scholarly journals Preclinical Study of a Multi-Layered Antimicrobial Patch Based on Thin Nanocomposite Amorphous Diamond Like Carbon Films with Embedded Silver Nanoparticles

Materials ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3180
Author(s):  
Tadas Juknius ◽  
Indrė Juknienė ◽  
Tomas Tamulevičius ◽  
Modestas Ružauskas ◽  
Ina Pamparienė ◽  
...  
Keyword(s):  
Thin Films ◽  
Silver Nanoparticles ◽  
Preclinical Study ◽  
Film Deposition ◽  
Ion Accumulation ◽  
Silver Ion ◽  
Resistant Bacteria ◽  
Diamond Like Carbon ◽  
Accumulation Layer ◽  
Scanning Electron

A growing number of severe infections are related to antibiotic-resistant bacteria, therefore, in recent years, alternative antimicrobial materials based on silver nanoparticles (NPs) attracted a lot of attention. In the current research, we present a medical patch prototype containing diamond-like carbon nanocomposite thin films doped with silver nanoparticles (DLC:Ag), as a source of silver ions, and an aqueous mass of the gelatin/agar mixture as a silver ion accumulation layer. The DLC:Ag thin films with 3.4 at.% of silver were deposited on synthetic silk employing reactive unbalanced DC magnetron sputtering of the silver target with argon ions performed in the acetylene gas atmosphere. The average size of the silver nanoparticles as defined by scanning electron microscope was 24 nm. After the film deposition, the samples were etched with RF oxygen plasma, aiming at efficient silver ion release in aqueous media from the nanocomposite film. In the patch prototype, a mixture of agar and gelatin was applied in silicone carrier with cavities, acting as a silver ion accumulation layer that further enhanced the antimicrobial efficiency. It was found that the DLC:Ag thin film on the silk after soaking in water for 24 h was able to release up to 4 ppm of Ag. The microbiological experiments using S. aureus bacteria were performed with the patch prototype and the silver ion saturated water, demonstrated the inactivation of 99% and 79% of bacteria, respectively. Scanning electron microscopy analysis showed that silver NPs destroyed the bacteria cell and the bacteria affected by Ag ions had spots and perforated cell wall areas with cytoplasm leakage out was obtained. A preliminary preclinical study using the laboratory animals demonstrated that using the patch prototype, the methicillin-resistant S. aureus (MRSA)-infected wound on skin surface healed faster compared with control and was able to kill all MRSA bacteria strains in the wound’s bed after 72 h of treatment.

Characterization of Sputtered Films using the Scanning Electron Microscope

1973 ◽  
Vol 31 ◽  
pp. 44-45
Author(s):  
R. F. Schneidmiller ◽  
W. F. Thrower ◽  
C. Ang
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Sputtered Films ◽  
Plasma Sputtering ◽  
Microelectronic Devices ◽  
Control Film ◽  
Scanning Electron

Solid state materials in the form of thin films have found increasing structural and electronic applications. Among the multitude of thin film deposition techniques, the radio frequency induced plasma sputtering has gained considerable utilization in recent years through advances in equipment design and process improvement, as well as the discovery of the versatility of the process to control film properties. In our laboratory we have used the scanning electron microscope extensively in the direct and indirect characterization of sputtered films for correlation with their physical and electrical properties.Scanning electron microscopy is a powerful tool for the examination of surfaces of solids and for the failure analysis of structural components and microelectronic devices.

