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The development of multifunctional dressing materials with beneficial properties for wound healing has become a recent focus of research. Many studies are being conducted to incorporate active substances into dressings to positively impact wound healing processes. Researchers have investigated various natural additives, including plant extracts and apiproducts such as royal jelly, to enhance the properties of dressings. In this study, polyvinylpyrrolidone (PVP)-based hydrogel dressings modified with royal jelly were developed and analyzed for their sorption ability, wettability, surface morphology, degradation, and mechanical properties. The results showed that the royal jelly and crosslinking agent content had an impact on the physicochemical properties of the hydrogels and their potential for use as innovative dressing materials. This study investigated the swelling behavior, surface morphology, and mechanical properties of hydrogel materials containing royal jelly. The majority of the tested materials showed a gradual increase in swelling ratio with time. The pH of the incubated fluids varied depending on the type of fluid used, with distilled water having the greatest decrease in pH due to the release of organic acids from the royal jelly. The hydrogel samples had a relatively homogeneous surface, and no dependence between composition and surface morphology was observed. Natural additives like royal jelly can modify the mechanical properties of hydrogels, increasing their elongation percentage while decreasing their tensile strength. These findings suggest possible future applications in various fields requiring high flexibility and elasticity.

Tamoxifen is a well-known active substance with anticancer activity. Currently, many investigations are performed on the development of carriers that provide its effective delivery. Particular attention is directed toward the formation of cyclodextrin–drug complexes to provide prolonged drug delivery. According to our knowledge, carriers in the form of polyvinylpyrrolidone (PVP)/gelatin-based hydrogels incorporated with β-cyclodextrin–tamoxifen complexes and additionally modified with nanogold have not been presented in the literature. In this work, two series of these materials have been synthesized—with tamoxifen and with its complex with β-cyclodextrin. The process of obtaining drug carrier systems consisted of several stages. Firstly, the nanogold suspension was obtained. Next, the hydrogels were prepared via photopolymerization. The size, dispersity and optical properties of nanogold as well as the swelling properties of hydrogels, their behavior in simulated physiological liquids and the impact of these liquids on their chemical structure were verified. The release profiles of tamoxifen from composites were also determined. The developed materials showed swelling capacity, stability in tested environments that did not affect their structure, and the ability to release drugs, while the release process was much more effective in acidic conditions than in alkaline ones. This is a benefit considering their use for anticancer drug delivery, due to the fact that near cancer cells, there is an acidic environment. In the case of the composites containing the drug–β-cyclodextrin complex, a prolonged release process was achieved compared to the drug release from materials with unbound tamoxifen. In terms of the properties and the composition, the developed materials show a great application potential as drug carriers, in particular as carriers of anticancer drugs such as tamoxifen.

Currently, hydrogel materials are being widely developed and investigated. Factors affecting their properties may be mentioned, such as the types and the amounts of the reagents used for the synthesis of the hydrogel matrix and modifiers; thus, the main aim of the investigations was to check the impact of the amount of photoinitiator applied during the UV-induced polymerization of polyvinylpyrrolidone-based hydrogels incorporated with vitamin C and Aloe vera juice. The experiments that were performed were focused on determining the hydrogels’ swelling capability, behavior in simulated body fluids, hydrophilicity, chemical structure (using FT-IR spectroscopy), as well as their surface morphology and roughness. It was proven that developed materials had relatively rough surfaces, they did not degrade in simulated physiological liquids, and their swelling ratios in these media were 2.0–3.0 g/g. The only change in the pH of the incubation media—a slight decrease—was caused by the release of the modifiers into the tested liquids. Subsequently, it was demonstrated that as the amount of the photoinitiator (2-hydroxy-2-methylpropiophenone) increased, the percentage elongation decreased, and the tensile strength increased. The content of the photoinitiator in the hydrogels also influenced their wettability. All samples showed hydrophilicity; the more photoinitiator in the hydrogel structure, the lower wetting angle for water. Moreover, the greater the amount of 2-hydroxy-2-methylpropiophenone, the smoother and more homogeneous the hydrogel surface; thus, considering the demonstrated physicochemical properties of developed materials, they seem to show application potential for more advanced research regarding the development of innovative dressing materials.

