Authors: E. Indrea, S. Dreve, I. Bratu, G. Mihailescu, L. Olenic, G. Tomoaia, A. Mocanu, O. Horovitz and M. Tomoaia-Cotisel
Affilation: Babes-Bolyai University of Cluj-Napoca, Romania
Pages: 461 - 464
Keywords: chitosan, globular protein, gold nanoparticles, nanocomposites, thin films
Our studies are focused on the structure of thin films of chitosan and of globular protein in both the absence and the presence of negatively charged gold nanoparticles. Deacetilated chitosan of high molecular weight and globular protein from aleurone cells of barley were used to prepare the thin organic films deposited on different solid substrates. Gold nanoparticles of 20 to 35 nm diameter range were prepared by reduction of gold complex salt with sodium citrate and then were embedded into chitosan and protein films. The structure of the obtained functional nanocomposite films and of their surface at atomic and molecular level is explored by FTIR, infrared reflection absorption spectroscopy (IRRAS), UV-Vis spectroscopy, scanning probe microscopy, electron microscopy and X-ray diffractions. The microstructural information obtained by single X-ray profile Fourier analysis of gold nanoparticles were the effective crystallite mean size, Deff(nm), the root mean square (rms) of the microstrains averaged along the [hkl] direction, <2>1/2hkl, and the staking fault probability. The morphology of nanocomposites was different than for the films cast from chitosan solution due to the presence of protein and gold nanoparticles. These materials have high stability and might have industrial and medical applications.