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The dynamic development of nanotechnology has enabled the development of innovative and novel techniques for the production and use of nanomaterials. One of them is the use of nanocapsules based on biodegradable biopolymer composites. Closing compounds with antimicrobial activity inside the nanocapsule cause the gradual release of biologically active substances into the environment, and the effect on pathogens is regular, prolonged and targeted. Known and used in medicine for years, propolis, thanks to the synergistic effect of active ingredients, has antimicrobial, anti-inflammatory and antiseptic properties. Biodegradable and flexible biofilms were obtained, the morphology of the composite was determined using scanning electron microscopy (SEM) and particle size was measured by the dynamic light scattering (DLS) method. Antimicrobial properties of biofoils were examined on commensal skin bacteria and pathogenic Candida isolates based on the growth inhibition zones. The research confirmed the presence of spherical nanocapsules with sizes in the nano/micrometric scale. The properties of the composites were characterized by infrared (IR) and ultraviolet (UV) spectroscopy. It has been proven that hyaluronic acid is a suitable matrix for the preparation of nanocapsules, as no significant interactions between hyaluronan and the tested compounds have been demonstrated. Color analysis and thermal properties, as well as the thickness and mechanical properties of the obtained films, were determined. Antimicrobial properties of the obtained nanocomposites were strong in relation to all analyzed bacterial and yeast strains isolated from various regions of the human body. These results suggest high potential applicability of the tested biofilms as effective materials for dressings to be applied on infected wounds. [ABSTRACT FROM AUTHOR]

The aim of this study was to use a simple, low-cost and environmentally friendly synthesis method to design nanocomposites. For this purpose, carbon nanostructures were used to reinforce the chitosan/alginate bond in order to improve the mechanical, solubility, water absorption and barrier (protection against UV radiation) properties of the chitosan/alginate structure. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), ultraviolet and visible light absorption spectroscopy (UV-VIS) and color analysis were utilized, and the thickness and mechanical properties of the obtained films were determined. The tests that were carried out showed an equal distribution of nanostructures in the composite material and the absence of chemical interactions between nanoparticles and polymers. It was also proven that the enrichment of the polysaccharide composite with graphene oxide and carbon nanotubes positively affected its absorption, mechanical capabilities and color. [ABSTRACT FROM AUTHOR]

In the era of growing plastic consumption, food waste by consumers and overproduction caused by economic reasons, the global goal is to decrease these phenomena. Biocomposite films investigated in the past years are creating a promising future toward ecological, intelligent and active packaging. Due to their unique properties, they can be used in many areas of our life and reduce the constantly increasing pollution of our planet. The aim of our study was to obtain innovative and flexible biopolymer films based on sodium alginate and chitosan, as well as to develop methods for generating nanocapsules with turmeric extract in them. Bionanocomposites were analyzed using UV-VIS, FTIR, photoluminescence spectroscopy and SEM microscopy, while contact angles, surface free energy, particle size (DLS) and zeta potential were determined. The mechanical and colorimetric properties of the produced films were investigated, and the water content, solubility and water absorption were determined. Microbiological tests were carried out to analyze the influence of the produced films on the development of microorganisms. The results of the performed analyses allowed us to confirm the presence of curcumin nano- and microcapsules in the alginate–chitosan composite. Moreover, studies have shown that the structure of polysaccharides does not change during capsule manufacturing. The film with the highest concentration of the capsules showed better parameters in tests of solubility, water content, degree of swelling and mechanical properties. The obtained properties of the developed films allow them to be used as active and intelligent packaging materials, or as their parts. [ABSTRACT FROM AUTHOR]

Nanotechnology is a dynamically developing field of science, due to the unique physical, chemical and biological properties of nanomaterials. Innovative structures using nanotechnology have found application in diverse fields: in agricultural and food industries, where they improve the quality and safety of food; in medical and biological sciences; cosmetology; and many other areas of our lives. In this article, a particular attention is focused on carbon nanomaterials, especially graphene, as well as carbon nanotubes and carbon quantum dots that have been successfully used in biotechnology, biomedicine and broadly defined environmental applications. Some properties of carbon nanomaterials prevent their direct use. One example is the difficulty in synthesizing graphene-based materials resulting from the tendency of graphene to aggregate. This results in a limitation of their use in certain fields. Therefore, in order to achieve a wider use and better availability of nanoparticles, they are introduced into matrices, most often polysaccharides with a high hydrophilicity. Such composites can compete with synthetic polymers. For this purpose, the carbon-based nanoparticles in polysaccharides matrices were characterized. The paper presents the progress of ground-breaking research in the field of designing innovative carbon-based nanomaterials, and applications of nanotechnology in diverse fields that are currently being developed is of high interest and shows great innovative potential. [ABSTRACT FROM AUTHOR]

The application of natural polymer matrices as medical device components or food packaging materials has gained a considerable popularity in recent years, this has occurred in response to the increasing plastic pollution hazard. Currently, constant progress is being made in designing two-component or three-component systems that combine natural materials which help to achieve a quality comparable to the purely synthetic counterparts. This study describes a green synthesis preparation of new bionanocomposites consisting of starch/chitosan/graphene oxide (GO), that possess improved biological activities; namely, good tolerability by human cells with concomitant antimicrobial activity. The structural and morphological properties of bionanocomposites were analyzed using the following techniques: dynamic light scattering, scanning and transmission electron microscopy, wettability and free surface energy determination, and Fourier transform infrared spectroscopy. The study confirmed the homogenous distribution of GO layers within the starch/chitosan matrix and their large particle size. The interactions among the components were stronger in thin films. Additionally, differential scanning calorimetry analysis, UV–vis spectroscopy, surface colour measurements, transparency, water content, solubility, and swelling degree of composites were also performed. The mechanical parameters, such as tensile strength and elongation at break (EAB) were measured in order to characterise the functional properties of obtained nanocomposites. The GO additive altered the thermal features of the composites and decreased their brightness. The EAB of composite was improved by the introduction of GO. Importantly, cell-based analyses revealed no toxic effect of the composites on HaCat keratinocytes and HepG2 hepatoma cells, although a pronounced bacteriostatic effect against various strains of pathogenic bacteria was observed. In conclusion, the starch/chitosan/GO nanocomposites reveal numerous useful physicochemical and biological features, which make them a promising alternative for purely synthetic materials. [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]