Role of Particle Size in Individual and Competitive Diffusion of Carboxylic Acid Derivatized Colloidal Gold Particles in Thermally Evaporated Fatty Amine Films

Abstract

We have recently shown that nanocomposites of colloidal particles in a fatty lipid matrix can be grown via a diffusion process controlled by selective electrostatic interactions. In this paper, a detailed investigation of the diffusion of carboxylic acid derivatized gold colloidal particles of different sizes into thermally evaporated octadecylamine films using quartz crystal microgravimetry (QCM), transmission electron microscopy, and UV−vis absorption and Fourier transform infrared (FTIR) spectroscopies is described. The QCM kinetics of gold cluster incorporation has been analyzed in terms of a one-dimensional Fickian-type diffusion model, and it is found that the cluster diffusivity increases with decreasing cluster size. The pH at which maximum cluster incorporation in the amine occurs was found to be dependent on the cluster size as well. FTIR spectroscopy of the fatty amine-gold particle composites indicated weak coupling of the clusters to the protonated amine groups as well as interesting cluster size dependent changes in the amine and methylene antisymmetric deformations as well as the methylene scissoring bands. In a competitive diffusion process of large and small gold particles, it was observed that bigger gold particles were preferentially incorporated into the amine matrix even though the cluster diffusivity is higher for the smaller gold particles.

Immobilization and biocatalytic activity of fungal protease on gold nanoparticle‐loaded zeolite microspheres

“…The surface plasmon resonance in the asprepared colloidal gold can be seen clearly at ca. 520 nm (curve 1) Patil et al, 1999). After stirring the colloidal gold solution with the zeolite for 12 h, there was loss in the intensity of surface plasmon resonance due to the decrease in concentration of gold nanoparticles in the aqueous solution (curve 2).…”

“…In a typical experiment, 100 mL of 1.25 Â 10 À4 M concentrated aqueous solution of chloroauric acid (HAuCl 4 ) was reduced by 0.01 g of sodium borohydride (NaBH 4 ) at room temperature to yield a ruby-red solution containing gold nanoparticles of 35 F 7 Å in diameter (Patil et al, 1999).…”

“…The decrease in intensity of the surface plasmon resonance in the aqueous colloidal gold solution (resonance at ca. 520 nm) Patil et al, 1999) arising due to binding of the gold nanoparticles to the zeolite was used to estimate the weight percentage loading of gold nanoparticles. The probable structure of the F-protnanogold-zeolite biomaterial is illustrated in Scheme 1.…”

Controlling the assembly of hydrophobized gold nanoparticles at the air–water interface by varying the interfacial tension

“…In a typical experiment, gold nanoparticles were synthesized by sodium borohydride reduction of 10-4 M aqueous solution of chloroauric acid, that results in a clear ruby red coloured gold nanoparticles solution of pH 9 with a particle size of 9 ± 15 nm [30].…”

Immunosensors Based on Layer‐by‐Layer Self‐Assembled Au Colloidal Electrode for the Electrochemical Detection of Antigen

“…100 mL aqueous solution containing 0.1 mM HAuCl 4 and 0.15 mM trisodium citrate was prepared (here, trisodium citrate acted as a capping agent and thus restricted the growth of Au) [23]. Next, 1 mL of a 0.05 M NaBH 4 solution was added at once into the gold solution under continuous stirring.…”