermal-assisted antibacterial application of GO-Ag against clinical isolated MDR E. coli

2019 ◽  
Author(s):  
Yuqing Chen ◽  
Wei Wu ◽  
Zeqiao Xu ◽  
Cheng Jiang ◽  
Shuang Han ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Near Infrared ◽  
Antibacterial Effect ◽  
Luria Bertani ◽  
Fluorescent Imaging ◽  
Photothermal Effect ◽  
Antibacterial Efficiency ◽  
E Coli ◽  
Morphology Characterization

Abstract Background: Treatment of multidrug-resistant (MDR) bacterial infection is a great challenge in public health. Herein, we provide a solution to this problem with the use of graphene oxide-silver (GO-Ag) nanocomposites as anti-bacterial agent. Methods: Following established protocols, silver nanoparticles were grown on graphene oxide sheets. Then, a series of in-vitro studies were conducted to validate the antibacterial efficiency of the GO-Ag nanocomposites against clinical MDR Escherichia coli (E. coli) strains. Firstly, minimum inhibitory concentrations (MICs) of different antimicrobials were tested against MDR E. Coli strains. Then, bacteria viability assessments were conducted with different nanomaterials in Luria-Bertani (LB) broth. Afterwards, photothermal irradiation was conducted on MDR E. coli with lower GO-Ag concentration. At last, fluorescent imaging and morphology characterization using scanning electron microscope (SEM) were done to find the possible cause of antibacterial effect. Results: GO-Ag nanocomposites showed the highest antibacterial efficiency among tested antimicrobials. Synergetic antibacterial effect was observed in GO-Ag nanocomposites treated group. The remained bacteria viabilities were 4.4% and 4.1% respectively for different bacteria strains with GO-Ag concentration at 14.0 µg mL-1. In addition, GO-Ag nanocomposites have strong absorption in the near-infrared field and can convert the electromagnetic energy to heat. With the use of this photothermal effect, effective sterilization could be achieved using GO-Ag nanocomposites concentration as low as 7.0 µg mL-1. Fluorescent imaging and morphology characterization were used to analyze bacteria living status, which uncovered that bacteria integrity was disrupted after GO-Ag nanocomposites treatment. Conclusions: GO-Ag nanocomposites are proved to be efficient antibacterial agent against multi-drug resistant E. coli. Their strong antibacterial effect arises from inherent antibacterial property and photothermal effect that provides aid for bacteria killing.

scholarly journals Photothermal-assisted antibacterial application of graphene oxide-Ag nanocomposites against clinically isolated multi-drug resistant Escherichia coli

2020 ◽  
Vol 7 (7) ◽  
pp. 192019 ◽  
Author(s):  
Yuqing Chen ◽  
Wei Wu ◽  
Zeqiao Xu ◽  
Cheng Jiang ◽  
Shuang Han ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Silver Nanoparticles ◽  
Graphene Oxide ◽  
Group Treatment ◽  
Antibacterial Agent ◽  
Multidrug Resistant ◽  
Photothermal Effect ◽  
Antibacterial Efficiency ◽  
E Coli

In the field of public health, treatment of multidrug-resistant (MDR) bacterial infection is a great challenge. Herein, we provide a solution to this problem with the use of graphene oxide-silver (GO-Ag) nanocomposites as antibacterial agent. Following established protocols, silver nanoparticles were grown on graphene oxide sheets. Then, a series of in vitro studies were conducted to validate the antibacterial efficiency of the GO-Ag nanocomposites against clinical MDR Escherichia coli ( E. coli ) strains. GO-Ag nanocomposites showed the highest antibacterial efficiency among tested antimicrobials (graphene oxide, silver nanoparticles, GO-Ag), and synergetic antibacterial effect was observed in GO-Ag nanocomposites treated group. Treatment with 14.0 µg ml −1 GO-Ag could greatly inhibit bacteria growth; remaining bacteria viabilities were 4.4% and 4.1% for MDR-1 and MDR-2 E. coli bacteria, respectively. In addition, with assistance of photothermal effect, effective sterilization could be achieved using GO-Ag nanocomposites as low as 7.0 µg ml −1 . Fluorescence imaging and morphology characterization uncovered that bacteria integrity was disrupted after GO-Ag nanocomposites treatment. Cytotoxicity results of GO-Ag using human-derived cell lines (HEK 293T, Hep G2) suggested more than 80% viability remained at 7.0 µg ml −1 . All the results proved that GO-Ag nanocomposites are efficient antibacterial agent against multidrug-resistant E. coli .

