Bactericides Based on Copper Nanoparticles Restrain Growth of Important Plant Pathogens

Copper nanoparticles (CuNPs) can offer an alternative to conventional copper bactericides and possibly slow down the development of bacterial resistance. This will consequently lower the accumulation rate of copper to soil and water and lower the environmental and health burden imposed by copper application. Physical and chemical methods have been reported to synthesize CuNPs but their use as bactericides in plants has been understudied. In this study, two different CuNPs products have been developed, CuNP1 and CuNP2 in two respective concentrations (1500 ppm or 300 ppm). Both products were characterized using Dynamic Light Scattering, Transmission Electron Microscopy, Attenuated Total Reflection measurements, X-ray Photoelectron Spectroscopy, X-ray Diffraction and Scattering, and Laser Doppler Electrophoresis. They were evaluated for their antibacterial efficacy in vitro against the gram-negative species Agrobacterium tumefaciens, Dickeya dadantii, Erwinia amylovora, Pectobacterium carotovorum, Pseudomonas corrugata, Pseudomonas savastanoi pv. savastanoi, and Xanthomonas campestris pv. campestris. Evaluation was based on comparisons with two commercial bactericides: Kocide (copper hydroxide) and Nordox (copper oxide). CuNP1 inhibited the growth of five species, restrained the growth of P. corrugata, and had no effect in X. c. pv campestris. MICs were significantly lower than those of the commercial formulations. CuNP2 inhibited the growth of E. amylovora and restrained growth of P. s. pv. savastanoi. Again, its overall activity was higher compared to commercial formulations. An extensive in vitro evaluation of CuNPs that show higher potential compared to their conventional counterpart is reported for the first time and suggests that synthesis of stable CuNPs can lead to the development of low-cost sustainable commercial products.

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Enhanced Antibacterial Activity of CuS-BSA/Lysozyme under Near Infrared Light Irradiation

Nanomaterials ◽

10.3390/nano11092156 ◽

2021 ◽

Vol 11 (9) ◽

pp. 2156

Author(s):

Abir Swaidan ◽

Sena Ghayyem ◽

Alexandre Barras ◽

Ahmed Addad ◽

Sabine Szunerits ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Near Infrared ◽

Low Cost ◽

Drug Carrier ◽

Effective Means ◽

Infrared Light ◽

Antibacterial Drug ◽

Bacterial Killing ◽

X Ray

The synthesis of multifunctional photothermal nanoagents for antibiotic loading and release remains a challenging task in nanomedicine. Herein, we investigated a simple, low-cost strategy for the preparation of CuS-BSA nanoparticles (NPs) loaded with a natural enzyme, lysozyme, as an antibacterial drug model under physiological conditions. The successful development of CuS-BSA NPs was confirmed by various characterization tools such as transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Lysozyme loading onto CuS-BSA NPs was evaluated by UV/vis absorption spectroscopy, Fourier-transform infrared spectroscopy (FTIR), zeta potential, and dynamic light scattering measurements. The CuS-BSA/lysozyme nanocomposite was investigated as an effective means for bacterial elimination of B. subtilis (Gram-positive) and E. coli (Gram-negative), owing to the combined photothermal heating performance of CuS-BSA and lysozyme release under 980 nm (0.7 W cm−2) illumination, which enhances the antibiotic action of the enzyme. Besides the photothermal properties, CuS-BSA/lysozyme nanocomposite possesses photodynamic activity induced by NIR illumination, which further improves its bacterial killing efficiency. The biocompatibility of CuS-BSA and CuS-BSA/Lysozyme was elicited in vitro on HeLa and U-87 MG cancer cell lines, and immortalized human hepatocyte (IHH) cell line. Considering these advantages, CuS-BSA NPs can be used as a suitable drug carrier and hold promise to overcome the limitations of traditional antibiotic therapy.

