Synthesis of Gold Nanoparticles Using Mimosa tenuiflora Extract, Assessments of Cytotoxicity, Cellular Uptake, and Catalysis

Abstract Synthesis of gold nanoparticles (AuNPs) with plant extracts has gained great interest in the field of biomedicine due to its wide variety of health applications. In the present work, AuNPs were synthesized with Mimosa tenuiflora (Mt) bark extract at different metallic precursor concentrations. Mt extract was obtained by mixing the tree bark in ethanol-water. The antioxidant capacity of extract was evaluated using 2,2-diphenyl-1-picrylhydrazyl and total polyphenol assay. AuNPs were characterized by transmission electron microscopy, X-ray diffraction, UV-Vis and Fourier transform infrared spectroscopy, and X-ray photoelectron spectrometry for functional group determination onto their surface. AuMt (colloids formed by AuNPs and molecules of Mt) exhibit multiple shapes with sizes between 20 and 200 nm. AuMt were tested on methylene blue degradation in homogeneous catalysis adding sodium borohydride. The smallest NPs (AuMt1) have a degradation coefficient of 0.008/s and reach 50% degradation in 190s. Cell viability and cytotoxicity were evaluated in human umbilical vein endothelial cells (HUVEC), and a moderate cytotoxic effect at 24 and 48 h was found. However, toxicity does not behave in a dose-dependent manner. Cellular internalization of AuMt on HUVEC cells was analyzed by confocal laser scanning microscopy. For AuMt1, it can be observed that the material is dispersed into the cytoplasm, while in AuMt2, the material is concentrated in the nuclear periphery.

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Biogenic Gold Nanoparticles as Potent Antibacterial and Antibiofilm Nano-Antibiotics against Pseudomonas aeruginosa

Antibiotics ◽

10.3390/antibiotics9030100 ◽

2020 ◽

Vol 9 (3) ◽

pp. 100 ◽

Cited By ~ 5

Author(s):

Syed Ghazanfar Ali ◽

Mohammad Azam Ansari ◽

Mohammad A. Alzohairy ◽

Mohammad N. Alomary ◽

Sami AlYahya ◽

...

Keyword(s):

Electron Microscopy ◽

Pseudomonas Aeruginosa ◽

Gold Nanoparticles ◽

Laser Scanning ◽

Laser Scanning Microscopy ◽

Tinospora Cordifolia ◽

Confocal Laser ◽

X Ray Diffraction ◽

X Ray ◽

Average Size

Abstract: Plant-based synthesis of eco-friendly nanoparticles has widespread applications in many fields, including medicine. Biofilm—a shield for pathogenic microorganisms—once formed, is difficult to destroy with antibiotics, making the pathogen resistant. Here, we synthesized gold nanoparticles (AuNPs) using the stem of an Ayurvedic medicinal plant, Tinospora cordifolia, and studied the action of AuNPs against Pseudomonas aeruginosa PAO1 biofilm. The synthesized AuNPs were characterized by techniques such as ultraviolet-visible spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, energy-dispersive X-ray diffraction, X-ray diffraction, scanning electron microscopy (SEM), and transmission electron microscopy. The AuNPs were spherically shaped with an average size of 16.1 nm. Further, the subminimum inhibitory concentrations (MICs) of AuNPs (50, 100, and 150 µg/mL) greatly affected the biofilm-forming ability of P. aeruginosa, as observed by crystal violet assay and SEM, which showed a decrease in the number of biofilm-forming cells with increasing AuNP concentration. This was further justified by confocal laser scanning microscopy (CLSM), which showed irregularities in the structure of the biofilm at the sub-MIC of AuNPs. Further, the interaction of AuNPs with PAO1 at the highest sub-MIC (150 µg/mL) showed the internalization of the nanoparticles, probably affecting the tendency of PAO1 to colonize on the surface of the nanoparticles. This study suggests that green-synthesized AuNPs can be used as effective nano-antibiotics against biofilm-related infections caused by P. aeruginosa.