scholarly journals Chitosan/Silver Nanoparticle/Graphene Oxide Nanocomposites with Multi-drug Release, Antimicrobial, and Photothermal Conversion Functions

2021 ◽  
Author(s):  
Zheng Su ◽  
Daye Sun ◽  
Li Zhang ◽  
Miaomiao He ◽  
Yulin Jiang ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Graphene Oxide ◽  
Drug Release ◽  
Composite System ◽  
Near Infrared ◽  
Environment Friendly ◽  
Photothermal Conversion ◽  
E Coli ◽  
Nanocomposite System ◽  
Dual Drug

In this work, we designed and fabricated a multifunctional nanocomposite system which consists of chitosan, raspberry-like silver nanoparticles and graphene oxide. Room temperature atmospheric pressure microplasma (RT-APM) process provides a rapid, facile, and environment-friendly method for introducing silver nanoparticles into the composite system. By loading different drugs onto the polymer matrix and/or graphene oxide, our composite can achieve a pH controlled dual drug release with release profile specific to the drugs used. In addition to its strong antibacterial ability against E. coli and S. aureus, our composite also demonstrates excellent photothermal conversion effect under irradiation of near infrared lasers. These unique functionalities point to it’s the potential of nanocomposite system in multiple applications areas such as multimodal therapeutics in healthcare, water treatment, and anti-microbial, etc.

scholarly journals Antimicrobial and Antibiofilm Properties of Graphene Oxide on Enterococcus faecalis

Antibiotics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 692
Author(s):  
Cecilia Martini ◽  
Francesca Longo ◽  
Raffaella Castagnola ◽  
Luca Marigo ◽  
Nicola Maria Grande ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Enterococcus Faecalis ◽  
Antibacterial Properties ◽  
Luria Bertani ◽  
Bacterial Suspension ◽  
Adhesion Properties ◽  
High Antibacterial Activity ◽  
Luria Bertani Broth ◽  
Bacterial Film

The aim of this study was to evaluate the antibacterial properties of graphene oxide (GO) against Enterococcus faecalis in vitro conditions and when used to coat dentin surface to prevent E. faecalis adhesion. The ATCC strain of E. faecalis 29212 has been used to perform a viability test. The pellet was suspended in ultrapure water, NaCl, PBS buffer, CaCl2 and MgCl2, Luria−Bertani broth solutions. The viability was evaluated by the colony forming unit counting method. Atomic force microscopy images and the measure of surface zeta potential variation were analyzed. Dentin discs were covered with a film of GO (n = 15) or were not treated (n = 15). Bacterial suspension was added to each sample of dentine discs and microbial counts were calculated. Statistically significant differences between two groups were assessed by a two-tailed unpaired t-test. Bacteria cell morphology was investigated with scanning electron microscopy. The highest growth inhibition was obtained in ddH2O and CaCl2 solution while, in PBS and NaCl, GO had poor antibacterial efficacy with a growth enhancing effect in the latter. GO on dentin discs demonstrated high antibacterial activity. GO film has demonstrated acceptable adhesion properties to root dentin and a role in the inhibition of bacterial film proliferation and biofilm formation.

scholarly journals Chitosan-based nanoparticles sustenance and potentiation of the antibacterial effect of ampicillin against drug resistance among strains of Escherichia coli

Bio-Research ◽  
2020 ◽  
Vol 18 (2) ◽  
Author(s):  
EB Onuigbo ◽  
C Anozie-Ikeanyi ◽  
NE Edeh ◽  
CO Eze ◽  
TH Gugu
Keyword(s):  
Drug Resistance ◽  
Drug Release ◽  
Encapsulation Efficiency ◽  
Antibacterial Effect ◽  
Sodium Tripolyphosphate ◽  
Chitosan Nanoparticles ◽  
In Vitro Drug Release ◽  
E Coli ◽  
Ampicillin Trihydrate

The study seeks to evaluate nanoparticles based on chitosan for enhanced delivery of ampicillin in plasmid-mediated drug resistance. Serial dilutions of a mixed population of E. coli was plated on nutrient agar and streaked on Replica-plate 25 random colonies using MacConkey agar with or without ampicillin (100 µg/ml) daily for 96 h. Nanoparticles were prepared by cross-linking chitosan with sodium tripolyphosphate with ampicillin trihydrate adsorbed. Three different batches were prepared for optimization. The nanoparticles were optimized based on encapsulation efficiency, in vitro drug release, pH stability and microbiological assay using two laboratory strains of E. coli. Increased resistance to ampicillin due to possible plasmid transfer was established in vitro after 96 h. The encapsulation efficiency of the three batches was between 21-57 %. The drug release showed a burst effect and slow extended release over 8 h and reached a peak of about 19 % release at the 6 and 7 h in Batch A, B and C. The pH of the particles was stable over a period of 6 d. The nanoparticles containing only 0.075 mg of ampicillin dropped in an agar well plate inoculated with 1 ml of E. coli J62 lac pro trp hispFlac::Tn3 (AmpR) gave an IZD of ≥ 25 mm. Chitosan nanoparticles holds good potentials in potentiating the antibacterial effect of ampicillin against possible plasmid-mediated drug resistance

