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

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
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.

Green Synthesis of Silver Nanoparticles with Exceptional Colloidal Stability and its Catalytic Activity Toward Nitrophenol Reduction

NANO ◽  
2016 ◽  
Vol 11 (04) ◽  
pp. 1650046 ◽  
Author(s):  
Manisha Sharma ◽  
Amit Mishra ◽  
Vinod Kumar ◽  
Soumen Basu
Keyword(s):  
Silver Nanoparticles ◽  
Catalytic Activity ◽  
Colloidal Stability ◽  
Ag Nps ◽  
Step Process ◽  
Synthesis Parameters ◽  
Salt Addition ◽  
Nitrophenol Reduction ◽  
Vis Spectroscopy ◽  
One Step

Silver nanoparticles (Ag NPs) were synthesized by one-step process in the presence of kollicoat as capping, reducing and stabilizing mediator. The synthesized NPs were characterized by using FTIR, TEM, DLS, XRD, EDS and UV-Vis spectroscopy. The resulting Ag NPs had an incomparable colloidal stability against the salt addition and change of pH. The effect of different synthesis parameters and the catalytic property of the NPs were examined.

Seed-mediated synthesis and PEG coating of gold nanoparticles for controlling morphology and sizes

MRS Advances ◽  
2020 ◽  
Vol 5 (63) ◽  
pp. 3353-3360
Author(s):  
Susana Helena Arellano Ramírez ◽  
Perla García Casillas ◽  
Christian Chapa González
Keyword(s):  
Gold Nanoparticles ◽  
Polyethylene Glycol ◽  
Room Temperature ◽  
Colloidal Stability ◽  
Infrared Spectrometry ◽  
Ammonium Bromide ◽  
Chloroauric Acid ◽  
Vis Spectroscopy ◽  
Seed Mediated ◽  
Peg Coating

AbstractA significant area of research is biomedical applications of nanoparticles which involves efforts to control the physicochemical properties through simple and scalable processes. Gold nanoparticles have received considerable attention due to their unique properties that they exhibit based on their morphology. Gold nanospheres (AuNSs) and nanorods (AuNRs) were prepared with a seed-mediated method followed of polyethylene glycol (PEG)-coating. The seeds were prepared with 0.1 M cetyltrimethyl-ammonium bromide (CTAB), 0.005 M chloroauric acid (HAuCl4), and 0.01 M sodium borohydride (NaBH4) solution. Gold nanoparticles with spherical morphology was achieved by growth by aggregation at room temperature, while to achieve the rod morphology 0.1 M silver nitrate (AgNO3) and 0.1 M ascorbic acid solution were added. The gold nanoparticles obtained by the seed-mediated synthesis have spherical or rod shapes, depending on the experimental conditions, and a uniform particle size. Surface functionalization was developed using polyethylene glycol. Morphology, and size distribution of AuNPs were evaluated by Field Emission Scanning Electron Microscopy. The average size of AuNSs, and AuNRs was 7.85nm and 7.96 x 31.47nm respectively. Fourier transform infrared spectrometry was performed to corroborate the presence of PEG in the AuNPs surface. Additionally, suspensions of AuNSs and AuNRs were evaluated by UV-Vis spectroscopy. Gold nanoparticles were stored for several days at room temperature and it was observed that the colloidal stability increased once gold nanoparticles were coated with PEG due to the shield formed in the surface of the NPs and the increase in size which were 9.65±1.90 nm of diameter for AuNSs and for AuNRs were 29.03±5.88 and 8.39±1.02 nm for length and transverse axis, respectively.

scholarly journals PEGylated Gold Nanoparticles with Interesting Plasmonic Properties Synthesized Using an Original, Rapid, and Easy-to-Implement Procedure

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Ștefan Nițică ◽  
Alin Iulian Moldovan ◽  
Valentin Toma ◽  
Cristian Silviu Moldovan ◽  
Ioana Berindan-Neagoe ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Synthesis Method ◽  
Average Diameter ◽  
Liquid Droplets ◽  
Sers Substrates ◽  
New Class ◽  
One Step ◽  
Short Synthesis ◽  
Spherical Gold Nanoparticles ◽  
Synthesis Procedure

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.

scholarly journals Chitosan, Polyethylene Glycol and Polyvinyl Alcohol Modified MgFe2O4 Ferrite Magnetic Nanoparticles in Doxorubicin Delivery: A Comparative Study In Vitro

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3893
Author(s):  
Deevak Ramnandan ◽  
Seipati Mokhosi ◽  
Aliscia Daniels ◽  
Moganavelli Singh
Keyword(s):  
Drug Delivery ◽  
Polyethylene Glycol ◽  
Magnetic Nanoparticles ◽  
Polyvinyl Alcohol ◽  
Cell Viability ◽  
Colloidal Stability ◽  
Breast Adenocarcinoma ◽  
Thermal Method ◽  
Dependent Manner ◽  
Functional Surface