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Investigation of Spin Coating Cerium-Doped Hydroxyapatite Thin Films with Antifungal Properties

Coatings ◽

10.3390/coatings11040464 ◽

2021 ◽

Vol 11 (4) ◽

pp. 464

Author(s):

Simona Liliana Iconaru ◽

Mihai Valentin Predoi ◽

Patrick Chapon ◽

Sofia Gaiaschi ◽

Krzysztof Rokosz ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Spin Coating ◽

Laser Scanning ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

X Ray ◽

Antifungal Properties ◽

Scanning Electron

In this study, the cerium-doped hydroxyapatite (Ca10−xCex(PO4)6(OH)2 with xCe = 0.1, 10Ce-HAp) coatings obtained by the spin coating method were presented for the first time. The stability of the 10Ce-HAp suspension particles used in the preparation of coatings was evaluated by ultrasonic studies, transmission electron microscopy (TEM), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The surface morphology of the 10Ce-HAp coating was studied by SEM and atomic force microscopy (AFM) techniques. The obtained 10Ce-HAp coatings were uniform and without cracks or unevenness. Glow discharge optical emission spectroscopy (GDOES) and X-ray photoelectron spectroscopy (XPS) were used for the investigation of fine chemical depth profiling. The antifungal properties of the HAp and 10Ce-HAp suspensions and coatings were assessed using Candida albicans ATCC 10231 (C. albicans) fungal strain. The quantitative antifungal assays demonstrated that both 10Ce-HAp suspensions and coatings exhibited strong antifungal properties and that they successfully inhibited the development and adherence of C. albicans fungal cells for all the tested time intervals. The scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) visualization of the C. albicans fungal cells adherence to the 10Ce-HAp surface also demonstrated their strong inhibitory effects. In addition, the qualitative assays also suggested that the 10Ce-HAp coatings successfully stopped the biofilm formation.

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Influence of Salt Support Structures on Material Jetted Aluminum Parts

Materials ◽

10.3390/ma14154072 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4072

Author(s):

Benedikt Kirchebner ◽

Maximilian Ploetz ◽

Christoph Rehekampff ◽

Philipp Lechner ◽

Wolfram Volk

Keyword(s):

Molten Salts ◽

Laser Scanning ◽

Water Soluble ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Support Structures ◽

Micro Hardness ◽

X Ray ◽

Melting Temperatures ◽

Economic Support

Like most additive manufacturing processes for metals, material jetting processes require support structures in order to attain full 3D capability. The support structures have to be removed in subsequent operations, which increases costs and slows down the manufacturing process. One approach to this issue is the use of water-soluble support structures made from salts that allow a fast and economic support removal. In this paper, we analyze the influence of salt support structures on material jetted aluminum parts. The salt is applied in its molten state, and because molten salts are typically corrosive substances, it is important to investigate the interaction between support and build material. Other characteristic properties of salts are high melting temperatures and low thermal conductivity, which could potentially lead to remelting of already printed structures and might influence the microstructure of aluminum that is printed on top of the salt due to low cooling rates. Three different sample geometries have been examined using optical microscopy, confocal laser scanning microscopy, energy-dispersive X-ray spectroscopy and micro-hardness testing. The results indicate that there is no distinct influence on the process with respect to remelting, micro-hardness and chemical reactions. However, a larger dendrite arm spacing is observed in aluminum that is printed on salt.

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Vacuolar-type H+-ATPase regulates cytoplasmic pH in Toxoplasma gondii tachyzoites

Biochemical Journal ◽

10.1042/bj3300853 ◽

1998 ◽

Vol 330 (2) ◽

pp. 853-860 ◽

Cited By ~ 44

Author(s):

N. J. Silvia MORENO ◽

Li ZHONG ◽

Hong-Gang LU ◽

Wanderley DE SOUZA ◽

Marlene BENCHIMOL

Keyword(s):

Plasma Membrane ◽

Toxoplasma Gondii ◽

Laser Scanning ◽

Membrane Surface ◽

Surface Proteins ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Dependent Manner ◽

