scholarly journals Effect of Reaction Time and Stability Properties of Gold Nanoparticles Synthesized by p-Aminobenzoic Acid and p-Aminosalicylic Acid

2020 ◽  
Vol 20 (2) ◽  
pp. 413
Author(s):  
Abdul Aji ◽  
Sri Juari Santosa ◽  
Eko Sri Kunarti
Keyword(s):  
Gold Nanoparticles ◽  
Reaction Time ◽  
Reducing Agent ◽  
Capping Agent ◽  
Aminobenzoic Acid ◽  
Aminosalicylic Acid ◽  
Reducing Ability ◽  
Red Color ◽  
The Stability ◽  
Gold Ion

In this work, we determined the influenced of the reaction time at the synthesis of gold nanoparticles (AuNPs) by p-aminosalicylic acid and p-aminobenzoic acid as reducing agent. Besides working as a reducing agent, the p-aminobenzoic acid and p-aminosalicylic acid also simultaneously played a role as a capping agent/stabilizing agent. Gold ion was first mixed with the pH adjusted p-aminobenzoic acid and p-aminosalicylic acid. The mixture then heated in boiling water at 86 °C. The formation of AuNPs was indicated by the appearance of red color and analyzed with UV/Vis spectrophotometry to evaluate their surface plasmon resonance (SPR) absorption in the wavelength range 400–800 nm. The reducing ability of the reducing agents was affected by its structure. Gold nanoparticles that were synthesized with p-aminosalicylic acid were more stable, faster and had a smaller size than its counterpart that is synthesized with p-aminobenzoic acid. The stability test over a periods 5 months showed that AuNPs were relatively stable.

scholarly journals Synthesis of Gold Nanoparticles Using p-Aminobenzoic Acid and p-Aminosalicylic Acid as Reducing Agent

2019 ◽  
Vol 19 (1) ◽  
pp. 68
Author(s):  
Abdul Aji ◽  
Eko Sri Kunarti ◽  
Sri Juari Santosa
Keyword(s):  
Gold Nanoparticles ◽  
Optimum Condition ◽  
Reducing Agents ◽  
Reducing Agent ◽  
Hydroxyl Group ◽  
Synthesis Process ◽  
Aminobenzoic Acid ◽  
Aminosalicylic Acid ◽  
Amino Groups ◽  
Transmission Electron

Synthesis of gold nanoparticles (AuNPs) by reduction of HAuCl4 with p-aminobenzoic acid and p-aminosalicylic acid as a reducing agent was investigated. This work was conducted in order to determine the optimum condition of AuNPs synthesis and examine the effect of the hydroxyl group in p-aminosalicylic acid towards the size, shape, and stability of the synthesized gold nanoparticles (AuNPs). The optimum condition of the gold nanoparticles synthesis was determined by UV/Vis spectrophotometer, the shape and size of gold nanoparticles were measured by Transmission Electron Microscope (TEM). The synthesis process was started by reacting HAuCl4 and the reducing agents in an aqueous solution at 86 ºC. The initial gold concentration, reducing agents concentration and pH were varied in order to obtain the optimum condition. In the optimum condition, the results showed that p-aminosalicylic acid containing both hydroxyl and amino groups performed higher reduction ability compared to p-aminobenzoic acid that only containing an amino group. Reducing agents which have a hydroxyl group (p-aminosalicylic acid) could produce AuNPs with a smaller concentration of HAuCl4 than p-aminobenzoic acid. Gold nanoparticles that were synthesized with p-aminosalicylic acid were more stable and had a smaller particle size compared to its counterpart that is synthesized with p-aminobenzoic acid.

scholarly journals DEVELOPMENT OF A METHOD FOR THE SYNTHESIS OF PLASMONIC GOLD NANOPARTICLES FOR A WIDE SPECTRAL REGION 520-720 nm

2017 ◽  
Vol 12 (5) ◽  
pp. 56-64
Author(s):  
I. I. Faskhutdinova ◽  
A. S. Mikhailov ◽  
B. I. Shapiro
Keyword(s):  
Gold Nanoparticles ◽  
Colloidal Stability ◽  
Wavelength Region ◽  
Reducing Agent ◽  
Plasmon Band ◽  
Long Wavelength ◽  
Aggregation Processes ◽  
Wide Range ◽  
Minimal Quantity ◽  
The Stability

A method of the synthesis of plasmon gold nanoparticles by the reduction of HAuCl4 with organic reductants, such as formalin, sodium citrate and hydroquinone has been studied. It is shown that, depending on the concentration of the reagents, the temperature of synthesis and the type of the reducing agent, the position of the maximum of the plasmon band varies in a wide range from 520 nm to 720 nm. A one-stage method using hydroquinone as a reducing agent for the synthesis of long-wave plasmonic gold nanoparticles that form agglomerates of smaller particles with a plasmon absorption band in the red region of the spectrum is proposed. Since the resulting sol is rapidly precipitated due to the aggregation processes, it has been found necessary to use stabilizers for its subsequent application. The influence of some stabilizers (gelatin, as well as surface-active substances polydimethyldiallylammonium chloride and cetyltrimethylammonium bromid) on the stability of the gold sol synthesized by the hydroquinone method has been studied. It is shown that all the types of investigated stabilizers even in a minimal quantity provide the colloidal stability of the sol for several hours. However, only a natural polymer, gelatin, stabilizes the sol so that the maximum absorption of the plasmon band remains in the long-wavelength region of the spectrum.