Observations on the growth of YBa2Cu3O7-δ thin films on MgO by pulsed-laser ablation

1991 ◽  
Vol 49 ◽  
pp. 1068-1069
Author(s):  
M. Grant Norton ◽  
C. Barry Carter
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Laser Ablation ◽  
Substrate Surface ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Laser Ablation Process ◽  
Deposition Parameters

Pulsed-laser ablation has been widely used to produce high-quality thin films of YBa2Cu3O7-δ on a range of substrate materials. The nonequilibrium nature of the process allows congruent deposition of oxides with complex stoichiometrics. In the high power density regime produced by the UV excimer lasers the ablated species includes a mixture of neutral atoms, molecules and ions. All these species play an important role in thin-film deposition. However, changes in the deposition parameters have been shown to affect the microstructure of thin YBa2Cu3O7-δ films. The formation of metastable configurations is possible because at the low substrate temperatures used, only shortrange rearrangement on the substrate surface can occur. The parameters associated directly with the laser ablation process, those determining the nature of the process, e g. thermal or nonthermal volatilization, have been classified as ‘primary parameters'. Other parameters may also affect the microstructure of the thin film. In this paper, the effects of these ‘secondary parameters' on the microstructure of YBa2Cu3O7-δ films will be discussed. Examples of 'secondary parameters' include the substrate temperature and the oxygen partial pressure during deposition.

Electron energy loss spectroscopy of diamond-like carbon thin films

1992 ◽  
Vol 50 (2) ◽  
pp. 1272-1273
Author(s):  
J. Kulik ◽  
Y. Lifshitz ◽  
G.D. Lempert ◽  
S. Rotter ◽  
J.W. Rabalais ◽  
...  
Keyword(s):  
Thin Films ◽  
Energy Loss ◽  
Electron Energy ◽  
Ion Beam ◽  
Diamond Like Carbon ◽  
Ion Beam Deposition ◽  
Chemistry Research ◽  
Carbon Thin Films ◽  
Electron Energy Loss ◽  
Beam Deposition

Carbon thin films with diamond-like properties have generated significant interest in condensed matter science in recent years. Their extreme hardness combined with insulating electronic characteristics and high thermal conductivity make them attractive for a variety of uses including abrasion resistant coatings and applications in electronic devices. Understanding the growth and structure of such films is therefore of technological interest as well as a goal of basic physics and chemistry research. Recent investigations have demonstrated the usefulness of energetic ion beam deposition in the preparation of such films. We have begun an electron microscopy investigation into the microstructure and electron energy loss spectra of diamond like carbon thin films prepared by energetic ion beam deposition.The carbon films were deposited using the MEIRA ion beam facility at the Soreq Nuclear Research Center in Yavne, Israel. Mass selected C+ beams in the range 50 to 300 eV were directed onto Si {100} which had been etched with HF prior to deposition.

Imaging magnetic microstructure with SEMPA

1993 ◽  
Vol 51 ◽  
pp. 1032-1033
Author(s):  
M. H. Kelley ◽  
J. Unguris ◽  
R. J. Celotta ◽  
D. T. Pierce
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Scanning Electron Microscopy ◽  
Sandwich Structure ◽  
Magnetic Coupling ◽  
Polarization Analysis ◽  
Secondary Electrons ◽  
Magnetic Microstructure ◽  
Escape Depth ◽  
Scanning Electron

By measuring the spin polarization of secondary electrons generated in a scanning electron microscope, scanning electron microscopy with polarization analysis (SEMPA) can directly image the magnitude and direction of a material’s magnetization. Because the escape depth of the secondaries is only on the order of 1 nm, SEMPA is especially well-suited for investigating the magnetization of ultra-thin films and surfaces. We have exploited this feature of SEMPA to study the magnetic microstrcture and magnetic coupling in ferromagnetic multilayers where the layers may only be a few atomic layers thick. For example, we have measured the magnetic coupling in Fe/Cr/Fe(100) and Fe/Ag/Fe(100) trilayers and have found that the coupling oscillates between ferromagnetic and antiferromagnetic as a function of the Cr or Ag spacer thickness.The SEMPA apparatus has been described in detail elsewhere. The sample consisted of a magnetic sandwich structure with a wedge-shaped interlayer as shown in Fig. 1.