Cytoplasmic Ph ◽

Bafilomycin A1

Cytoplasmic pH (pHi) regulation was studied in Toxoplasma gondii tachyzoites by using the fluorescent dye 2ʹ,7ʹ-bis-(2-carboxyethyl)-5(6)-carboxyfluorescein. Their mean baseline pHi (7.07±0.06; n = 5) was not significantly affected in the absence of extracellular Na+, K+ or HCO3- but was significantly decreased in a dose-dependent manner by low concentrations of N,Nʹ-dicyclohexylcarbodi-imide (DCCD), N-ethylmaleimide (NEM) or bafilomycin A1. Bafilomycin A1 also inhibited the recovery of tachyzoite pHi after an acid load with sodium propionate. Similar concentrations of DCCD, NEM and bafilomycin A1 produced depolarization of the plasma membrane potential as measured with bis-(1,3-diethylthiobarbituric)trimethineoxonol (bisoxonol), and DCCD prevented the hyperpolarization that accompanies acid extrusion after the addition of propionate, in agreement with the electrogenic nature of this pump. Confocal laser scanning microscopy indicated that, in addition to being located in cytoplasmic vacuoles, the vacuolar (V)-H+-ATPase of T. gondii tachyzoites is also located in the plasma membrane. Surface localization of the V-H+-ATPase was confirmed by experiments using biotinylation of cell surface proteins and immunoprecipitation with antibodies against V-H+-ATPases. Taken together, the results are consistent with the presence of a functional V-H+-ATPase in the plasma membrane of these intracellular parasites and with an important role of this enzyme in the regulation of pHi homoeostasis in these cells.

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Bacterial lipopolysaccharides variably modulate in vitro biofilm formation of Candida species

Journal of Medical Microbiology ◽

10.1099/jmm.0.021832-0 ◽

2010 ◽

Vol 59 (10) ◽

pp. 1225-1234 ◽

Cited By ~ 51

Author(s):

H. M. H. N. Bandara ◽

O. L. T. Lam ◽

R. M. Watt ◽

L. J. Jin ◽

L. P. Samaranayake

Keyword(s):

Biofilm Formation ◽

Laser Scanning ◽

Significant Inhibition ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Dependent Manner ◽

Bacterial Lipopolysaccharides ◽

Species Specific ◽

Biofilm Development

The objective of this study was to evaluate the effect of the bacterial endotoxin LPS on Candida biofilm formation in vitro. The effect of the LPS of Pseudomonas aeruginosa, Klebsiella pneumoniae, Serratia marcescens and Salmonella typhimurium on six different species of Candida, comprising Candida albicans ATCC 90028, Candida glabrata ATCC 90030, Candida krusei ATCC 6258, Candida tropicalis ATCC 13803, Candida parapsilosis ATCC 22019 and Candida dubliniensis MYA 646, was studied using a standard biofilm assay. The metabolic activity of in vitro Candida biofilms treated with LPS at 90 min, 24 h and 48 h was quantified by XTT reduction assay. Viable biofilm-forming cells were qualitatively analysed using confocal laser scanning microscopy (CLSM), while scanning electron microscopy (SEM) was employed to visualize the biofilm structure. Initially, adhesion of C. albicans was significantly stimulated by Pseudomonas and Klebsiella LPS. A significant inhibition of Candida adhesion was noted for the following combinations: C. glabrata with Pseudomonas LPS, C. tropicalis with Serratia LPS, and C. glabrata, C. parapsilosis or C. dubliniensis with Salmonella LPS (P<0.05). After 24 h of incubation, a significant stimulation of initial colonization was noted for the following combinations: C. albicans/C. glabrata with Klebsiella LPS, C. glabrata/C. tropicalis/C. krusei with Salmonella LPS. In contrast, a significant inhibition of biofilm formation was observed in C. glabrata/C. dubliniensis/C. krusei with Pseudomonas LPS, C. krusei with Serratia LPS, C. dubliniensis with Klebsiella LPS and C. parapsilosis/C. dubliniensis /C. krusei with Salmonella LPS (P<0.05). On further incubation for 48 h, a significant enhancement of biofilm maturation was noted for the following combinations: C. glabrata/C. tropicalis with Serratia LPS, C. dubliniensis with Klebsiella LPS and C. glabrata with Salmonella LPS, and a significant retardation was noted for C. parapsilosis/C. dubliniensis/C. krusei with Pseudomonas LPS, C. tropicalis with Serratia LPS, C. glabrata/C. parapsilosis/C. dubliniensis with Klebsiella LPS and C. dubliniensis with Salmonella LPS (P<0.05). These findings were confirmed by SEM and CLSM analyses. In general, the inhibition of the biofilm development of LPS-treated Candida spp. was accompanied by a scanty architecture with a reduced numbers of cells compared with the profuse and densely colonized control biofilms. These data are indicative that bacterial LPSs modulate in vitro Candida biofilm formation in a species-specific and time-dependent manner. The clinical and the biological relevance of these findings have yet to be explored.

