One-step synthesis of highly-biocompatible spherical gold nanoparticles using Artocarpus heterophyllus Lam. (jackfruit) fruit extract and its effect on pathogens

In this letter, we report a new, one-step, rapid, and easy-to-implement method for the synthesis of PEGylated gold nanoparticles (PEG-AuNPs) having a narrow size distribution and very interesting plasmonic properties. Unmodified polyethylene glycol molecules with a molecular weight of 1000 g/mole (PEG1000) have been employed as reducing and capping agents for the synthesis of spherical gold nanoparticles having an average diameter of 35 nm, within a few minutes. The novelty of the herein proposed synthesis method consists in the fact that the synthesis takes place inside of a sealed bottle flask containing aqueous solutions of PEG1000, tetrachloroauric(III) acid (HAuCl4), and NaOH, placed in the center of a microwave oven, capable to provide a very uniform temperature environment. It turned out that, during the very short synthesis procedure (2 minutes), PEG 1000 suffers an oxidative transformation in such a manner that its terminal alcohol groups (-CH2-OH) are transformed in carboxylate ones (-COO−). The as-synthesized PEG-AuNPs possess very interesting plasmonic properties allowing the detection of different molecules by means of SER spectroscopy performed either in liquid droplets or on solid spots. As a consequence of their unique plasmonic properties, the SER spectra acquired using this new class of nanoparticles on different molecules of interest (methylene blue, rhodamine 6G, doxorubicin, and 5-fluorouracil) are highly reproducible, making them ideal candidates for further use as SERS substrates.

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A Hybrid Nanoplatform of Graphene Oxide/Nanogold for Plasmonic Sensing and Cellular Applications at the Nanobiointerface

Applied Sciences ◽

10.3390/app9040676 ◽

2019 ◽

Vol 9 (4) ◽

pp. 676 ◽

Cited By ~ 8

Author(s):

Lorena Cucci ◽

Irina Naletova ◽

Giuseppe Consiglio ◽

Cristina Satriano

Keyword(s):

Gold Nanoparticles ◽

Graphene Oxide ◽

Microscopy Imaging ◽

Human Neuroblastoma ◽

Force Microscopy ◽

Atomic Force ◽

Plasmonic Sensing ◽

One Step ◽

Spherical Gold Nanoparticles ◽

Species Production

In this study, nanocomposites of spherical gold nanoparticles (AuNPs) and graphene oxide (GO) nanosheets were fabricated by a simple one-step reduction method. The characterisation by UV-visible spectroscopy of the plasmonic sensing properties pointed out to a strong interaction between graphene and metal nanoparticles in the hybrid GO-AuNP, as confirmed by nuclear magnetic resonance. Moreover, atomic force microscopy analyses demonstrated that the gold nanoparticles were mostly confined to the basal planes of the GO sheets. The response of the nanoassemblies at the biointerface with human neuroblastoma SH-SY5Y cell line was investigated in terms of nanotoxicity as well as of total and mitochondrial reactive oxygen species production. Confocal microscopy imaging of cellular internalization highlighted the promising potentialities of GO-AuNP nanoplatforms for theranostic (i.e., sensing/imaging + therapy) applications.

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Synthesis of Monodispersed Gold Nanoparticles with Exceptional Colloidal Stability with Grafted Polyethylene Glycol-g-polyvinyl Alcohol

Journal of Nanomaterials ◽

10.1155/2015/712359 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 14

Author(s):

Alaaldin M. Alkilany ◽

Alaa I. Bani Yaseen ◽

Mohammed H. Kailani

Keyword(s):

Gold Nanoparticles ◽

Polyethylene Glycol ◽

Polyvinyl Alcohol ◽

Colloidal Stability ◽

Kinetic Mechanism ◽

Grafted Copolymer ◽

Synthesis Parameters ◽

Salt Addition ◽

One Step ◽

Spherical Gold Nanoparticles

Herein, we report the synthesis of spherical gold nanoparticles with tunable core size (23–79 nm) in the presence of polyethylene glycol-g-polyvinyl alcohol (PEG-g-PVA) grafted copolymer as a reducing, capping, and stabilizing agent in a one-step protocol. The resulted PEG-g-PVA-capped gold nanoparticles are monodispersed with an exceptional colloidal stability against salt addition, repeated centrifugation, and extensive dialysis. The effect of various synthesis parameters and the kinetic/mechanism of the nanoparticle formation are discussed.

