scholarly journals On the Synergism of Biogenic Gold Nanoparticles and Hydroxyaluminum Phthalocyanines in the Photoeradication of Staphylococcus aureus

Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7378
Author(s):  
Irena Maliszewska
Keyword(s):  
Staphylococcus Aureus ◽  
Gold Nanoparticles ◽  
Spherical Shape ◽  
Lethal Effect ◽  
Light Dose ◽  
Monodisperse Particles ◽  
Plasmon Band ◽  
First Time ◽  
Microbiological Society ◽  
Cell Free Filtrate

Due to the unusual properties of gold nanoparticles, these structures are widely used in medicine and biology. This paper describes for the first time the synthesis of colloidal gold nanoparticles by the cell-free filtrate obtained from the Coriolus versicolor biomass and the use of these biogenic nanostructures to increase the photosensitizing efficiency of di- (AlPcS2) and tetrasulfonated (AlPcS4) hydroxyaluminum phthalocyanines in antibacterial photodynamic therapy. The obtained monodisperse particles were extremely stable, and this remarkable stability was due to the presence of phosphoprotein as a capping agent. The studied gold nanoparticles had a spherical shape, were uniformly distributed, and were characterized by a single plasmon band at wavelength of 514–517 nm. Almost 60% of the gold particles were found to be in the range of 13 to 15 nm. In accordance with the regulations of the American Microbiological Society, indicating that any antimicrobial technique must kill at least 3 log CFU (99.9%) to be accepted as “antimicrobial”, this mortality of Staphylococcus aureus was shown to be achieved in the presence of AlPcS4 + AuNPs mixture and 4.8 J cm−2 light dose compared to AlPcS4 alone, which required a light dose of 24 J cm−2. The best effect of increasing the effectiveness of combating this pathogen was observed in the case of AlPcS2 + AuNPs as a photosensitizing mixture. The light dose of 24 J cm−2 caused a lethal effect of the studied coccus in the planktonic culture.

Synthesis of a silymarin-gold nanoparticle conjugate and analysis of its liver-protecting activity

2021 ◽  
Vol 22 ◽  
Author(s):  
Sergey Staroverov ◽  
Sergey Kozlov ◽  
Alexander Fomin ◽  
Konstantib Gabalov ◽  
Alexey Volkov ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Liver Disease ◽  
Carbon Tetrachloride ◽  
Glutathione Depletion ◽  
Laboratory Animals ◽  
Experimental Hepatitis ◽  
Acute Liver Disease ◽  
The Mean ◽  
Extent Of Damage ◽  
First Time

Background: The liver disease problem prompts investigators to search for new methods of liver treatment. Introduction: Silymarin (Sil) protects the liver by reducing the concentration of free radicals and the extent of damage to the cell membranes. A particularly interesting method to increase the bioavailability of Sil is to use synthesized gold nanoparticles (AuNPs) as reagents. The study considered whether it was possible to use the silymarin-AuNP conjugate as a potential liver-protecting drug. Method: AuNPs were conjugated to Sil and examine the liver-protecting activity of the conjugate. Experimental hepatitis and hepatocyte cytolysis after carbon tetrachloride actionwere used as a model system, and the experiments were conducted on laboratory animals. Result: For the first time, silymarin was conjugated to colloidal gold nanoparticles (AuNPs). Electron microscopy showed that the resultant preparations were monodisperse and that the mean conjugate diameter was 18–30 nm ± 0.5 nm (mean diameter of the native nanoparticles, 15 ± 0.5 nm). In experimental hepatitis in mice, conjugate administration interfered with glutathione depletion in hepatocytes in response to carbon tetrachloride was conducive to an increase in energy metabolism, and stimulated the monocyte–macrophage function of the liver. The results were confirmed by the high respiratory activity of the hepatocytes in cell culture. Conclusion: We conclude that the silymarin-AuNP conjugate holds promise as a liver-protecting agent in acute liver disease caused by carbon tetrachloride poisoning.

scholarly journals Phosphatidylserine-Gold Nanoparticles (PS-AuNP) Induce Prostate and Breast Cancer Cell Apoptosis

Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1094
Author(s):  
Allan Radaic ◽  
Nam E. Joo ◽  
Soo-Hwan Jeong ◽  
Seong-II Yoo ◽  
Nicholas Kotov ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Gold Nanoparticles ◽  
Biomedical Applications ◽  
Therapeutic Potential ◽  
Control Treatment ◽  
Track Record ◽  
Males And Females ◽  
Breast And Prostate Cancer ◽  
First Time