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Effect of C6-Volatiles on Bioluminescent Plant Pathogens

HortScience ◽

10.21273/hortsci.33.3.557d ◽

1998 ◽

Vol 33 (3) ◽

pp. 557d-557

Author(s):

Jennifer Warr ◽

Fenny Dane ◽

Bob Ebel

Keyword(s):

Biological Activity ◽

Bacterial Growth ◽

Xanthomonas Campestris ◽

Plant Pathogens ◽

Genetically Engineered ◽

The Other ◽

Computer Assisted ◽

Signal Molecules ◽

Low Concentrations

C6 volatile compounds are known to be produced by the plant upon pathogen attack or other stress-related events. The biological activity of many of these substances is poorly understood, but some might produce signal molecules important in host–pathogen interactions. In this research we explored the possibility that lipid-derived C6 volatiles have a direct effect on bacterial plant pathogens. To this purpose we used a unique tool, a bacterium genetically engineered to bioluminesce. Light-producing genes from a fish-associated bacterium were introduced into Xanthomonas campestris pv. campestris, enabling nondestructive detection of bacteria in vitro and in the plant with special computer-assisted camera equipment. The effects of different C6 volatiles (trans-2 hexanal, trans-2 hexen-1-ol and cis-3 hexenol) on growth of bioluminescent Xanthomonas campestris were investigated. Different volatile concentrations were used. Treatment with trans-2 hexanal appeared bactericidal at low concentrations (1% and 10%), while treatments with the other volatiles were not inhibitive to bacterial growth. The implications of these results with respect to practical use of trans-2 hexanal in pathogen susceptible and resistant plants will be discussed.

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Synthesis, characterization and in vitro cytotoxicity study of Co and Ni ferrite nanoparticles prepared by sol-gel method

SN Applied Sciences ◽

10.1007/s42452-021-04709-y ◽

2021 ◽

Vol 3 (7) ◽

Author(s):

Alexandre Pancotti ◽

Dener Pereira Santos ◽

Dielly Oliveira Morais ◽

Mauro Vinícius de Barros Souza ◽

Débora R. Lima ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Sol Gel ◽

Test Sample ◽

In Vitro Cytotoxicity ◽

Gel Method ◽

X Ray ◽

Sol Gel Method ◽

Transmission Electron ◽

Crystallite Sizes

AbstractIn this study, we report the synthesis and characterization of NiFe2O4 and CoFe2O4 nanoparticles (NPs) which are widely used in the biomedical area. There is still limited knowledge how the properties of these materials are influenced by different chemical routes. In this work, we investigated the effect of heat treatment over cytotoxicity of cobalt and niquel ferrites NPs synthesized by sol-gel method. Then the samples were studied using transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), Fourier Transform Infrared Spectroscopy Analysis (FTIR), and X-ray fluorescence (XRF). The average crystallite sizes of the particles were found to be in the range of 20–35 nm. The hemocompatibility (erythrocytes and leukocytes) was checked. Cytotoxicity results were similar to those of the control test sample, therefore suggesting hemocompatibility of the tested materials.

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Synthesis of Exosome-Based Fluorescent Gold Nanoclusters for Cellular Imaging Applications

International Journal of Molecular Sciences ◽

10.3390/ijms22094433 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4433

Author(s):

Eun Sung Lee ◽

Byung Seok Cha ◽

Seokjoon Kim ◽

Ki Soo Park

Keyword(s):