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Impact of Spherical Gold Nanoparticles from Phyllanthus emblica (Indian Gooseberry) Fruit Extract on the Photocatalytic Reduction of Methylene Blue Dye

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.22255 ◽

2019 ◽

Vol 31 (11) ◽

pp. 2613-2617 ◽

Cited By ~ 1

Author(s):

Ami Ansul Shah ◽

D. Jayalakshmi ◽

Belina Xavier

Keyword(s):

Methylene Blue ◽

Gold Nanoparticles ◽

Colour Change ◽

Scattering Method ◽

Light Illumination ◽

Phyllanthus Emblica ◽

Fruit Extract ◽

Tem Analysis ◽

Indian Gooseberry ◽

Spherical Gold Nanoparticles

In present study, gold nanoparticles are synthesized using the aqueous fruit extract of Phyllanthus emblica (Indian gooseberry) via the green synthesis route. The biomolecules such as phenols, ascorbic acid, flavanols and tannins play an important role in the reduction of the metal ions as investigated by FT-IR studies. The UV-visible spectroscopy studies confirm the surface plasmon resonance peaks in the range of 532-550 nm and is characteristic of the colour change from pale yellow to pinkish-purple. The TEM analysis exhibits the spherical gold nanoparticles in the range of 10-50 nm. The zeta potential observed value is found to be -9.92 mV indicating a good stability and highly dependent on the shape and the interparticle interaction of metal nanoparticles in the medium. The particle size obtained by the dynamic light scattering method is in agreement with the TEM analysis. Gold nanoparticles act as a potential catalyst under mercury light illumination and shows 92.4 % degradation of methylene blue from the contaminated water.

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Varied-shaped gold nanoparticles with nanogram killing efficiency as potential antimicrobial surface coatings for the medical devices

Scientific Reports ◽

10.1038/s41598-021-91847-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ewelina Piktel ◽

Łukasz Suprewicz ◽

Joanna Depciuch ◽

Sylwia Chmielewska ◽

Karol Skłodowski ◽

...

Keyword(s):

Gold Nanoparticles ◽

Medical Devices ◽

Multidrug Resistant ◽

Resistance Mechanisms ◽

Antimicrobial Spectrum ◽

Antimicrobial Coatings ◽

Low Toxicity ◽

Spherical Gold Nanoparticles ◽

Cost Efficient ◽

Bactericidal Efficiency

AbstractMedical device-associated infections are a serious medical threat, particularly for patients with impaired mobility and/or advanced age. Despite a variety of antimicrobial coatings for medical devices being explored to date, only a limited number have been introduced for clinical use. Research into new bactericidal agents with the ability to eradicate pathogens, limit biofilm formation, and exhibit satisfactory biocompatibility, is therefore necessary and urgent. In this study, a series of varied-morphology gold nanoparticles in shapes of rods, peanuts, stars and spherical-like, porous ones with potent antibacterial activity were synthesized and thoroughly tested against spectrum of Candida albicans, Pseudomonas aeruginosa, Staphylococcus aureus clinical strains, as well as spectrum of uropathogenic Escherichia coli isolates. The optimization of gold nanoparticles synthesis allowed to develop nanomaterials, which are proved to be significantly more potent against tested microbes compared with the gold nanoformulations reported to date. Notably, their antimicrobial spectrum includes strains with different drug resistance mechanisms. Facile and cost-efficient synthesis of gold nanoparticles, remarkable bactericidal efficiency at nanogram doses, and low toxicity, underline their potential for development as a new coatings, as indicated by the example of urological catheters. The presented research fills a gap in microbial studies of non-spherical gold nanoparticles for the development of antimicrobial coatings targeting multidrug-resistant pathogens responsible for device-associated nosocomial infections.

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