Prostate and breast cancer are the current leading causes of new cancer cases in males and females, respectively. Phosphatidylserine (PS) is an essential lipid that mediates macrophage efferocytosis and is dysregulated in tumors. Therefore, developing therapies that selectively restore PS may be a potential therapeutic approach for carcinogenesis. Among the nanomedicine strategies for delivering PS, biocompatible gold nanoparticles (AuNPs) have an extensive track record in biomedical applications. In this study, we synthesized biomimetic phosphatidylserine-caped gold nanoparticles (PS-AuNPs) and tested their anticancer potential in breast and prostate cancer cells in vitro. We found that both cell lines exhibited changes in cell morphology indicative of apoptosis. After evaluating for histone-associated DNA fragments, a hallmark of apoptosis, we found significant increases in DNA fragmentation upon PS-AuNP treatment compared to the control treatment. These findings demonstrate the use of phosphatidylserine coupled with gold nanoparticles as a potential treatment for prostate and breast cancer. To the best of our knowledge, this is the first time that a phosphatidylserine-capped AuNP has been examined for its therapeutic potential in cancer therapy.

scholarly journals Facile Green, Room-Temperature Synthesis of Gold Nanoparticles Using Combretum erythrophyllum Leaf Extract: Antibacterial and Cell Viability Studies against Normal and Cancerous Cells

Antibiotics ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 893
Author(s):  
Olufunto T. Fanoro ◽  
Sundararajan Parani ◽  
Rodney Maluleke ◽  
Thabang C. Lebepe ◽  
Jose R. Varghese ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Cell Viability ◽  
Leaf Extract ◽  
Room Temperature ◽  
Klebsiella Oxytoca ◽  
Cost Effective ◽  
Average Diameter ◽  
Antibacterial Activities ◽  
Inhibition Concentration ◽  
First Time

We herein report a facile, green, cost-effective, plant-mediated synthesis of gold nanoparticles (AuNPs) for the first time using Combretum erythrophyllum (CE) plant leaves. The synthesis was conducted at room temperature using CE leaf extract serving as a reducing and capping agent. The as-synthesized AuNPs were found to be crystalline, well dispersed, and spherical in shape with an average diameter of 13.20 nm and an excellent stability of over 60 days. The AuNPs showed broad-spectrum antibacterial activities against both pathogenic Gram-positive (Staphylococcus epidermidis (ATCC14990), Staphylococcus aureus (ATCC 25923), Mycobacterium smegmatis (MC 215)) and Gram-negative bacteria (Proteus mirabilis (ATCC 7002), Escherichia coli (ATCC 25922), Klebsiella pneumoniae (ATCC 13822), Klebsiella oxytoca (ATCC 8724)), with a minimum inhibition concentration of 62.5 µg/mL. In addition, the as-synthesized AuNPs were highly stable with exceptional cell viability towards normal cells (BHK- 21) and cancerous cancer cell lines (cervical and lung cancer).

Effect of Gold Nanoparticles Size on Detection of Methylphosphonic Acid Hydrolysis Product of Nerve Agent

2021 ◽  
Vol 25 (7) ◽  
pp. 1-7
Author(s):  
Fellyzra Elvya Pojol ◽  
Buong Woei Chieng ◽  
Keat Khim Ong ◽  
Rashid Jahwarhar Izuan Abd ◽  
Mohd Junaedy Osman ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Inverse Method ◽  
Direct Method ◽  
Hydrolysis Product ◽  
Spherical Shape ◽  
Methylphosphonic Acid ◽  
Visible Spectroscopy ◽  
Transmission Electron ◽  
Citrate Reduction ◽  
Chloride Trihydrate

Citrate reduction of gold (III) chloride trihydrate (HAuCl4) is commonly used method to synthesise citrate-capped gold nanoparticles (cit-AuNPs). In this study, the sequence of reagents addition was modified (“inverse” method) to synthesise smaller size of cit-AuNPs than the standard Turkevich method (“direct” method). Ultraviolet-visible spectroscopy (UV-vis) and field emission transmission electron microscopy (FETEM) confirmed the formation of cit-AuNPs. The cit-AuNPs synthesized using “inverse” method are smaller in size (14.0 ± 3.03 nm) with uniform spherical shape compared to “direct” method (23.5 ± 7.52 nm). Smaller particles size of cit-AuNPs provide higher efficiency and sensitivity for detection of methylphosphonic acid (MPA) via colorimetric incorporated with image processing with a linear range from 2.5 to 12.5 mM and a low detection limit of 6.28 mM at shorter detection period (24 to 30 s).

