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Silver nanoparticles possess valuable physical, chemical, and biological properties, rendering them widely applied as bioactive agents in the industry. Nonetheless, their influence on the natural environment and on living organisms remains unclear. Therefore, this study aims to investigate the impact of polymer composites containing silver nanoparticles on sperm cells. The nanosilver polymer composites were chemically synthesized, employing sodium alginate as the stabilizer. The reducing agents employed were solutions comprising sodium borohydride and xylose. The concentration of silver nanoparticles obtained after synthesis was 100 parts per million. The examined biological species were rabbit sperm cells. The impact of nanosilver on the sperm was assessed through the elucidation of the toxicity profile, comet test, and analysis of morphological characteristics of the animal cells. The results of the study demonstrate a twofold impact of polymer composites infused with silver nanoparticles on domestic rabbit sperm when obtained through chemical synthesis using two reducing agents (xylose and sodium borohydride) at a 10 ppm concentration. The comet test showed no harmful effect on the DNA integrity of rabbit sperm by the tested compounds. Twenty-four-hour exposure of rabbit spermatozoa to silver nanoparticles, obtained by reducing xylose and borohydride, induced significant secondary changes in the morphological structure of male reproductive cells. These findings indicate the potential reproductive toxicity of silver nanoparticles. [ABSTRACT FROM AUTHOR]

Nanometals constitute a rapidly growing area of research within nanotechnology. Nanosilver and nanogold exhibit significant antimicrobial, antifungal, antiviral, anti-inflammatory, anti-angiogenic, and anticancer properties. The size and shape of nanoparticles are critical for determining their antimicrobial activity. In this study, silver and gold nanoparticles were synthesized within a hyaluronic acid matrix utilizing distilled water and distilled water treated with low-pressure, low-temperature glow plasma in an environment of air and argon. Electron microscopy, UV-Vis and FTIR spectra, water, and mechanical measurements were conducted to investigate the properties of nanometallic composites. This study also examined their microbiological properties. This study demonstrated that the properties of the composites differed depending on the preparation conditions, encompassing physicochemical and microbiological properties. The application of plasma-treated water under both air and argon had a significant effect on the size and distribution of nanometals. Silver nanoparticles were obtained between the range of 5 to 25 nm, while gold nanoparticles varied between 10 to 35 nm. The results indicate that the conditions under which silver and gold nanoparticles are produced have a significant effect on their mechanical and antibacterial properties. [ABSTRACT FROM AUTHOR]

Nanotechnology plays an important role in many fields of science and the economy. A special example of nanostructures is silver nanoparticles (AgNPs) created following the principles of green chemistry, i.e., without the use of toxic reducing compounds. The common tomato (Solanum lycopersicum) is a popular vegetable whose germination and growth process are studied by using, e.g., in vitro cultures. The aim of the experiment was to evaluate the inhibitory effect of the biodegradable gels containing silver nanoparticles on the development of microbial infection and to evaluate their influence on the germination degree of Tomato (Solanum lycopersicum) seeds in in vitro plant cultures. Based on macroscopic and microscopic observations, all experimental samples showed the presence of Gram-positive bacilli as well as mould fungi of the genus Rhizopus, Alternaria and Aspergillus. The study showed that the biocomponents containing silver nanoparticles obtained by using xylose as a reducing agent limit the development of microbial infection and stimulate the germination rate of tomato seeds. They could find their application as biodegradable raw materials in the production of modern disinfecting preparations for research in in vitro cultures. This study allowed to identify new research directions, especially to evaluate the metabolic regulation of seedlings treated with biodegradable silver nanoparticles. [ABSTRACT FROM AUTHOR]

Polymer nanocomposites containing nanometals became a subject of interest due to their bactericidal properties. Different polysaccharides have been used as matrices for nanosilver and nanogold synthesis. In this study, we present a novel, environmentally friendly method for the preparation of sodium alginate/nanosilver/graphene oxide (GOX) and sodium alginate/nanogold/graphene oxide GOX nanocomposites and their characteristics. The formation of approximately 10–20 nm ball-shaped Ag and Au nanoparticles was confirmed by UV–vis spectroscopy, scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectra. The incorporation of GOX sheets within the ALG matrix improved the thermal stability of the nanocomposites film, which was measured using the differential scanning calorimetry (DSC). We also estimated the molecular weights of polysaccharide chains of the matrix with the size exclusion chromatography coupled with multiangle laser light scattering and refractometric detectors (HPSEC-MALLS-RI). The composites were more prone to enzymatic hydrolysis. The strongest bacteriostatic activity was observed for the sample containing nanosilver. [ABSTRACT FROM AUTHOR]

