scholarly journals Synthesis of Gold Nanoparticles Stabilized in Dextran Solution by Gamma Co-60 Ray Irradiation and Preparation of Gold Nanoparticles/Dextran Powder

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Phan Ha Nu Diem ◽  
Doan Thi Thu Thao ◽  
Dang Van Phu ◽  
Nguyen Ngoc Duy ◽  
Hoang Thi Dong Quy ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gold Nanoparticles ◽  
Spherical Shape ◽  
Powder Form ◽  
X Ray ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Influence Of Ph ◽  
Dextran Solution

Gold nanoparticles (AuNPs) in spherical shape with diameter of 6–35 nm stabilized by dextran were synthesized by γ-irradiation method. The AuNPs were characterized by UV-Vis spectroscopy and transmission electron microscopy. The influence of pH, Au3+ concentration, and dextran concentration on the size of AuNPs was investigated. Results indicated that the smallest AuNPs size (6 nm) and the largest AuNPs size (35 nm) were obtained for pH of 1 mM Au3+/1% dextran solution of 5.5 and 7.5, respectively. The smaller Au3+ concentration favored smaller size and conversely the smaller dextran concentration favored bigger size of AuNPs. AuNPs powders were prepared by spay drying, coagulation, and centrifugation and their sizes were also evaluated. The purity of prepared AuNPs powders was also examined by energy dispersive X-ray (EDX) analysis. Thus, the as-prepared AuNPs stabilized by biocompatible dextran in solution and/or in powder form can be potentially applied in biomedicine and pharmaceutics.

scholarly journals Effects of Different Surfactant Charges on the Formation of Gold Nanoparticles by the LASiS Method

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2937
Author(s):  
Muhammad Zulfajri ◽  
Wei-Jie Huang ◽  
Genin-Gary Huang ◽  
Hui-Fen Chen
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gold Nanoparticles ◽  
Laser System ◽  
Synthesis Process ◽  
Au Nps ◽  
Laser Fluences ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
532 Nm

The laser ablation synthesis in solution (LASiS) method has been widely utilized due to its significant prospects in laser microprocessing of nanomaterials. In this study, the LASiS method with the addition of different surfactant charges (cationic CTAB, nonionic TX-100, and anionic SDS) was used to produce Au NPs. An Nd:YAG laser system at 532 nm excitation with some synthetic parameters, including different laser fluences, ablation times, and surfactant concentrations was performed. The obtained Au NPs were characterized by UV-Vis spectroscopy, transmission electron microscopy, and zeta potential analyzer. The Au NPs exhibited the maximum absorption peak at around 520 nm for all samples. The color of Au NPs was changed from red to reddish by increasing the laser fluence. The surfactant charges also played different roles in the Au NPs’ growth during the synthesis process. The average sizes of Au NPs were found to be 8.5 nm, 5.5 nm, and 15.5 nm with the medium containing CTAB, TX-100, and SDS, respectively. Besides, the different surfactant charges induced different performances to protect Au NPs from agglomeration. Overall, the SDS and CTAB surfactants exhibited higher stability of the Au NPs compared to the Au NPs with TX-100 surfactant.

Aquatic Fern (AzollaSp.) Assisted Synthesis of Gold Nanoparticles

2016 ◽  
Vol 15 (01n02) ◽  
pp. 1650008 ◽  
Author(s):  
Anal K. Jha ◽  
K. Prasad
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gold Nanoparticles ◽  
Surface Plasmon Resonance ◽  
Au Nanoparticles ◽  
X Ray ◽  
Aquatic Fern ◽  
Transmission Electron ◽  
Anthraquinone Glycosides ◽  
Uv Visible

Aquatic pteridophyte (Azolla sp.) was taken to assess its potential to synthesize the metal (Au) nanoparticles. The synthesized particles were characterized using X-ray, UV-visible, scanning and transmission electron microscopy analyses. Nanoparticles almost spherical in shape having the sizes of 5–17[Formula: see text]nm are found. UV-visible study revealed the surface plasmon resonance at 538[Formula: see text]nm. Responsible phytochemicals for the transformation were principally phenolics, tannins, anthraquinone glycosides and sugars present abundantly in the plant thereby bestowing it adaptive prodigality. Also, the use of Azolla sp. for the synthesis of gold nanoparticles offers the benefit of eco-friendliness.