Synthesis of Silica-Coated Copper Nanoparticles and its Application to Red Color Glaze

2014 ◽  
Vol 970 ◽  
pp. 288-292 ◽  
Author(s):  
Shohei Shiomi ◽  
Eiichiro Matsubara ◽  
Hajime Taguchi ◽  
Shozo Hashida ◽  
Tadanori Yokoyama
Keyword(s):  
Deposition Rate ◽  
Sol Gel ◽  
Dissolution Behavior ◽  
Simple Liquid ◽  
Phase Reaction ◽  
Cu Nanoparticles ◽  
Reducing Ability ◽  
Red Color ◽  
Sol Gel Process ◽  
The Stability

A core-shell structure of Cu@SiO2, namely, silica-coated Cu nanoparticles, was synthesized by a simple liquid phase reaction. The reaction bath was optimized by evaluating the balance between the dissolution behavior of Cu nanoparticles and the deposition rate of SiO2shells for coating. The Cu nanoparticles were fabricated by an electroless deposition method. The deposition and dissolution behaviors of Cu were quantitatively evaluated by quartz crystal microbalance (QCM) measurements, combined with the reducing ability evaluated by the mixed potential measurements. SiO2shells were synthesized by a sol-gel process of tetraethyl orthosilicate (TEOS). The optimal responsiveness bath condition was also elucidated by the QCM measurement to evaluate the deposition rate of SiO2shells, which was much faster than the dissolution rate of Cu nanoparticles, indicating that the SiO2shells sufficiently coated the Cu nanoparticles. The stability of annealed Cu@SiO2nanoparticles was considerably increased and by using them, the red color glaze is achieved in easy and safe way.

Tyrosine-Selective Bioconjugation with Iminoxyl Radicals

2020 ◽  
Author(s):  
Katsuya Maruyama ◽  
Takashi Ishiyama ◽  
Yohei Seki ◽  
Kounosuke Oisaki ◽  
Motomu Kanai
Keyword(s):  
Reaction Time ◽  
Steric Hindrance ◽  
Room Temperature ◽  
Water Soluble ◽  
Light Irradiation ◽  
Sodium Ascorbate ◽  
Iminoxyl Radical ◽  
Short Reaction Time ◽  
Modified Peptides ◽  
The Stability

A novel Tyr-selective protein bioconjugation using the water-soluble persistent iminoxyl radical is described. The conjugation proceeded with high Tyr-selectivity and short reaction time under biocompatible conditions (room temperature in buffered media under air). The stability of the conjugates was tunable depending on the steric hindrance of iminoxyl. The presence of sodium ascorbate and/or light irradiation promoted traceless deconjugation, restoring the native Tyr structure. The method is applied to the synthesis of a protein-dye conjugate and further derivatization to azobenzene-modified peptides.

Intracellular mineralization of gold nanoparticles using gold ion-binding peptides with cell-penetrating ability

2021 ◽  
Author(s):  
Makoto Ozaki ◽  
Shuhei Yoshida ◽  
Takaaki Tsuruoka ◽  
Kenji Usui
Keyword(s):  
Gold Nanoparticles ◽  
Gold Nanostructures ◽  
Ion Binding ◽  
Cell Penetrating ◽  
Binding Peptides ◽  
Conventional Methods ◽  
Gold Ion

Our method can produce uniquely shaped gold nanostructures in lower HAuCl4 concentration than conventional methods by intracellular functions using peptide assembled structures as a template.

Simple and efficient: Gold nanoparticles from triphenylphosphane gold(I) carboxylates without addition of any further stabilizing and reducing agent

2011 ◽  
Vol 14 (5) ◽  
pp. 676-678 ◽  
Author(s):  
André Tuchscherer ◽  
Dieter Schaarschmidt ◽  
Steffen Schulze ◽  
Michael Hietschold ◽  
Heinrich Lang
Keyword(s):  
Gold Nanoparticles ◽  
Reducing Agent

An unsaturated metal site-promoted approach to construct strongly coupled noble metal/HNb3O8 nanosheets for efficient thermo/photo-catalytic reduction

Nanoscale ◽  
2017 ◽  
Vol 9 (38) ◽  
pp. 14654-14663 ◽  
Author(s):  
Lijuan Shen ◽  
Yuzhou Xia ◽  
Sen Lin ◽  
Shijing Liang ◽  
Ling Wu
Keyword(s):  
Noble Metal ◽  
Catalytic Reduction ◽  
Reducing Agent ◽  
Capping Agent ◽  
Strongly Coupled ◽  
Metal Site

A Nb4+-promoted approach has been developed to construct Pd/HNb3O8 without a reducing agent or a capping agent. The resulting composites function as efficient thermo/photo-catalysts.

Sign in / Sign up

Export Citation Format

Share Document