The rapid progress of nanotechnology triggers the development of nanomedicine. As the antimicrobial properties of nanosilver are well known, there is a huge interest in the synthesis of silver nanoparticles using environmentally-friendly methods. In this study we described the functional (rheological, mechanical, surface, structural) properties of gels and foils containing silver nanoparticles embedded in hyaluronan and hyaluronan-lecithin matrix prepared using the methods of green chemistry. The study showed that the addition of silver strengthened the structure of Hyal foil, but reduced the stretch of the sample and that lecithin weakened the mechanical properties of the composites. Also, the presence of nanosilver made the studied foils partially hydrophilic, while these with lecithin were more hydrophobic. The results of the study are significant for the adaptation of the investigated materials to their potential applications. • Functional and structural properties of Hyal/Ag and Hyal-L/Ag composites. • Hyal-L/Ag and Hyal/Ag samples were more pseudoplastic than pure Hyal. • Silver strengthened the structure of Hyal foil and made it partially hydrophilic. • Lecithin weakened the mechanical properties of the composite. [ABSTRACT FROM AUTHOR]

A facile and environmentally friendly method of the preparation of silver nanoparticles embedded in hyaluronan (Hyal/Ag) and hyaluronan-lecithin (Hyal-L/Ag) matrix was developed. Thin, elastic foils were prepared from gels by an in situ synthesis of Ag in an aqueous solution of sodium hyaluronate (Hyal), using aq. d -(+)-xylose solution as a reducing agent. The gels were applied to a clean, smooth, defatted Teflon surface and left for drying in the air. The dry foils were stored in a closed container. UV–vis spectroscopy, transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectra confirmed formation of about 10 nm ball-shaped Ag nanoparticles situated within the polysaccharide template. Thermal properties of the composites were characterized involving differential scanning calorimetry (DSC) and thermogravimetric (TGA) analyses, whereas molecular weights of polysaccharide chains of the matrix were estimated with the size exclusion chromatography coupled with multiangle laser light scattering and refractometric detectors (HPSEC-MALLS-RI). An increase in the molecular weight of the hyaluronate after generation of Ag nanoparticles was observed. The foils showed specific properties. The study confirmed that silver nanoparticles can be successfully prepared with environmentally friendly method, using hyaluronan as a stabilizing template. Hyaluronan and hyaluronan-lecithin matrices provide nanocrystals uniform in size and shape. The composites demonstrated a bacteriostatic activity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Preparation of silver and gold nanoparticles embedded in dialdehyde starch matrix. [•] Dialdehyde starch (DAS) acting as stabilizing template and reducing agent. [•] The nanocomposite films were characterized by FTIR, SEM, TEM, DSC and HPSEC-MALLS-RI. [•] Polymerization and/or crosslinking of polysaccharide chains observed during formation of nano Ag and nano Au structures. [ABSTRACT FROM AUTHOR]

Frequent occurrence of microbial resistance to biocides makes it necessary to find alternative antimicrobial substances for modern veterinary medicine. The aim of this study was to obtain biodegradable silver nanoparticle-containing (AgNPs) foils synthesized using non-toxic chemicals and evaluation of their activity against bacterial pathogens isolated from oral cavities of cats, dogs and horses. Silver nanoparticle foils were synthesized using sodium alginate, and glucose, maltose and xylose were used as reducing agents. The sizes of AgNPs differed depending on the reducing agent used (xylose < maltose < glucose). Foil without silver nanoparticles was used as control. Bacterial strains were isolated from cats, dogs and horses by swabbing their oral cavities. Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli and extended-spectrum beta-lactamase (ESBL) producing E. coli were isolated on selective chromogenic microbiological media. The bactericidal effect of AgNPs foils obtained using non-toxic chemical compounds against E. coli, ESBL, S. aureus and MRSA isolated from oral cavities of selected animals was confirmed in this study. No statistically significant differences were observed between the foils obtained with different reducing agents. Therefore, all types of examined foils proved to be effective against the isolated bacteria. [ABSTRACT FROM AUTHOR]