The interest in the application of plant extracts as modifiers of polymers intended for biomedical purposes is constantly increasing. The therapeutical properties of the licorice root, including its anti-inflammatory and antibacterial activity, make this plant particularly promising. The same applies to silver nanoparticles showing antibacterial properties. Thus the main purpose of the research was to design hydrogel dressings containing both licorice root extract and nanosilver so as to obtain a system promoting wound regeneration processes by preventing infection and inflammation within the wound. The first step included the preparation of the plant extract via the solid-liquid extraction using the Soxhlet extractor and the synthesis of silver nanoparticles by the chemical reduction of silver ions using a sodium borohydride as a reducing agent. Subsequently, hydrogels were synthesized via photopolymerization and subjected to studies aiming at characterizing their sorption properties, surface morphology via scanning electron microscopy, and their impact on simulated physiological liquids supported by defining these liquids' influence on hydrogels' structures by FT-IR spectroscopy. Next, the tensile strength of hydrogels and their percentage elongation were determined. Performed studies also allowed for determining the hydrogels' wettability and free surface energies. Finally, the cytotoxicity of hydrogels towards L929 murine fibroblasts via the MTT reduction assay was also verified. It was demonstrated that developed materials showed stability in simulated physiological liquids. Moreover, hydrogels were characterized by high elasticity (percentage elongation within the range of 24-29%), and their surfaces were hydrophilic (wetting angles below 90°). Hydrogels containing both licorice extract and nanosilver showed smooth and homogeneous surfaces. Importantly, cytotoxic properties towards L929 murine fibroblasts were excluded; thus, developed materials seem to have great potential for application as innovative dressings.

Hydrogels belong to the group of polymers with a three-dimensional crosslinked structure, and their crosslinking density strongly affects their physicochemical properties. Here, we verified the impact of both the average molecular weight of crosslinking agents used during the photopolymerization of hydrogels and that of their content on selected properties of these materials. First, PVP-based hydrogels modified with Aloe vera juice and L-ascorbic acid were prepared using UV radiation. Next, their surface morphology was characterized via optical scanning electron microscopy, whereas their chemical structure was investigated by FT-IR spectroscopy. Moreover, we verified the tendency of the hydrogels to degrade in selected physiological liquids, as well as their tensile strength, percentage of elongation, and swelling capability. We found that the more crosslinking agent in the hydrogel matrix, the higher its tensile strength and the less elongation. The hydrogels showed the highest stability during incubation in SBF and 2% hemoglobin solution. A sharp decrease in the pH of distilled water observed during the incubation of the hydrogels was probably due to the release of Aloe vera juice from the hydrogel matrices. This was additionally confirmed by the decrease in the intensity of the absorption band derived from the polysaccharides included in this additive and by the decrease in the swelling ratio after 48 h. Importantly, all hydrogels demonstrated swelling properties, and it was proven that the higher content of the crosslinking agent in hydrogels, the lower their swelling ability.

Polymer and hydroxyapatite (HAP) composites have growing interest in bone regeneration. Commonly used for these applications is polyvinylpyrrolidone (PVP), which represents excellent biological ine...

Currently, many investigations are being performed to develop dressing materials with a positive effect on the wound healingprocess. In general, innovative dressings should ensure wound exudate absorption, constitute an external barrier limiting thepossibility of wound contamination and, importantly, also provide therapeutic properties. This work is focused on obtainingmaterials with potential use as dressings for treatment of difficult-to-heal wounds. The synthesis methodology of acrylic hydrogelsmodified with selected modifiers, i.e. arabic gum, nanogold, bee pollen and chamomile extract, was developed. Next, thesorption properties of the materials were determined as well as their behavior during the incubation in fluids imitating theenvironment of the human body. Additionally, the impact of such an incubation on their structure was evaluated by FT-IR spectroscopy.It was proved that the modifiers affected the sorption properties of hydrogels, i.e. samples with additives showed evenapprox. 2.5-fold lower swelling ability. In turn, incubation of hydrogels in simulated body fluids did not cause any rapid changesin pH, which may indicate the biocompatibility of the tested materials with the tested fluids. Thus, it may be concluded that thedeveloped materials show great application potential for biomedical purposes and may be subjected to more advanced studiessuch as cytotoxicity assessments towards selected cell lines.