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Jiedu Sangen Decoction Inhibits Migration and Invasion of Colon Cancer SW480 Cells via Suppressing Epithelial Mesenchymal Transition

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2018/1495768 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Kai Zhang ◽

Tao Peng ◽

Qingying Yan ◽

Leitao Sun ◽

Haojun Miao ◽

...

Keyword(s):

Colon Cancer ◽

Laser Scanning ◽

Epithelial Mesenchymal Transition ◽

Laser Scanning Microscopy ◽

Migration And Invasion ◽

Confocal Laser ◽

Dependent Manner ◽

Mesenchymal Transition ◽

Matrigel Invasion ◽

Sw480 Cells

Jiedu Sangen Decoction (JSD), a traditional Chinese medicine (TCM) formula, has been widely used in China to treat gastrointestinal cancer, especially as an adjuvant therapy in colorectal cancer (CRC) patients. This study aimed to evaluate the efficacy of JSD and Jiedu Sangen aqueous extract (JSAE) in colon cancer cells and explored the underlining mechanisms by cytotoxicity assay, scratch assay, transwell migration assay, matrigel invasion assay, confocal laser scanning microscopy, and western blot analysis. We demonstrated that JSAE inhibited the growth of colon cancer SW480 cells in a dose-dependent manner and JSAE repressed cancer cell migration and invasion. Furthermore, epithelial mesenchymal transition (EMT) was reversed by JSAE via enhancing E-cadherin expression and attenuating protein levels of EMT promoting factors such as N-cadherin, Slug, and ZEB1. These findings provided the first experimental evidence confirming the efficacy of JSAE in repressing invasion and metastasis of CRC and paving a way for the broader use of JSD in clinic.

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Susceptibility of Mature Staphylococcus Biofilms to Chinese Herbal Decoction Sanhuang Jiedu: An In Vitro Study

BioMed Research International ◽

10.1155/2020/7473942 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Shaoe Zhang ◽

Xiao Wang ◽

Xiaotao Shi ◽

Honglue Tan ◽

Himanshu Garg

Keyword(s):

Laser Scanning ◽

Multidrug Resistant ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Control Group ◽

Antibiofilm Activity ◽

Dependent Manner ◽

Chinese Herbal ◽

Titanium Surfaces

Background. External socking and washing with the Chinese herbal Sanhuang Jiedu decoction (SHJD) can effectively control local limb infections with bone and implant exposure. However, the antibiofilm activities of this decoction in vitro have not yet been investigated. Therefore, the aim of this study was to examine the effects and characteristics of SHJD on the mature biofilms of multidrug-resistant staphylococci on a titanium surface. Methods. Biofilm-forming methicillin-resistant Staphylococcus epidermidis ATCC 35984 and S. aureus ATCC 43330, and non-biofilm-forming S. epidermidis ATCC 12228 were selected as the experimental strains. The mature biofilms were prepared on titanium surfaces. The five experimental groups were based on dilution concentrations (DC) of SHJD: the control group (biofilm incubated with 0.85% NaCl solution), the SHJD (DC:1/8) group (initial SHJD solution was diluted 1/8), the SHJD (DC:1/4) group, the SHJD (DC:1/2) group, and the SHJD (DC:1/1) group (initial SHJD solution). The effects of SHJD on the mature biofilms were observed with the bacterial spread plate method, crystal violet (CV) staining, scanning electron microscopy, and confocal laser scanning microscopy. Results. After culture in tryptic soy broth for 72 h, ATCC 43300 and ATCC 35984 produced mature biofilms and ATCC 12228 did not. The optical density value of ATCC 12228 was 0.11 ± 0.02 , significantly lower than that of ATCC 35984 ( 0.42 ± 0.05 ) or ATCC 43300 ( 0.41 ± 0.03 ) ( P < 0.05 ). The mature biofilms of ATCC 43300 and ATCC 35984 clearly disintegrated when incubated for 12–24 h with SHJD (DC:1/1) or SHJD (DC:1/2), showing only scattered bacterial adhesion. In the SHJD (DC:1/4) group, although many residual bacterial colonies still clustered together, presenting a biofilm structure, it was very looser than that in the SHJD (DC:1/8) group in which the biofilm was similar to that in the control group. For ATCC 12228, only colony adhesion was observed, and the number of colonies decreased as the concentration of SHJD or the culture period increased. The quantitative results for the bacterial spread plate and CV staining showed significant differences between the SHJD groups ( P < 0.05 ). Conclusion. SHJD has antibiofilm activity against multidrug-resistant Staphylococcus strains. It weakens or disrupts already-formed mature biofilms on titanium surfaces in a concentration- and incubation time-dependent manner.

