Gold nanoparticles stabilized by isonicotinic acid: Synthesis in water, dimethylformamide, dimethyl sulfoxide and characterization

• Published in: Russian journal of inorganic chemistry Vol. 60; no. 3; pp. 362 - 371
• Main Authors: Tatarchuk, V. V., Druzhinina, I. A., Sergievskaya, A. P., Zaikovskii, V. I., Sheludyakova, L. A., Plyusnin, P. E., Popovetskii, P. S.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.03.2015
• Subjects: Chemistry; Chemistry and Materials Science; Dimethyl sulfoxide; Gold; Inorganic Chemistry; Nanoparticles; Nuclei; Physical Chemistry of Solutions; Precipitates; Precipitation; Sedimentation; Sodium; Isonicotinic Acid; Surface Plasmon Resonance Band; Gold Nucleus; Oxygen Boron; Synchronous Thermal Analysis
• DOI: 10.1134/S0036023615030201
• ISSN: 0036-0236

Hydrophilic gold nanoparticles stabilized with isonicotinic acid (INA) were prepared by reduction of HAuCl 4 with sodium borohydride in the presence of INA in water, dimethylformamide, and dimethyl sulfoxide. The main condition for the preparation of good quality particles is to maintain reagent concentration ratio HAuCl 4 : INA : NaBH 4 = 1 : 2 : (5–10) at c Au ≤ 0.5 mM. Reaction products in water are mainly spherical primary particles with gold nuclei of 2–7 nm in diameter, those in dimethylformamide are secondary coalescent particles with nuclei of spheroid or slightly faceted shape 2–12 nm in diameter and larger elongated agglomerates from 15 to 100 nm long. Framework structures composed of chaotically agglomerated particles were obtained at HAuCl 4 : INA ratio larger than 1 : 2. By the example of precipitate of particles prepared in dimethylformamide and on the basis of data of chemical and thermal analysis, XPD, and IR spectroscopy, it was shown that the product contains gold, INA anion, acetone, water, sodium cations, and oxygen boron compounds. The particles obtained as precipitate or concentrate are well redispersible in water and polar solvents. The particles in colloid dispersions are in aggregated state and suffer gradual coagulation and sedimentation, which are not irreversible, and dispersed state can be restored by ultrasound treatment. The particles stabilized by INA may be of interest as initial product for preparation of nanomaterials for biomedical purposes.