For the last years scientific community has witnessed a rapid development of novel types of biomaterials, which properties made them applicable in numerous fields of medicine. Although nanosilver, well-known for its antimicrobial, anti-angiogenic, anti-inflammatory and anticancer activities, as well as hyaluronic acid, a natural polysaccharide playing a vital role in the modulation of tissue repair, signal transduction, angiogenesis, cell motility and cancer metastasis, are both thoroughly described in the literature, their complexes are still a novel topic. In this review we introduce the most recent research about the synthesis, properties, and potential applications of HA-nanosilver composites. We also make an attempt to explain the variety of mechanisms involved in their action. Finally, we present biocompatible and biodegradable complexes with bactericidal activity and low cytotoxicity, which properties suggest their suitability for the prophylaxis and therapy of chronic wounds, as well as analgetic therapies, anticancer strategies and the detection of chemical substances and malignant cells. Cited studies reveal that the usage of hyaluronic acid-silver nanocomposites appears to be efficient and safe in clinical practice. [ABSTRACT FROM AUTHOR]

Natural polysaccharides, including hyaluronic acid, find a wide range of applications in biomedical sciences. There is a growing interest in nanocomposites containing hyaluronic acid and nanoparticles such as nanometals or graphene. In this study, we prepared foils of pure sodium hyaluronate and sodium hyaluronate containing nanosilver, graphene oxide, nanosilver/graphene oxide and characterized their properties. UV-vis spectroscopy and scanning electron microscopy (SEM) confirmed the formation of 10–20 nm silver nanoparticles. The structural changes were investigated using Fourier transforms infrared (FTIR) spectra and size exclusion chromatography. The obtained results suggest changes in molecular weights in the samples containing nanoparticles, which was highest in a sample containing nanosilver/graphene oxide. We also assessed the mechanical properties of the foils (thickness, tensile strength and elongation at break) and their wettability. The foils containing nanosilver and nanosilver/graphene oxide presented bacteriostatic activity against E. coli, Staphylococcus spp. and Bacillus spp., which was not observed in the control and sample containing graphene oxide. The composites containing graphene oxide and nanosilver/graphene oxide exhibited a cytotoxic effect on human melanoma WM266-4 cell lines (ATCC, Manassas, VA, USA). [ABSTRACT FROM AUTHOR]

There is a serious need to develop and test new biodegradable packaging which could at least partially replace petroleum-based materials. Therefore, the objective of this work was to examine the influence of the recently developed furcellaran nanocomposite film with silver nanoparticles (obtained by an in situ method) on the quality properties of two cheese varieties: a rennet-curd (gouda) and an acid-curd (quark) cheese. The water content, physicochemical properties, microbiological and organoleptic quality of cheese, and migration of silver nanoparticles were examined. Both the number of Lactococcus and total bacteria count did not differ during storage of gouda regardless of the packaging applied. The number of Lactococcus decreased in analogous quark samples. The use of the film slowed down and inhibited the growth of yeast in gouda and quark, respectively. An inhibitory effect of this film on mold count was also observed; however, only regarding gouda. The level of silver migration was found to be lower in quark than in gouda. The film improved the microbiological quality of cheeses during storage. Consequently, it is worth continuing research for the improvement of this film in order to enable its use in everyday life. [ABSTRACT FROM AUTHOR]

• Furcellaran nanocomposite films were prepared by solvent casting method. • Functional properties of FUR + AgNPs, FUR + GO and FUR + MWCNTs films were compared. • AgNPs were synthesized in situ within the FUR matrix. • Nanofillers influenced structural, physical and thermal properties of FUR films. • Antimicrobial and antifungal activity of FUR + AgNPs films were characterized. Graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) were added to furcellaran films (FUR). Silver nanoparticles (AgNPs) were prepared by reducing AgNO 3 using a FUR matrix as the stabilising agent. The structure and surface morphology of nanocomposite films were obtained using FTIR, SEM and XRD. The molecular weights of furcellaran chains were estimated using HPSEC-MALLS-RI. Characterisation of the films was undertaken to analyse their physical, mechanical and structural properties. SEM analysis revealed that GO, MWCNTs and AgNPs were evenly distributed throughout the FUR surface. FUR + AgNP films showed antimicrobial activity against bacteria and fungi. P. aeruginosa , E. faecalis and S. aureus were the most affected with effective growth inhibition using the disc diffusion method. In the study, the effect of nanofillers on the structural, thermal, mechanical and antimicrobial properties of furcellaran films as potential materials for food packaging is presented. [ABSTRACT FROM AUTHOR]