Multifunctional graphene oxide for bioimaging: emphasis on biological research

2017 ◽  
Vol 9 (2) ◽  
Author(s):  
Do Won Hwang ◽  
Byung Hee Hong ◽  
Dong Soo Lee
Keyword(s):  
Graphene Oxide ◽  
Targeted Delivery ◽  
Near Infrared ◽  
Biological Research ◽  
Natural Interaction ◽  
Drug Delivery Carrier ◽  
Wide Range ◽  
Surface Enhanced Raman

AbstractGraphene oxide (GO) nanomaterials offer a wide range of bioimaging applicability. Almost complete quenching ability of fluorescence by GO and natural interaction of GO with single stranded nucleic acid made GO a useful and intriguing multifunctional nanoplatform both as a biosensor for in vitro microplate diagnostics and as a drug delivery carrier for targeted delivery. GO’s large surface area and strong near infrared absorbance contribute to enhancement of a therapeutic effect with abundant loading of drugs for possible photothermal and photodynamic therapy. Bioimaging capability of GO made it a good theranostic tool, while enabling tracing in vivo pharmacokinetics during concurrent treatment. Fluorescence, either signal on or off, Raman and surface-enhanced Raman scattering (SERs), photoacoustic, and radionuclide imaging modalities can be used for theranostic purposes using GO nanomaterials. In this review, we highlight current applications of GO for bioimaging that are classified into in vitro microplate, in vitro cellular and in vivo bioimaging.

scholarly journals Antibacterial and fungicidal effect of ethanol extracts from Juniperus sabina, Chamaecyparis lawsoniana, Pseudotsuga menziesii and Cephalotaxus harringtonia

2020 ◽  
Vol 11 (1) ◽  
pp. 105-109
Author(s):  
V. V. Zazharskyi ◽  
P. О. Davydenko ◽  
O. М. Kulishenko ◽  
I. V. Borovik ◽  
A. M. Kabar ◽  
...  
Keyword(s):  
Pseudotsuga Menziesii ◽  
Antibacterial Effect ◽  
Zone Of Inhibition ◽  
E Coli ◽  
Inhibition Of Growth ◽  
Chamaecyparis Lawsoniana ◽  
Ethanol Extracts ◽  
Juniperus Sabina

We determined a high antibacterial effect of ethanol extracts of four species of gymnosperms (Juniperus sabina, Chamaecyparis lawsoniana, Pseudotsuga menziesii and Cephalotaxus harringtonia) against 23 strains of bacteria of families Enterobacteriaceae (Escherichia coli, Enterococcus faecalis, Salmonella typhimurium, S. adobraco, Proteus vulgaris, P. mirabilis, Serratia marcescens, Klebsiella pneumoniae), Staphylococcaceae (Staphylococcus aureus, S. epidermidis), Yersiniaceae (Yersinia enterocolitica), Bacillaceae (Bacillus subtilis, B. cereus), Listeriaceae (Listeria ivanovi, L. іnnocua, L. monocytogenes), Corynebacteriaceae (Corynebacterium xerosis), Campylobacteraceae (Campylobacter jejuni), Nocardiaceae (Rhodococcus equi), Pseudomonadaceae (Pseudomonas аeruginosa) and one strain of fungi of the Saccharomycetaceae family (Candida albicans). The experiment in vitro revealed zone of inhibition of growth of colonies, measuring over 8 mm, produced by ethanol extracts from J. sabina against seven species of bacteria (S. aureus, B. subtilis, B. cereus, L. іnnocua, C. xerosis, Rh. equi and P. аeruginosa), Ch. lawsoniana – against five species (E. coli, B. subtilis, L. іnnocua and Rh. equi), P. menziesii –two species (Rh. equi and P. mirabilis), C. harringtonia – ten species of microorganisms (E. coli, S. aureus, S. epidermidis, L. ivanovi, L. monocytogenes, C. xerosis, C. jejuni, P. vulgaris, S. marcescens and C. albicans). As a result of the research, the most promising plants for further in vivo study of antibacterial activity were C. harringtonia and J. sabina.