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Contribution of Electron and Confocal Microscopy in the Study ofLeishmania–Macrophage Interactions

Microscopy and Microanalysis ◽

10.1017/s1431927604040851 ◽

2004 ◽

Vol 10 (5) ◽

pp. 656-661 ◽

Cited By ~ 11

Author(s):

Birgitta Rasmusson ◽

Albert Descoteaux

Keyword(s):

Confocal Microscopy ◽

Laser Scanning ◽

Protozoan Parasite ◽

Laser Scanning Microscopy ◽

Sand Fly ◽

Confocal Laser ◽

Mammalian Host ◽

Dependent Manner ◽

Phagosome Maturation ◽

Physical Barrier

Promastigotes of the protozoan parasite genusLeishmaniaare inoculated into a mammalian host when an infected sand fly takes a bloodmeal. Following their opsonization by complement, promastigotes are phagocytosed by macrophages. There, promastigotes differentiate into amastigotes, the form of the parasite that replicates in the phagolysosomal compartments of host macrophages. Although the mechanisms by which promastigotes survive the microbicidal consequence of phagocytosis remain, for the most part, to be elucidated, evidence indicates that glycoconjugates play a role in this process. One such glycoconjugate is lipophosphoglycan, an abundant promastigote surface glycolipid. Using quantitative electron and confocal laser scanning microscopy approaches, evidence was provided thatL. donovanipromastigotes inhibit phagolysosome biogenesis in a lipophosphoglycan-dependent manner. This inhibition correlates with an accumulation of periphagosomal F-actin, which may potentially form a physical barrier that preventsL. donovanipromastigote-containing phagosomes from interacting with endocytic vacuoles. Inhibition of phagosome maturation may constitute a strategy to provide an environment propitious to the promastigote-to-amastigote differentiation.

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Microcontact Printed Protein Micropatterns on Titanium Surface Characterized by Confocal Laser Scanning Microscopy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.487.730 ◽

2012 ◽

Vol 487 ◽

pp. 730-734 ◽

Cited By ~ 2

Author(s):

Chang Jiang Pan ◽

Yu Dong Nie ◽

Yun Xiao Dong

Keyword(s):

Laser Scanning ◽

Photoelectron Spectrum ◽

Titanium Surface ◽

Microcontact Printing ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Water Contact ◽

X Ray ◽

Replication Errors ◽

Titanium Surfaces

In this paper, two kinds of stamps (squares (a×a)) separated by spacing b, the values of a and b were varied from 2.5 µm to 50 µm), i.e. positive and negative stamps, were prepared. The stamps inked with the rhodamine-labeled bovine serum albumin (BSA) were then microcontacted with the aldehyde-functionalized titanium surfaces. Water contact angle and X-ray photoelectron spectrum (XPS) indicated that BSA can be covalently immobilized on aldehyde modified titanium surface by microcontact printing. The experimental results of CLSM showed that the patterns with resolution from 2.5 µm to 50 µm were obtained successfully. Both positive stamp and negative stamp were deformed when the value of a was less than or equal to 5 µm, which resulted in replication errors. Furthermore, the larger spacing (50 µm) resulted in stamp collapse when the value a of the positive stamp was less than or equal to 10 µm, leading to whole fluorescence on substrates.

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