Scientists look for new materials that can be used for the synthesis of drug carriers. Growing popularity is observed for poly(hydroxybutyric acid) (PHB). This biocompatible and biodegradable biopo...

Hydroxyapatite (HAp) constitutes a significant inorganic compound which due to its osteoinductivity, osteoconductivity as well as the ability to promote bone growth and regeneration is widely applied in development of biomaterials designed for bone tissue engineering. In this work, various synthesis methodologies of HAp based on the wet precipitation technique were applied, and the impact of pH of the reaction mixture, the concentration of individual reagents as well as the type of stirring applied (mechanical/magnetic) on the properties of final powders was discussed. Spectroscopic methods (Fourier transform infrared, Raman) and X-ray diffraction allowed to verify the synthesis parameters leading to obtaining calcium phosphate with 96% HAp in phase which indicated higher homogeneity of obtained powder (93.4%) than commercial HAp. Powders' morphology was evaluated using microscopic techniques while specific surface area was determined via Brunauer-Emmett-Teller analysis. Particle size distribution, porosity of powders, and stability of HAp suspensions were also characterized. It was proved that synthesis at pH = 11.0 using mechanical stirring resulted in calcium phosphate with a high phase homogeneity and homogeneous pore size distribution (6-20 nm). Moreover, obtained HAp powder showed 71.8% more specific surface area than commercial material-that is, 110 m

Among many compounds that due to their properties are widely used for preparation of ceramic composites applicable in medicine is hydroxyapatite (HAp) characterized by good osteoconductivity and os...

Core-shell nanostructures are widely used in many fields, including medicine and the related areas. An example of such structures are nanogold-shelled Fe3O4 magnetic nanoparticles. Systems consisting of a magnetic core and a shell made from nanogold show unique optical and magnetic properties. Thus, it is essential to develop the methodology of their preparation. Here, we report the synthesis methodology of Fe3O4@Au developed so as to limit their agglomeration and increase their stability. For this purpose, the impact of the reaction environment was verified. The properties of the particles were characterized via UV-Vis spectrophotometry, dynamic light scattering (DLS), X-ray diffraction (XRD), and Scanning Electron Microscopy-Energy Dispersive X-ray analysis (SEM-EDS technique). Moreover, biological investigations, including determining the cytotoxicity of the particles towards murine fibroblasts and the pro-inflammatory activity were also performed. It was demonstrated that the application of an oil and water reaction environment leads to the preparation of the particles with lower polydispersity, whose agglomerates’ disintegration is 24 times faster than the disintegration of nanoparticle agglomerates formed as a result of the reaction performed in a water environment. Importantly, developed Fe3O4@Au nanoparticles showed no pro-inflammatory activity regardless of their concentration and the reaction environment applied during their synthesis and the viability of cell lines incubated for 24 h with the particle suspensions was at least 92.88%. Thus, the developed synthesis methodology of the particles as well as performed investigations confirmed a great application potential of developed materials for biomedical purposes.

The interest in magnetic nanoparticles is constantly growing, which is due to their unique properties, of which the most useful is the possibility of directing their movement via an external magnetic field. Thus, applications may be found for them as carriers in targeted drug delivery. These nanomaterials usually form a core in a core–shell structure, and a shell may be formed via various compounds. Here, nanosilver-shelled iron oxide magnetic nanoparticles were developed. Various reaction media and various Arabic gum (stabilizer) solution concentrations were investigated to verify those that were most beneficial one in limiting their agglomeration as much as possible. The essential oil of lavender was proposed as a component of such a medium; it was used alone or in combination with distilled water as a solvent of the stabilizer. The particle size was characterized by dynamic light scattering (DLS), the chemical structure was characterized via FT-IR spectroscopy, the crystallinity was characterized by X-ray diffraction (XRD), and the surface morphology and elemental composition were verified via the SEM-EDS technique. Moreover, UV-Vis spectrophotometry was used to verify the presence of the shell made of nanosilver. Importantly, the particles’ pro-inflammatory activity and cytotoxicity towards L929 murine fibroblasts were also characterized. It was demonstrated that a 3% stabilizer solution provided a preparation of Fe3O4@Ag particles, but its stabilizing effect was not sufficient, as a suspension with micrometric particles was obtained; thus it was necessary to apply 4 h of sonication for their crushing. Next, the oil/water reaction medium was verified as beneficial in terms of nanoparticle formation. In such reaction conditions, the formation of particle agglomerates was strongly limited, and after 15 min of sonication a suspension containing only nanoparticles was obtained. The presence of a nanosilver shell was confirmed spectrophotometrically via XRD and SEM-EDS techniques. Importantly, the developed nanomaterials showed no cytotoxicity towards murine fibroblasts and no pro-inflammatory activity.

