Synthesis of Gold Nanoparticles Capped-Benzoic Acid Derivative Compounds (<i>o</i>-, <i>m</i>-, and <i>p</i>-Hydroxybenzoic Acid)

Abstract

The effect of a hydroxyl functional group of the benzoic acid derivative compound, i.e. o-hydroxybenzoic acid, m-hydroxybenzoic acid, and p-hydroxybenzoic acid on the synthesis of AuNPs has been studied. It was revealed that the pH, heating time, the concentration of capping agent and the concentration of Au3+ affected the formation of AuNPs. We discovered that o-hydroxybenzoic acid possessed the highest stability, yet it needed the highest concentration of Au3+ and faster reaction time than p-hydroxybenzoic acid and slower than m-hydroxybenzoic acid. The stability was verified by means of UV-Vis spectrophotometer, XRD, TEM, Particle Size Analyzer (PSA), and Zeta Potential with an aging time of more than 5 months. We concluded that o-hydroxybenzoic acid acquired the most effective redox reaction instead of m-hydroxybenzoic acid and p-hydroxybenzoic acid, resulted in the smaller sized and unaggregated AuNPs. We also confirmed that the hydroxyl group of o-hydroxybenzoic acid, m-hydroxybenzoic acid and p-hydroxybenzoic acid is the functional group responsible for the reduction of Au3+ to Au0.

Synthesis of Highly Stabilized AuNPs Using 3,5-Dinitrobenzoic Acid and Sodium Acetate as Capping Agents in an Aqueous Solution and their Bioactivity

“…A researcher has discovered that AuNPs used o-hydroxybenzoic acid possessed the highest stability than p, m-hydroxybenzoic acid-AuNPs also has the smaller sized and unaggregated AuNPs. They also confirmed that the hydroxyl group of o, m, p-hydroxybenzoic acid was responsible for the reduction of Au 3+ to Au 0 [8]. Additionally, sodium acetate has been used to modify the TiO2 particle shape from cube to ellipsoid in the alkaline solution and explained this change due to adsorption of acetate ions onto the surface of TiO2 particle [9].…”

“…They also found that the size of NPs was smaller, and the shape was more rounded when the pH was increased. In the same way, the basic condition makes the capping agent carry a negative charge (such as R-COO and R-O) and this capping agent binds and stabilizes the metal NPs [8]. From Figs.…”

Comparison of Blueberry and Dandelion Aqueous Extracts in the Synthesis of Gold and Silver Nanostructures, and Their Applications as Anti‐Pseudomonas aeruginosa Agent

“…In addition to these, individually these compounds could have promoted the development of trigonal, hexagonal and such other anisotropic AuNSs formation. For example, 3‐hydroxybenzoic acid was only present in the dandelion medium, and that can drive AuNSs have large trigonal and hexagonal morphologies [38] . Similarly, the dandelion extracts had very high amount of chlorogenic acid, which triggers anisotropic AuNSs formation (e. g. trigonal, hexagonal, flower etc.)…”

“…For example, 3-hydroxybenzoic acid was only present in the dandelion medium, and that can drive AuNSs have large trigonal and hexagonal morphologies. [38] Similarly, the dandelion extracts had very high amount of chlorogenic acid, which triggers anisotropic AuNSs formation (e. g. trigonal, hexagonal, flower etc.). [39,40] By comparing Table 2 and Table 3, excess amount of chlorogenic acid consumed during D-AgNSs and D-AuNS formation.…”

The Comparative of α- and β-Cyclodextrin as Stabilizing Agents on AuNPs and Application as Colorimetric Sensors for Fe³⁺ in Tap Water

“…o-HBA was chosen as the reducing agent of AuNPs due to its ability to convert Au 3+ to Au 0 with an optimization peak which is found in o-HBA at pH 12 [27]. α-and β-CDs were selected as a stabilizer because CDs are hollow compounds that have steric hindrance, so they can stabilize the nanoparticles.…”