scholarly journals Broad-spectrum Antimicrobial ZnMintPc Encapsulated in Magnetic-nanocomposites with Graphene Oxide/MWCNTs Based on Bimodal Action of Photodynamic and Photothermal Effect

2022 ◽  
Author(s):  
Coralia Fabiola Cuadrado ◽  
Antonio Díaz-Barrios ◽  
Kleber Orlando Campana ◽  
Eric Cardona Romani ◽  
Francisco Javier Quiroz ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Broad Spectrum ◽  
Antimicrobial Agents ◽  
Zinc Phthalocyanine ◽  
Precipitation Method ◽  
Photothermal Effect ◽  
Magnetic Nanocomposites ◽  
Second Phase ◽  
Glycol Diacrylate

Microbial diseases have been declared one of the main threats to humanity, which is why, in recent years, great interest has been generated in the development of nanocomposites with antimicrobial capacity. In the present work, two magnetic nanocomposites, based on Graphene Oxide (GO) and Multiwall Carbon Nanotubes (MWCNTs) were studied. The synthesis of these magnetic nanocomposites consisted of three phases: first, the synthesis of Iron Magnetic Nanoparticles (MNPs) was carried out in the presence of MWCNTs and GO using the Co-precipitation method. The second phase consisted of the adsorption of photosensitizer menthol-Zinc phthalocyanine (ZnMintPc) into MWCNTs and GO, and the third phase was the encapsulation in poly (N-vinylcaprolactam-co-poly(ethylene glycol diacrylate)) poly (VCL-co-PEGDA) polymer VCL/PEGDA a biocompatible hydrogel, in order to obtain the magnetic nanocomposites: VCL/PEGDA-MNPs-MWCNTs-ZnMintPc and VCL/PEGDA-MNPs-GO-ZnMintPc. In vitro studies were carried out using Escherichia coli and Staphylococcus aureus bacteria and the Candida albicans yeast based on the PTT/PDT effect. This research describes the optical, morphological, magnetic and photophysical characterizations of nanocomposites and their application as antimicrobial agents. It was evaluated the antimicrobial effect of magnetics nanocomposites based on the Photodynamic/Photothermal (PDT/PTT) effect; for this purpose, doses of 65 mW cm-2 at 630 nm of light were used. The VCL/PEGDA-MNPs-GO-ZnMintPc nanocomposite was able to eliminate colonies of E. coli and S. aureus, while VCL/PEGDA-MNPs-MWCNTs-ZnMintPc nanocomposite was able to eliminate the three types of microorganisms; consequently, the latter is considered a broad-spectrum of antimicrobial agent in PDT and PTT.

scholarly journals Hyaluronic acid modified covalent organic polymers for efficient targeted and oxygen-evolved phototherapy

2020 ◽  
Author(s):  
Fangpeng Shu ◽  
Taowei Yang ◽  
Xuefeng Zhang ◽  
Wenbin Chen ◽  
Kaihui Wu ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Colloidal Stability ◽  
Near Infrared ◽  
Combined Therapy ◽  
Tumor Therapy ◽  
Photothermal Effect ◽  
Organic Polymers ◽  
New Paradigm

Abstract The integration of multiple functions with organic polymers-based nanoagent holds great potential to potentiate its therapeutic efficacy, but still remains challenges. In the present study, we design and prepare an organic nanoagent with oxygen-evolved and targeted ability for improved phototherapeutic efficacy. The iron ions doped poly diaminopyridine (FeD) is prepared by oxidize polymerization and modified with hyaluronic acid (HA). The obtained FeDH appears uniform morphology and size. Its excellent colloidal stability and biocompatibility are demonstrated. Specifically, the FeDH exhibits catalase-like activity in the presence of hydrogen peroxide. After loading of photosensitizer indocyanine green (ICG), the ICG@FeDH not only demonstrates favorable photothermal effect, but also shows improved generation ability of reactive oxygen species (ROS) under near-infrared laser irradiation. Moreover, the targeted uptake of ICG@FeDH in tumor cells is directly observed. As consequence, the superior phototherapeutic efficacy of the targeted ICG@FeDH over non-targeted counterparts is also confirmed in vitro and in vivo. Hence, the results demonstrate that the developed nanoagent rationally integrates the targeted ability, oxygen-evolved capacity and combined therapy in one system, offering a new paradigm of polymer-based nanomedicine for tumor therapy.

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