Abstract 394: ApoE3-containing High Density Lipoprotein Serves as a Multifunctional Platform for Delivery of Gold Nanoparticles for Hyperthermic Treatment

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Vasanthy Narayanaswami ◽  
Skylar T Chuang ◽  
Young-Seok Shon
Keyword(s):  
Gold Nanoparticles ◽  
Cellular Uptake ◽  
Effective Means ◽  
Density Lipoprotein ◽  
Aqueous Solubility ◽  
Soluble Form ◽  
Glioblastoma Cells ◽  
Plasmon Band ◽  
Cytotoxicity Studies ◽  
Multifunctional Platform

We have developed a novel HDL-based multifunctional platform for transport and delivery of highly hydrophobic gold nanoparticles (AuNP) bearing photothermic properties. We exploit the ability of apolipoprotein E3 (apoE3) to act as a high affinity ligand for the low-density lipoprotein receptor (LDLr) to gain entry into glioblastoma cells. The issue of poor aqueous solubility of AuNP was overcome by integrating them with phospholipids and apoE3, yielding reconstituted rHDL bearing 3, 10, or 10 nm AuNP. UV-Vis spectra of rHDL-AuNP indicated the presence of stable particles with surface plasmon band at ~530 nm, a signature feature of AuNP. Transmission electron microscopy (TEM) revealed discoidal geometry for rHDL with 3, 10 and 17 nm particles. Co-immunoprecipitation assay using a soluble form of the LDLr indicated robust binding of rHDL-AuNP to the receptor. Immunofluorescence analysis indicated that all 3 rHDL particles were internalized by glioblastoma cells, as revealed by the presence of punctate, peri-nuclear endocytic/lysosomal vesicles; this suggests cellular uptake of rHDL-AuNP by receptor-mediated endocytosis. Cellular uptake was further confirmed by TEM, in which aggregated AuNP were found in the endosomal-lysosomal compartments. Finally, cytotoxicity studies demonstrated that more than 50% of cells were viable with rHDL-AuNP treatment of up to 0.1 mg/ml for 24 h. The findings that apoE3: (i) acts as a detergent in solubilizing and dramatically improving the aqueous solubility of AuNP, and, (ii) facilitates cellular uptake of rHDL-AuNP by the LDLr pathway, are significant since they offer an effective means of delivering AuNP across the cell membrane. This is particularly relevant in tumor cells since they overexpress LDLr to meet the high demand for cholesterol that is required for rapid proliferation and membrane biogenesis.

Enhancement of efficiency in graphene/porous silicon solar cells by co-doping graphene with gold nanoparticles and bis(trifluoromethanesulfonyl)-amide

2017 ◽  
Vol 5 (35) ◽  
pp. 9005-9011 ◽  
Author(s):  
Ju Hwan Kim ◽  
Dong Hee Shin ◽  
Ha Seung Lee ◽  
Chan Wook Jang ◽  
Jong Min Kim ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Solar Cells ◽  
Porous Silicon ◽  
Au Nanoparticles ◽  
Silicon Solar Cells ◽  
Porous Si ◽  
Co Doping ◽  
Si Solar Cells ◽  
First Time

The co-doping of graphene with Au nanoparticles and bis(trifluoromethanesulfonyl)-amide is employed for the first time to enhance the performance of graphene/porous Si solar cells.

The Langmuir–Hinshelwood approach for kinetic evaluation of cucurbit[7]uril-capped gold nanoparticles in the reduction of the antimicrobial nitrofurantoin

2017 ◽  
Vol 19 (29) ◽  
pp. 18913-18923 ◽  
Author(s):  
E. Blanco ◽  
P. Atienzar ◽  
P. Hernández ◽  
C. Quintana
Keyword(s):  
Gold Nanoparticles ◽  
Nitro Compound ◽  
Kinetic Constants ◽  
Kinetic Evaluation ◽  
P Adsorption ◽  
First Time

Adsorption and surface kinetic constants of nitrofurantoin are calculated and compared with those of another nitro compound for the first time.

scholarly journals Effect of Solvent Refractive Index on the Surface Plasmon Resonance Nanoparticle Optical Absorption

2007 ◽  
Vol 7 (12) ◽  
pp. 4333-4338
Author(s):  
Gulay Ertas ◽  
Sefik Suzer
Keyword(s):  
Gold Nanoparticles ◽  
Refractive Index ◽  
Surface Plasmon ◽  
Surrounding Medium ◽  
Point Of View ◽  
Experimental Point ◽  
Absorption Bands ◽  
Plasmon Band ◽  
Silver And Gold Nanoparticles ◽  
Band Position

Optical properties of plasmon coupled silver and gold nanoparticles were studied as a function of the refractive index of the surrounding medium. Our studies confirmed that the effect of changes in the refractive index of the surrounding medium was more difficult to demonstrate from an experimental point of view, because of the very high susceptibility of nanoparticles to aggregate in aqueous and organic solvents. Whereas the position of the absorption bands of triiodide in these solvents shows a clear dependence on medium's refractive index, the surface plasmon band position of silver and gold nanoparticles do not exhibit the same dependence. This is attributed to a non-negligible interaction of these solvents with nanoparticle surfaces.

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