Cancer-based magnetic theranostics has gained significant interest in recent years and can contribute as an influential archetype in the effective treatment of cancer. Owing to their excellent biocompatibility, minute sizes and reactive functional surface groups, magnetic nanoparticles (MNPs) are being explored as potential drug delivery systems. In this study, MgFe2O4 ferrite MNPs were evaluated for their potential to augment the delivery of the anticancer drug doxorubicin (DOX). These MNPs were successfully synthesized by the glycol-thermal method and functionalized with the polymers; chitosan (CHI), polyvinyl alcohol (PVA) and polyethylene glycol (PEG), respectively, as confirmed by Fourier transform infrared (FTIR) spectroscopy. X-ray diffraction (XRD) confirmed the formation of the single-phase cubic spinel structures while vibrating sample magnetometer (VSM) analysis confirmed the superparamagnetic properties of all MNPs. Transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA) revealed small, compact structures with good colloidal stability. CHI-MNPs had the highest DOX encapsulation (84.28%), with the PVA-MNPs recording the lowest encapsulation efficiency (59.49%). The 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) cytotoxicity assays conducted in the human embryonic kidney (HEK293), colorectal adenocarcinoma (Caco-2), and breast adenocarcinoma (SKBR-3) cell lines showed that all the drug-free polymerized MNPs promoted cell survival, while the DOX loaded MNPs significantly reduced cell viability in a dose-dependent manner. The DOX-CHI-MNPs possessed superior anticancer activity (<40% cell viability), with approximately 85.86% of the drug released after 72 h in a pH-responsive manner. These MNPs have shown good potential in enhancing drug delivery, thus warranting further optimizations and investigations.

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

2019 ◽  
Vol 9 (4) ◽  
pp. 676 ◽  
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.

A multi-coordinating polymer ligand optimized for the functionalization of metallic nanocrystals and nanorods

2016 ◽  
Vol 191 ◽  
pp. 481-494 ◽  
Author(s):  
Wentao Wang ◽  
Xin Ji ◽  
Hunter Burns ◽  
Hedi Mattoussi
Keyword(s):  
Gold Nanoparticles ◽  
Colloidal Stability ◽  
Protein Corona ◽  
Growth Media ◽  
Nucleophilic Addition Reaction ◽  
One Step ◽  
Nonspecific Interactions ◽  
Anchoring Groups ◽  
Polymer Ligand

We report the design and use of a multi-coordinating polymer ligand that is ideally suited for functionalizing gold nanoparticles and nanorods, and promoting their steric stabilization in buffer media. The ligand is prepared via a one-step nucleophilic addition reaction between poly(isobutylene-alt-maleic anhydride) and amine-modified anchoring groups and hydrophilic moieties. Surface functionalization of gold nanoparticles and nanorods with this polymer yields nanocrystals that exhibit excellent long-term colloidal stability over a broad range of conditions, including pH changes and in growth media, as verified using dynamic light scattering measurements combined with agarose gel electrophoresis. This polymer coating can also prevent the formation of protein corona. These features bode well for use in biological applications where small size, reduced nonspecific interactions and colloidal stability are highly desired. Furthermore, this design can be easily expanded to functionalize a variety of other inorganic nanocrystals.

Photochemical transformations of thiolated polyethylene glycol coatings on gold nanoparticles

2016 ◽  
Vol 3 (5) ◽  
pp. 1090-1102 ◽  
Author(s):  
Stacey M. Louie ◽  
Justin M. Gorham ◽  
Eric A. McGivney ◽  
Jingyu Liu ◽  
Kelvin B. Gregory ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Polyethylene Glycol ◽  
Gold Nanoparticle ◽  
Uv Irradiation ◽  
Colloidal Stability ◽  
Chain Scission ◽  
Photochemical Reactions ◽  
Surface Coatings ◽  
Photochemical Transformations ◽  
Thiolated Polyethylene Glycol

Photochemical reactions can cause significant transformations of manufactured nanomaterials and their surface coatings in sunlit environments. In this study, loss of thiolated polyethylene glycol from gold nanoparticle surfaces by chain scission was observed under UV irradiation and resulted in diminished colloidal stability.

scholarly journals Gold Nanoparticles Endowed with Low-Temperature Colloidal Stability by Cyclic Polyethylene Glycol in Ethanol

Soft Matter ◽  
2021 ◽  
Author(s):  
M. Ali Aboudzadeh ◽  
Joscha Kruse ◽  
Maria Sanromán-Iglesias ◽  
Daniele Cangialosi ◽  
Ángel Alegría ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Polyethylene Glycol ◽  
Low Temperature ◽  
Thermal Behavior ◽  
Metal Nanoparticles ◽  
Polymer Brushes ◽  
Colloidal Stability ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Upper Critical Solution Temperature

The colloidal stability of metal nanoparticles is tremendously dependent on the thermal behavior of polymer brushes. Neat polyethylene glycol (PEG) presents an unconventional upper critical solution temperature in ethanol, where...

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