The demand for geopolymer materials is constantly growing. This, in turn, translates into an increasing number of studies aimed at developing new approaches to the methodology of geopolymer synthesis. The range of potential applications of geopolymers can be increased by improving the properties of the components. Future directions of studies on geopolymer materials aim at developing geopolymers showing excellent mechanical properties but also demonstrating significant improvement in thermal, magnetic, or sorption characteristics. Additionally, the current efforts focus not only on the materials’ properties but also on obtaining them as a result of environment-friendly approaches performed in line with circular economy assumptions. Scientists look for smart and economical solutions such that a small amount of the modifier will translate into a significant improvement in functional properties. Thus, special attention is paid to the application of nanomaterials. This article presents selected nanoparticles incorporated into geopolymer matrices, including carbon nanotubes, graphene, nanosilica, and titanium dioxide. The review was prepared employing scientific databases, with particular attention given to studies on geopolymer nanocomposites. The purpose of this review article is to discuss geopolymer nanocomposites in the context of a sustainable development approach. Importantly, the main focus is on the influence of these nanomaterials on the physicochemical properties of geopolymer nanocomposites. Such a combination of geopolymer technology and nanotechnology seems to be promising in terms of preparation of nanocomposites with a variety of potential uses.

This work focused on obtaining and characterizing hydrogels with their potential application as dressing materials for chronic wounds. The research included synthesizing chitosan-based hydrogels modified with Equisetum arvense L. (horsetail) extract via photopolymerization, and their characteristics determined with regard to the impact of both the modifier and the amount of crosslinker on their properties. The investigations included determining their sorption properties and tensile strength, evaluating their behavior in simulated physiological liquids, and characterizing their wettability and surface morphology. The release profile of horsetail extract from polymer matrices in acidic and alkaline environments was also verified. It was proved that hydrogels showed swelling ability while the modified hydrogels swelled slightly more. Hydrogels showed hydrophilic nature (all contact angles were

The interest in the application of plant extracts as modifiers of polymers intended for biomedical purposes is constantly increasing. The therapeutical properties of the licorice root, including its anti-inflammatory and antibacterial activity, make this plant particularly promising. The same applies to silver nanoparticles showing antibacterial properties. Thus the main purpose of the research was to design hydrogel dressings containing both licorice root extract and nanosilver so as to obtain a system promoting wound regeneration processes by preventing infection and inflammation within the wound. The first step included the preparation of the plant extract via the solid-liquid extraction using the Soxhlet extractor and the synthesis of silver nanoparticles by the chemical reduction of silver ions using a sodium borohydride as a reducing agent. Subsequently, hydrogels were synthesized via photopolymerization and subjected to studies aiming at characterizing their sorption properties, surface morphology via scanning electron microscopy, and their impact on simulated physiological liquids supported by defining these liquids’ influence on hydrogels’ structures by FT-IR spectroscopy. Next, the tensile strength of hydrogels and their percentage elongation were determined. Performed studies also allowed for determining the hydrogels’ wettability and free surface energies. Finally, the cytotoxicity of hydrogels towards L929 murine fibroblasts via the MTT reduction assay was also verified. It was demonstrated that developed materials showed stability in simulated physiological liquids. Moreover, hydrogels were characterized by high elasticity (percentage elongation within the range of 24–29%), and their surfaces were hydrophilic (wetting angles below 90°). Hydrogels containing both licorice extract and nanosilver showed smooth and homogeneous surfaces. Importantly, cytotoxic properties towards L929 murine fibroblasts were excluded; thus, developed materials seem to have great potential for application as innovative dressings.