Application of Capillary Discharge Technique for Deposition of Diamond-Like Carbon Thin Films (2nd Report)

2013 ◽  
Vol 133 (5) ◽  
pp. 293-299
Author(s):  
Kiyotoshi Fujii ◽  
Etsuo Fujiwara ◽  
Masayoshi Shimizu ◽  
Shozo Inoue
Keyword(s):  
Thin Films ◽  
Capillary Discharge ◽  
Diamond Like Carbon ◽  
Carbon Thin Films

Synergistic Antibacterial Efficacy of Biogenic Synthesized Silver Nanoparticles using Ajuga bractosa with Standard Antibiotics: A Study Against Bacterial Pathogens

2020 ◽  
Vol 21 (3) ◽  
pp. 206-218 ◽  
Author(s):  
Sadia Nazer ◽  
Saiqa Andleeb ◽  
Shaukat Ali ◽  
Nazia Gulzar ◽  
Tariq Iqbal ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Bacterial Pathogens ◽  
Potential Effect ◽  
Innovative Technology ◽  
Multi Drug Resistance ◽  
Phytochemical Screening ◽  
Cell Proliferation Inhibition ◽  
Agar Well Diffusion Assay ◽  
Scanning Electron

Background: Multi-drug resistance in bacterial pathogens is a major concern of today. Green synthesis technology is being used to cure infectious diseases. Objectives: The aim of the current research was to analyze the antibacterial, antioxidant, and phytochemical screening of green synthesized silver nanoparticles using Ajuga bracteosa. Methods: Extract of A. bracteosa was prepared by maceration technique. Silver nanoparticles were synthesized using A. bracteosa extract and were confirmed by UV-Vis spectrophotometer, Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The antibacterial, anti-biofilm, cell proliferation inhibition, TLC-Bioautography, TLC-Spot screening, antioxidant, and phytochemical screening were also investigated. Results: UV-Vis spectrum and Scanning electron microscopy confirmed the synthesis of green nanoparticles at 400 nm with tube-like structures. FTIR spectrum showed that functional groups of nanoparticles have a role in capping and stability of AgNP. Agar well diffusion assay represented the maximum antibacterial effect of ABAgNPs against Escherichia coli, Klebsiella pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, and Pseudomonas aeruginosa at 0.10 g/mL concentration compared to ABaqu. Two types of interactions among nanoparticles, aqueous extract, and antibiotics (Synergistic and additive) were recorded against tested pathogens. Crystal violet, MTT, TLC-bio-autography, and spot screening supported the findings of the antibacterial assay. Highest antioxidant potential effect in ABaqu was 14.62% (DPPH) and 13.64% (ABTS) while 4.85% (DPPH) and 4.86% (ABTS) was recorded in ABAgNPs. Presence of phytochemical constituents showed pharmacological importance. Conclusion: It was concluded that green synthesis is an innovative technology in which natural products are conjugated with metallic particles and are used against infectious pathogens. The current research showed the significant use of green nanoparticles against etiological agents.

scholarly journals Biofilm Inhibition and Antimicrobial Properties of Silver-Ion-Exchanged Zeolite A against Vibrio spp Marine Pathogens

2021 ◽  
Vol 11 (12) ◽  
pp. 5496
Author(s):  
Zarina Amin ◽  
Nur Ariffah Waly ◽  
Sazmal Effendi Arshad
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Antimicrobial Properties ◽  
Immune Defense ◽  
Silver Ion ◽  
Bacterial Disease ◽  
Zeolite A ◽  
Biofilm Inhibition ◽  
Volcanic Origin ◽  
Scanning Electron