Photoelectron Spectroscopy ◽

Low Cost ◽

Stokes Shift ◽

Gold Nanoclusters ◽

Human Colon ◽

Cellular Imaging ◽

Metal Nanoclusters ◽

Human Colon Cancer ◽

X Ray ◽

High Concentrations

In recent years, fluorescent metal nanoclusters have been used to develop bioimaging and sensing technology. Notably, protein-templated fluorescent gold nanoclusters (AuNCs) are attracting interest due to their excellent fluorescence properties and biocompatibility. Herein, we used an exosome template to synthesize AuNCs in an eco-friendly manner that required neither harsh conditions nor toxic chemicals. Specifically, we used a neutral (pH 7) and alkaline (pH 11.5) pH to synthesize two different exosome-based AuNCs (exo-AuNCs) with independent blue and red emission. Using field-emission scanning electron microscopy, energy dispersive X-ray microanalysis, nanoparticle tracking analysis, and X-ray photoelectron spectroscopy, we demonstrated that AuNCs were successfully formed in the exosomes. Red-emitting exo-AuNCs were found to have a larger Stokes shift and a stronger fluorescence intensity than the blue-emitting exo-AuNCs. Both exo-AuNCs were compatible with MCF-7 (human breast cancer), HeLa (human cervical cancer), and HT29 (human colon cancer) cells, although blue-emitting exo-AuNCs were cytotoxic at high concentrations (≥5 mg/mL). Red-emitting exo-AuNCs successfully stained the nucleus and were compatible with membrane-staining dyes. This is the first study to use exosomes to synthesize fluorescent nanomaterials for cellular imaging applications. As exosomes are naturally produced via secretion from almost all types of cell, the proposed method could serve as a strategy for low-cost production of versatile nanomaterials.

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Chemical Structures of Native Oxides Formed During Wet Chemical Treatments on NH4F Treated Si(111) Surfaces

MRS Proceedings ◽

10.1557/proc-259-31 ◽

1992 ◽

Vol 259 ◽

Cited By ~ 3

Author(s):

Takeo Hattori ◽

Hiroki Ogawa

Keyword(s):

Photoelectron Spectroscopy ◽

Attenuated Total Reflection ◽

Native Oxide ◽

X Ray ◽

Chemical Treatments ◽

Chemical Structures ◽

Native Oxides ◽

Ft Ir ◽

Wet Chemical ◽

Silicon Interface

ABSTRACTChemical structures of native oxides formed during wet chemical treatments on NH4F treated Si(111) surfaces were investigated using X-ray Photoelectron Spectroscopy (XPS) and Fourier Transformed Infrared Attenuated Total Reflection(FT-IR-ATR). It was found that the amounts of Si-H bonds in native oxides and those at native oxide/silicon interface are negligibly small in the case of native oxides formed in H2SO4-H2O2-H2O solution. Based on this discovery, it was confirmed that native oxides can be characterized by the amount of Si-H bonds in native oxides. Furthermore, it was found that the combination of various wet chemical treatments with the treatment in NH4OH-H2O2-H2O solution results in the drastic decrease in the amount of Si-H bonds in native oxides.

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Lactoferrin/Calcium Phosphate-Modified Porous Ti by Biomimetic Mineralization: Effective Infection Prevention and Excellent Osteoinduction

Materials ◽

10.3390/ma14040992 ◽

2021 ◽

Vol 14 (4) ◽

pp. 992

Author(s):

Song Chen ◽

Yuanli He ◽

Linna Zhong ◽

Wenjia Xie ◽

Yiyuan Xue ◽

...

Keyword(s):

Calcium Phosphate ◽

Photoelectron Spectroscopy ◽

Antibacterial Properties ◽

Biomimetic Mineralization ◽

Matrix Mineralization ◽

X Ray ◽

Porous Ti ◽

Potential Applications ◽

Modification Of Titanium

The surface modification of titanium (Ti) can enhance the osseointegration and antibacterial properties of implants. In this study, we modified porous Ti discs with calcium phosphate (CaP) and different concentrations of Lactoferrin (LF) by biomimetic mineralization and examined their antibacterial effects and osteogenic bioactivity. Firstly, scanning electron microscopy (SEM), the fluorescent tracing method, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and the releasing kinetics of LF were utilized to characterize the modified Ti surface. Then, the antibacterial properties against S. sanguis and S. aureus were investigated. Finally, in vitro cytological examination was performed, including evaluations of cell adhesion, cell differentiation, extracellular matrix mineralization, and cytotoxicity. The results showed that the porous Ti discs were successfully modified with CaP and LF, and that the LF-M group (200 μg/mL LF in simulated body fluid) could mildly release LF under control. Further, the LF-M group could effectively inhibit the adhesion and proliferation of S. sanguis and S. aureus and enhance the osteogenic differentiation in vitro with a good biocompatibility. Consequently, LF-M-modified Ti may have potential applications in the field of dental implants to promote osseointegration and prevent the occurrence of peri-implantitis.

