Gold-Citric Acid Colloidal Solution (Au, Purity: 99.9 %, Diameter: 150nm)

Typical Properties
CAS	7440-57-5
Catalog	ACM7440575-171
Molecular Weight	196.97 g/mol
Boiling Point	2808 °C (lit.)
Melting Point	1063 °C (lit.)
Flash Point	4 °C
Purity	99.9 %
Density	19.3 g/mL at 25 °C (lit.)
Appearance	Colloidal Suspension
Storage	2-8 °C
Color	Light orange-Dark red
Composition	Au
Concentration	2-3 wt.% (Available as per Customer requirement)
Diameter	150 nm
pH	3
Precautions for use	According to different application fields, mix with other material systems according to the recommended dosage, and use it after fully stirring. ·For industrial catalysts, recommended dosage: ≥20ppm; ·For beauty and health care products, recommended dosage: ≥3ppm.
Quality Level	200
Shipping	Ambient Temperature
Solvent	Water

Overview

Description

Gold nanoparticles dispersion is to disperse gold nanoparticles into a solvent to form a neutral solution with stable and uniform color. The color of the solution is not golden yellow but red. If other substances are added to form a condensed state, the solution turns blue. The solution has the same antibacterial properties as nano silver, and also has better safety for human consumption and contact. Gold nanoparticles have been widely used due to their unique physical and optical properties.

Features

·Evenly dispersed, small particles
·Good compatibility, easy to disperse, easy to add a variety of systems
·Good system stability, reliable performance, safety and environmental protection
·High specific surface area, high loading, easy surface functionalization

Application

·Electronics: Gold nanoparticles are used as conductors in everything from printing inks to electronic chips.
·Photodynamic therapy: Gold nanoparticles (including nanoshells and nanorods) in the near-infrared absorption band generate heat when excited by light at wavelengths of 700 to 800 nm. This feature enables the nanoparticles to destroy targeted tumors.
·Therapeutic agent delivery: Therapeutic agents can be coated on the surface of gold nanoparticles.
·Sensors: Gold nanoparticles are used in various sensors.
·Diagnosis: Detection of Biomarkers
·Probes, catalysis, fuel cells

Case Study

Improved Turkevich Synthesis Method and Scale Up Synthesis for Gold Nanoparticles

Florian Schulz, et al. Langmuir 2014, 30, 35, 10779-10784.

Turkevich synthesis is a classic gold nanoparticle (Au NPs) synthesis method that can reliably produce AuNPs with diameters from 5 to 150 nm. In this work, an improvement is proposed to replace citrate solution with citrate buffer as reducing agent or stabilizer to achieve higher tolerance to changes in precursor concentration.
Syntheses and Scale Up of AuNPs via Optimized Turkevich Method
· 800 ml 2.75 mM citrate buffer (sodium citrate (SC)/citric acid (CA): 75/25) in a 2000 ml beaker was heated to boiling point on a hot plate magnetic stirrer. The beaker can be covered to minimize evaporation of water but the synthesis is not affected by evaporation, so covering the beaker is not critical.
· Meanwhile, 200 ml precursor solution (HAuCl4·3H2O in water, c = 812.5 µM) was heated to 90-100 °C to avoid a temperature drop during subsequent mixing.
· The boiling time of the citrate buffer before precursor-addition was Δt = 15 min. The precursor solution was then quickly added under rapid stirring (800 rpm, stirring bar 40 x 8 mm, cylindrical) to the citrate buffer solution.
· After color-change of the solution it was heated to boiling for another 20 minutes before the hot plate was switched off to let the solution cool down to ~70 °C. The solution was then transferred into a glass bottle for storage.