Synthesis of SrTiO3 Nanoparticles by a Simple Sonochemical Method

2012 ◽  
Vol 424-425 ◽  
pp. 949-952
Author(s):  
Yu Jiang Wang ◽  
Lin Lin Yang ◽  
Yong Gang Wang
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Spherical Shape ◽  
Sonochemical Method ◽  
X Ray ◽  
Transmission Electron ◽  
Ultrasonic Time ◽  
Pure Phase

SrTiO3 nanoparticles were successfully synthesized by a sonochemical method at room temperature. The as-prepared powders were characterized by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM), and exhibited a pure phase SrTiO3 with a perovskite structure about 20nm in size with uniform and nearly spherical shape. It is found that the size of the obtained nanoparticles increased with prolonging the ultrasonic time.

Effect of Nano-Sized Metal Colloids on Color Change of Photosensitive Glass by Using X-Ray Irradiation

2009 ◽  
Vol 620-622 ◽  
pp. 509-512
Author(s):  
Yong Kap Park ◽  
In Churl Cho ◽  
Y. Choi
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Color Change ◽  
Spherical Shape ◽  
Metal Colloids ◽  
X Ray ◽  
Photosensitive Glass ◽  
Transmission Electron ◽  
Ag Colloid ◽  
20 Nm

X-ray irradiation was applied to control the size of metal colloids in a silicate glass to make a high precise photosensitive glass containing K2O, Na2O, ZnO BaO, 0.01-0.05wt.% Au metal as sensitizer, <1.2wt.% Sb2O3 and SnO2 as thermal reducer. Colorimetry showed that X-ray irradiation effectively works to make the color of red system. Transmission electron microscopy revealed that the metal colloids were oxided and had uniform and spherical shape of 10-20 nm. Au colloid made various colors like pink after heating at 400°C, red at 500°C and dark-red at 600°C. Ag colloid made them like yellow-green at 400°C, yellow at 500°C and dark-brown, respectively.

Synthesis of Chitosan-Stabilized Gold Nanorod Using Tripolyphosphate

2013 ◽  
Vol 652-654 ◽  
pp. 250-253
Author(s):  
Hua Nan Guan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gold Nanoparticles ◽  
Chemical Synthesis ◽  
Gold Nanorods ◽  
Gold Nanorod ◽  
Gold Salt ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Seed Mediated

An improvement in the previously reported seed-mediated chemical synthesis of gold nanorods (GNRs) is reported. Gold nanoparticles were prepared by reducing gold salt with a polysaccharide, chitosan, in the presence of tripolyphosphate (TPP). The obtained gold nanoparticles were characterized with UV-vis spectroscopy and transmission electron microscopy. The study shows that TPP plays an important role in the formation of GNRs.

Intercalation of Gold Nanoparticles into Na-Montmorillonite

2013 ◽  
Vol 716 ◽  
pp. 360-363
Author(s):  
Peng Quan Yao ◽  
Lin Hua Zhu ◽  
Tian Si ◽  
Jin Yang
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gold Nanoparticles ◽  
Colloidal Particles ◽  
Fluorescence Analysis ◽  
Gold Colloid ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Polyallylamine Hydrochloride

Several type of gold precursors including pre-synthesized Au (en)2Cl3and gold colloid were tried to intercalate into the layer space of Na-Montmorillonite (Na-MMT). In the preparation, DDA and PAA were employed to cap the pre-synthesized gold colloidal particles and then intercalated into Na-MMT, and the Au (en)2Cl3was directly intercalated to Na-MMT through cation exchange. X-ray diffraction (XRD), fluorescence analysis (XRF) and transmission electron microscopy (TEM) were used to characterize the prepared samples. The results showed that the gold colloid modified by dodecylamine (DDA) and polyallylamine hydrochloride (PAA) respectively were successfully intercalated into the layer gallery of Na-MMT based on the mechanism of covalent capture. However, thermal treatment at 773K for 2h resulted in migration of gold nanoparticles from layer space to the out surface of the Na-MMT.

scholarly journals BIOSYNTHESIS AND CHARACTERIZATION OF SILVER NANOPARTICLES FROM MANGROVE BARK – RHIZOPHORA MUCRONATA EXTRACT

2020 ◽  
pp. 91-94
Author(s):  
AJI JOVITHA AT ◽  
DEIVASIGAMANI B
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Silver Nanoparticles ◽  
High Resolution ◽  
Room Temperature ◽  
Energy Dispersive ◽  
Rhizophora Mucronata ◽  
X Ray ◽  
Transmission Electron ◽  
Vis Spectroscopy