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Yttrium Doped TiO2 Thin Film for Gas Sensing Application Prepared by Spin Coating Method

10.21203/rs.3.rs-106302/v1 ◽

2020 ◽

Author(s):

M Abdul Kaiyum ◽

Naim Ahmed ◽

Arif Alam ◽

M Shamimur Rahman

Keyword(s):

Thin Film ◽

Photoelectron Spectroscopy ◽

Gas Sensing ◽

Low Cost ◽

Pure Titanium ◽

X Ray ◽

Sensing Applications ◽

Coating Method ◽

Set Up ◽

Spin Coater

Abstract Yttrium (Y) doped and pure Titanium Di-oxide (TiO2) thin films were prepared by using spin coater. The coater was set up in laboratory with low cost investment. The films were calcined at 450 °C for 1 hour. For characterization, Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Analysis (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Atomic Force Microscopy (AFM) were carried out. LCR Bridge - GW Instek LCR-821 was used for gas sensing applications. XPS showed that the change of electronic structure due to Y doping. SEM and AFM analysis were carried out to determine the surface morphology of the films. Yttrium (Y) decreased the crystallite size of the films and increased the surface roughness and porosity value, which was very good for many sensing applications. Gas sensing property of the deposited films were improved by the incorporation of yttrium impurities and the sensing property improved almost two times than pure TiO2 thin film. Different researches have been done their research related to this topic but no one researchers provide a precise explanation of their results, authors of this research have tried to do that. Moreover the films were prepared by a simple spin coater to reduce the production cost also.

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Surface Characteristics and Cell Adhesion Behaviors of the Anodized Biomedical Stainless Steel

Applied Sciences ◽

10.3390/app10186275 ◽

2020 ◽

Vol 10 (18) ◽

pp. 6275

Author(s):

Heng-Jui Hsu ◽

Chia-Yu Wu ◽

Bai-Hung Huang ◽

Chi-Hsun Tsai ◽

Takashi Saito ◽

...

Keyword(s):

Electron Microscopy ◽

Cell Culture ◽

Stainless Steel ◽

Cell Adhesion ◽

Oxide Layer ◽

Photoelectron Spectroscopy ◽

X Ray ◽

In Vitro Cell Culture ◽

Cell Culture Assay

In this study, an electrochemical anodizing method was applied as surface modification of the 316L biomedical stainless steel (BSS). The surface properties, microstructural characteristics, and biocompatibility responses of the anodized 316L BSS specimens were elucidated through scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffractometry, transmission electron microscopy, and in vitro cell culture assay. Analytical results revealed that the oxide layer of dichromium trioxide (Cr2O3) was formed on the modified 316L BSS specimens after the different anodization modifications. Moreover, a dual porous (micro/nanoporous) topography can also be discovered on the surface of the modified 316L BSS specimens. The microstructure of the anodized oxide layer was composed of amorphous austenite phase and nano-Cr2O3. Furthermore, in vitro cell culture assay also demonstrated that the osteoblast-like cells (MG-63) on the anodized 316L BSS specimens were completely adhered and covered as compared with the unmodified 316L BSS specimen. As a result, the anodized 316L BSS with a dual porous (micro/nanoporous) oxide layer has great potential to induce cell adhesion and promote bone formation.