A challenging problem in the aquaculture industry is bacterial disease outbreaks, which result in the global reduction in fish supply and foodborne outbreaks. Biofilms in marine pathogens protect against antimicrobial treatment and host immune defense. Zeolites are minerals of volcanic origin made from crystalline aluminosilicates, which are useful in agriculture and in environmental management. In this study, silver-ion-exchanged zeolite A of four concentrations; 0.25 M (AgZ1), 0.50 M (AgZ2), 1.00 M (AgZ3) and 1.50 M (AgZ4) were investigated for biofilm inhibition and antimicrobial properties against two predominant marine pathogens, V. campbelli and V. parahemolyticus, by employing the minimum inhibitory concentration (MIC) and crystal violet biofilm quantification assays as well as scanning electron microscopy. In the first instance, all zeolite samples AgZ1–AgZ4 showed antimicrobial activity for both pathogens. For V. campbellii, AgZ4 exhibited the highest MIC at 125.00 µg/mL, while for V. parahaemolyticus, the highest MIC was observed for AgZ3 at 62.50 µg/mL. At sublethal concentration, biofilm inhibition of V. campbelli and V. parahemolyticus by AgZ4 was observed at 60.2 and 77.3% inhibition, respectively. Scanning electron microscopy exhibited profound structural alteration of the biofilm matrix by AgZ4. This is the first known study that highlights the potential application of ion-exchanged zeolite A against marine pathogens and their biofilms.

scholarly journals The Synergistic Effect of Biosynthesized Silver Nanoparticles and Phage ZCSE2 as a Novel Approach to Combat Multidrug-Resistant Salmonella enterica

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 678
Author(s):  
Abdallah S. Abdelsattar ◽  
Rana Nofal ◽  
Salsabil Makky ◽  
Anan Safwat ◽  
Amera Taha ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Color Change ◽  
Antibacterial Properties ◽  
Multidrug Resistant ◽  
Inhibitory Effect ◽  
Health Concern ◽  
Resistant Bacteria ◽  
Mortality And Morbidity ◽  
Novel Approach ◽  
Transmission Electron

The emergence and evolution of antibiotic-resistant bacteria is considered a public health concern. Salmonella is one of the most common pathogens that cause high mortality and morbidity rates in humans, animals, and poultry annually. In this work, we developed a combination of silver nanoparticles (AgNPs) with bacteriophage (phage) as an antimicrobial agent to control microbial growth. The synthesized AgNPs with propolis were characterized by testing their color change from transparent to deep brown by transmission electron microscopy (TEM) and Fourier-Transform Infrared Spectroscopy (FTIR). The phage ZCSE2 was found to be stable when combined with AgNPs. Both minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated for AgNPs, phage, and their combination. The results indicated that MIC and MBC values were equal to 23 µg/mL against Salmonella bacteria at a concentration of 107 CFU/mL. The combination of 0.4× MIC from AgNPs and phage with Multiplicity of Infection (MOI) 0.1 showed an inhibitory effect. This combination of AgNPs and phage offers a prospect of nanoparticles with significantly enhanced antibacterial properties and therapeutic performance.

Studies on Magnetron-Sputtered NiO/Si3N4 Thin Films

2018 ◽  
Vol 17 (03) ◽  
pp. 1760039
Author(s):  
K. M. Dhanisha ◽  
M. Manoj Christopher ◽  
M. Abinaya ◽  
P. Deepak Raj ◽  
M. Sridharan
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Smooth Surface ◽  
Deposition Time ◽  
Si Substrate ◽  
X Ray ◽  
Coating Time ◽  
Deposited Films ◽  
Nio Films ◽  
Scanning Electron

The present work deals with NiO/Si3N4 layers formed by depositing nickel oxide (NiO) thin films over silicon nitrate (Si3N[Formula: see text] thin films. NiO films were coated on Si3N4-coated Si substrate using magnetron sputtering method by changing duration of coating time and were analyzed using X-ray diffractometer, field emission-scanning electron microscopy, UV–Vis spectrophotometer and four-point probe method to study the influence of thickness on physical properties. Crystallinity of the deposited films increases with increase in thickness. All films exhibited spherical-like structure, and with increase in deposition time, grains are coalesced to form smooth surface morphology. The optical bandgap of NiO films was found to decrease from 3.31[Formula: see text]eV to 3.22[Formula: see text]eV with upsurge in the thickness. The film deposited for 30[Formula: see text]min exhibits temperature coefficient resistance of [Formula: see text]1.77%/[Formula: see text]C as measured at 80[Formula: see text]C.

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