Objective: The present study attempted to synthesize AgNPs from mangrove bark Rhizophora mucronata and analyze characteristics. The synthesized AgNPs analyzed with UV–vis spectroscopy, high-resolution transmission electron microscopy (HRTEM), and energy-dispersive X-ray (EDX) for confirming the nanoparticles. Methods: The dried R. mucronata bark was powdered and kept in at 55°C for 15 min in a water bath and cooled at room temperature to get the extract. The R. mucronata bark extract was treated with silver nitrate and kept overnight in the dark environment which will turn the solution to dark brown color. The silver nanoparticles were characterized using UV–visible absorption at room temperature. Further characterization was also done with X-ray diffraction, high-resolution transmission electron microscope measurements, and DLS analysis. Results: The synthesized AgNPs were analyzed with various analytical methods that revealed the abundant presence of silver nanoparticles. The UV–vis spectroscopy analysis exposed the surface plasmon resonance peak of 422 nm. High-resolution transmission electron microscopy (HRTEM) analysis indicated the size ranging from 10 nm to 200 nm in diameter and a spherical shaped poly dispersal of the particles. The energy-dispersive X-ray (EDX) and DLS also confirmed the presence of silver atoms. Conclusion: Silver nanoparticles of Rhizophora mucronata bark revealed a well-defined structure and may be used in antimicrobial function in further researches.

scholarly journals SYNTHESIS AND CATALYTIC ACTIVITY OF BRANCHED GOLD NANOPARTICLES IN AQUEOUS MEDIUM

2018 ◽  
Vol 55 (5B) ◽  
pp. 227
Author(s):  
Phan Ha Nu Diem
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Transmission Electron Microscopy ◽  
Gold Nanoparticles ◽  
Kinetic Data ◽  
Gold Nanostructures ◽  
Simple Method ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Experimental Parameters

In this article, a simple method for the preparation of multi–branched gold nanoparticles from an aqueous solution of silver seeds, cetyl-trimethylammonium bromide (CTAB), HAuCl4, and Pluronic F–127 was described. It was found that morphologies and sizes of gold nanostructures (AuNPs) depended strongly on such experimental parameters as concentrations of Pluronic F–127 and Au3+. The products were characterized by transmission electron microscopy (TEM). Interestingly, the multi – branched AuNPs were found to serve as an effective catalyst for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of NaBH4. Kinetic data have been obtained from monitoring the concentrations of 4-NP and BH4‒ by UV‒vis spectroscopy.

scholarly journals Synthesis, Characterization, Anti-Cancer Analysis of Sr0.5Ba0.5DyxSmxFe8−2xO19 (0.00 ≤ x ≤ 1.0) Microsphere Nanocomposites

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 700
Author(s):  
Suhailah S. Al-Jameel ◽  
Munirah A. Almessiere ◽  
Firdos A. Khan ◽  
Nedaa Taskhandi ◽  
Yassine Slimani ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Cancer Cells ◽  
Spherical Shape ◽  
Hexagonal Structure ◽  
Dapi Staining ◽  
X Ray ◽  
Transmission Electron ◽  
Anti Cancer ◽  
Hct 116

There is enormous interest in combining two or more nanoparticles for various biomedical applications, especially in anti-cancer agent delivery. In this study, the microsphere nanoparticles were prepared (MSNPs) and their impact on cancer cells was examined. The MSNPs were prepared by using the hydrothermal method where strontium (Sr), barium (Ba), dysprosium (Dy), samarium (Sm), and iron oxide (Fe8−2xO19) were combined, and dysprosium (Dy) and samarium (Sm) was substituted with strontium (Sr) and barium (Ba), preparing Sr0.5Ba0.5DyxSmxFe8−2xO19 (0.00 ≤ x ≤ 1.0) MSNPs. The microspheres were characterized by X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) techniques. The diffraction pattern of nanohexaferrites (NHFs) reflected the signature peaks of the hexagonal structure. The XRD revealed a pure hexagonal structure without any undesired phase, which indicated the homogeneity of the products. The crystal size of the nanoparticles were in the range of 22 to 36 nm by Scherrer’s equation. The SEM of MSNPs showed a semi-spherical shape with a high degree of aggregation. TEM and HR-TEM images of MSNPs verified the spherical shape morphology and structure that approved an M-type hexaferrite formation. The anti-cancer activity was examined on HCT-116 (human colorectal carcinoma) and HeLa (cervical cancer cells) using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and post-48 h treatment of MSNPs caused a dose-dependent inhibition of HCT-116 and HeLa cell proliferation and growth. Conversely, no significant cytotoxic effect was observed on HEK-293 cells. The treatments of MSNPs also induced cancer cells DNA disintegration, as revealed by 4′,6-diamidino-2-phenylindole (DAPI) staining. Finally, these findings suggest that synthesized MSNPs possess potential inhibitory actions on cancerous cells without harming normal cells.

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