Аннотация:New materials based on Au and Ag nanoparticles stabilized in a matrix of
microcrystalline and bacterial cellulose were prepared for medical applications. Au and
Ag nanoparticles were synthesized in i-PrOH by metal vapor synthesis (MVS) and
incorporated into the polysaccharide matrix using metal-containing organosol. The
MVS is an efficient route of purposeful synthesis of metallic nanoparticles and their
derived composites. Microcrystalline cellulose brand Avicel PH-101 with a
polymerization degree of 180 and an average particle size of 50 μm was used. Bacterial
cellulose films were synthesized by Gluconacetobacter hansenii producer strain. The
materials were characterized by transmission and scanning electron microscopy (TEM,
SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction, Fourier-transform
infrared spectroscopy and thermogravimetric analysis (TGA). TEM shows that Au and
Ag particles with average sizes of 10.2 and 17 nm, respectively, are on the surface of
microcrystalline cellulose powder. The valence states of Au and Ag determined by XPS
are Au0 and Ag0. In accordance with the TGA data, the introduction of Au and Ag
nanoparticles into microcrystalline cellulose has practically no effect on the thermal
stability of the polymers. SEM shows that the bacterial cellulose films containing metal
nanoparticles consist of filament fibers with different diameters, of which micro- and
macrofibrils with a diameter of 15-20 and 50-100 nm, respectively, were formed. The
metal nanoparticles have a wide size distribution. The bacterial cellulose nanocomposite
is a gradient material in which the metal concentration decreases from the surface to the
middle of the film.