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Nanosheets of CuCo2O4 As a High-Performance Electrocatalyst in Urea Oxidation

Applied Sciences ◽

10.3390/app9040793 ◽

2019 ◽

Vol 9 (4) ◽

pp. 793 ◽

Cited By ~ 5

Author(s):

Camila Zequine ◽

Fangzhou Wang ◽

Xianglin Li ◽

Deepa Guragain ◽

S.R. Mishra ◽

...

Keyword(s):

Fuel Cells ◽

Photoelectron Spectroscopy ◽

High Performance ◽

Nickel Foam ◽

Low Cost ◽

Agricultural Waste ◽

Bifunctional Catalyst ◽

X Ray Diffraction ◽

X Ray ◽

Electroactive Material

The urea oxidation reaction (UOR) is a possible solution to solve the world’s energy crisis. Fuel cells have been used in the UOR to generate hydrogen with a lower potential compared to water splitting, decreasing the costs of energy production. Urea is abundantly present in agricultural waste and in industrial and human wastewater. Besides generating hydrogen, this reaction provides a pathway to eliminate urea, which is a hazard in the environment and to people’s health. In this study, nanosheets of CuCo2O4 grown on nickel foam were synthesized as an electrocatalyst for urea oxidation to generate hydrogen as a green fuel. The synthesized electrocatalyst was characterized using X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. The electroactivity of CuCo2O4 towards the oxidation of urea in alkaline solution was evaluated using electrochemical measurements. Nanosheets of CuCo2O4 grown on nickel foam required the potential of 1.36 V in 1 M KOH with 0.33 M urea to deliver a current density of 10 mA/cm2. The CuCo2O4 electrode was electrochemically stable for over 15 h of continuous measurements. The high catalytic activities for the hydrogen evolution reaction make the CuCo2O4 electrode a bifunctional catalyst and a promising electroactive material for hydrogen production. The two-electrode electrolyzer demanded a potential of 1.45 V, which was 260 mV less than that for the urea-free counterpart. Our study suggests that the CuCo2O4 electrode can be a promising material as an efficient UOR catalyst for fuel cells to generate hydrogen at a low cost.

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Gradient Chitosan Hydrogels Modified with Graphene Derivatives and Hydroxyapatite: Physiochemical Properties and Initial Cytocompatibility Evaluation

International Journal of Molecular Sciences ◽

10.3390/ijms21144888 ◽

2020 ◽

Vol 21 (14) ◽

pp. 4888

Author(s):

Karolina Kosowska ◽

Patrycja Domalik-Pyzik ◽

Małgorzata Sekuła-Stryjewska ◽

Sylwia Noga ◽

Joanna Jagiełło ◽

...

Keyword(s):

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Mechanical Analysis ◽

Biological Properties ◽

Human Umbilical Cord ◽

Tissue Engineering Scaffolds ◽

X Ray ◽

Chitosan Matrix ◽

Graphene Derivatives

In this study, we investigated preparation of gradient chitosan-matrix hydrogels through a novel freezing–gelling–thawing method. The influence of three types of graphene family materials (GFM), i.e., graphene oxide (GO), reduced graphene oxide (rGO), and poly(ethylene glycol) grafted graphene oxide (GO-PEG), as well as hydroxyapatite (HAp) on the physicochemical and biological properties of the composite hydrogels was examined in view of their potential applicability as tissue engineering scaffolds. The substrates and the hydrogel samples were thoroughly characterized by X-ray photoelectron spectroscopy, X-ray diffractometry, infrared spectroscopy, digital and scanning electron microscopy, rheological and mechanical analysis, in vitro chemical stability and bioactivity assays, as well as initial cytocompatibility evaluation with human umbilical cord Wharton’s jelly mesenchymal stem cells (hUC-MSCs). We followed the green-chemistry approach and avoided toxic cross-linking agents, using instead specific interactions of our polymer matrix with tannic acid, non-toxic physical cross-linker, and graphene derivatives. It was shown that the most promising are the gradient hydrogels modified with GO-PEG and HAp.

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