Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Colloidal precipitates

Colloidal precipitates

The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...

The Colloidal State

The Colloidal State

The formation of a colloidal system is exemplified by an aqueous solution containing Cl− ions is introduced to another containing Ag+ ions, resulting in the precipitation of solid AgCl as extremely tiny crystals. Instead of settling out as a filterable precipitate, these crystals remain suspended in the liquid, showcasing a colloidal system.A colloidal system involves colloidal particles within the approximate range of 1 to 1000 nm in at least one dimension, dispersed in a medium called the...

Colloids

Colloids

Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles that are visible to the naked eye or can be seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. On the other hand, a solution is a homogeneous mixture in which no settling occurs and in which the dissolved...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Photoelectrochemical Hydrogen Peroxide Production via Simultaneous Reduction and Oxidation Processes.

Chemistry (Weinheim an der Bergstrasse, Germany)·2026

Same author

Photocatalytic hydrogen peroxide production toward quantum yields exceeding 100.

Chemical communications (Cambridge, England)·2025

Same author

Photocatalytic hydrogen peroxide production with an external quantum yield of almost 500.

Chemical science·2025

Same author

Site-Selective and High-Density Gold Nanoparticle Photodeposition on the Edges of ZnO Nanowires.

The journal of physical chemistry letters·2025

Same author

Metal oxide plating for maximizing the performance of ruthenium(IV) oxide-catalyzed electrochemical oxygen evolution reaction.

Nanoscale·2024

Same author

Efficient plasmonic water splitting by heteroepitaxial junction-induced faceting of gold nanoparticles on an anatase titanium(IV) oxide nanoplate array electrode.

Nanoscale·2024

Search research articles

Related Experiment Video

Updated: May 30, 2026

Gold Nanoparticle Synthesis

Gold Nanoparticle Synthesis

Published on: July 10, 2021

Dense aqueous colloidal gold nanoparticles prepared from highly concentrated precursor solution.

Tetsuro Soejima¹, Seisaku Oshiro, Yasuji Nakatsuji

¹Department of Applied Chemistry, Kinki University, 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan. soejima@apch.kindai.ac.jp

Journal of Colloid and Interface Science

|August 2, 2011

Summary

Researchers developed a rapid method to create stable gold and silver nanoparticle powders using casein proteins. These powders easily re-disperse into dense colloidal solutions, offering a scalable approach for nanoparticle synthesis.

More Related Videos

Synthesis of Functionalized 10-nm Polymer-coated Gold Particles for Endothelium Targeting and Drug Delivery

Synthesis of Functionalized 10-nm Polymer-coated Gold Particles for Endothelium Targeting and Drug Delivery

Published on: January 15, 2018

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Published on: March 2, 2016

Related Experiment Videos

Last Updated: May 30, 2026

Gold Nanoparticle Synthesis

Gold Nanoparticle Synthesis

Published on: July 10, 2021

Synthesis of Functionalized 10-nm Polymer-coated Gold Particles for Endothelium Targeting and Drug Delivery

Synthesis of Functionalized 10-nm Polymer-coated Gold Particles for Endothelium Targeting and Drug Delivery

Published on: January 15, 2018

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Published on: March 2, 2016

Area of Science:

Nanotechnology
Materials Science
Biochemistry

Background:

Gold nanoparticles (AuNPs) are crucial in various applications.
Efficient synthesis of stable, concentrated nanoparticle solutions remains a challenge.

Purpose of the Study:

To develop a rapid, one-pot synthesis for concentrated gold and silver nanoparticle powders.
To utilize casein proteins for stabilizing metal nanoparticles.
To achieve high re-dispersion of nanoparticle powders into stable colloidal solutions.

Main Methods:

Fabrication of gold nanoparticles via reduction of high-concentration Au(III) ions with casein.
Conversion of nanoparticles to powders through washing and vacuum drying.
Characterization using UV-vis spectroscopy, dynamic light scattering (DLS), and Fourier transform infrared (FT-IR) spectroscopy.
Development of casein-protected gold and silver nanoparticle synthesis using 3-amino-1-propanol.

Main Results:

Stable gold nanoparticle powders were produced without aggregation, re-dispersing into colloidal solutions.
Dynamic formation and disintegration of casein-Au(III) ion-nanoparticle assemblies were observed.
Casein protein conformational changes were confirmed due to interactions with Au(III) ions and gold nanoparticles.
Rapid synthesis yielded casein-protected gold and silver nanoparticle powders (below 10 nm) with high re-dispersion capabilities.
Dense colloidal gold (40 g L(-1)) and silver (22 g L(-1)) solutions were obtained.

Conclusions:

Casein proteins effectively stabilize gold and silver nanoparticles, enabling powder formation and re-dispersion.
A scalable, one-pot method for producing concentrated metal nanoparticle solutions was successfully established.
The developed method offers a promising route for the industrial application of metal nanoparticles.