In recent years, many investigations on the development of innovative dressing materials with potential applications, e.g., for cytostatics delivery, have been performed. One of the most promising carriers is albumin, which tends to accumulate near cancer cells. Here, chitosan-based hydrogels containing albumin spheres and Aloe vera juice, designed for the treatment of skin cancers or burn wounds resulting from radiotherapy, were developed. The presence of albumin in hydrogel matrices was confirmed via Fourier transform infrared (FT-IR) and Raman spectroscopy. Albumin spheres were clearly visible in microscopic images. It was proved that the introduction of albumin into hydrogels resulted in their increased resistance to the tensile load, i.e., approximately 30% more force was needed to break such materials. Modified hydrogels showed approximately 10% more swelling ability. All hydrogels were characterized by hydrophilicity (contact angles were &lt, 90°) which may support the regeneration of epithelial cells and non-cytotoxicity towards murine fibroblasts L929 and released Aloe vera juice more effectively in an acidic environment than in a neutral one wherein spheres introduced into the hydrogel matrix extended the release time. Thus, the developed materials, due to their chemical composition and physicochemical properties, constitute promising materials with great application potential for biomedical purposes.

Hydrogels belong to the group of materials with growing interest on the market of polymers. In this article, hydrogels based on Beetosan were obtained using ultraviolet (UV) radiation. Main component of hydrogel matrix-Beetosan-is chitosan obtained from naturally died honeybees. Such hydrogels were modified with active substances, that is, caffeine, bee pollen, Salvia officinalis (sage), and Aloe vera juice. Next, the analysis of cytotoxicity of hydrogels in relation to murine fibroblasts by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide and neutral red uptake assays were conducted. Furthermore, surface morphology, tensile strength, geometry, and roughness of hydrogels were characterized. Hydrogels did not show cytotoxicity to recommended L929 murine fibroblasts. These polymers did not affect adversely the growth and viability of these cells. Moreover, Beetosan hydrogels were characterized by flexibility as well as by diversified surface morphology that could indicate their high absorbency. Therefore these materials may be considered as useful for biomedical purposes with special emphasis on application as modern wound dressings that not only absorb wound exudate but also contain natural substances with therapeutic properties that is beneficial from the point of view of wound healing process.

Hydrogels belong to the group of polymers that are more and more often considered as innovative dressing materials. It is important to develop materials showing the most advantageous properties from the application viewpoint wherein in the case of hydrogels, the type and the amount of the crosslinking agent strongly affect their properties. In this work, PVP-based hydrogels containing Aloe vera juice and L-ascorbic acid were obtained via UV-induced polymerization. Next, their surface morphology (via both optical, digital and scanning electron microscope), sorption capacity, tensile strength, and elongation were characterized. Their structure was analyzed via FT-IR spectroscopy wherein their impact on the simulated body liquids was verified via regular pH and temperature measurements of these liquids during hydrogels’ incubation. It was demonstrated that as the amount of the crosslinker increased, the polymer structure was more wrinkled. Next, hydrogels showed relatively smooth and only slightly rough surface, which was probably due to the fact that the modifiers filled also the outer pores of the materials. Hydrogels demonstrated buffering properties in all incubation media, wherein during the incubation the release of Aloe vera juice probably took place as evidenced by the decrease in the pH of the incubation media and the disappearance of the absorption band deriving from the polysaccharides included in the composition of this additive. Next, it was proved that as the amount of the crosslinker increased, hydrogels’ crosslinking density increased and thus their swelling ratio decreased. Hydrogels obtained using a crosslinking agent with higher average molecular weight showed higher swelling ability than the materials synthesized using crosslinker with lower average molecular weight. Moreover, as the amount of the crosslinking agent increased, the tensile strength of hydrogels as well as their percentage elongation also increased.

Recently, there has been great interest in the application of polysaccharides in the preparation of diverse biomaterials which result from their biocompatibility, biodegradability and biological activity. In this work, the investigations on chitosan/poly(aspartic acid)-based hydrogels modified with starch were described. Firstly, a series of hydrogel matrices was prepared and investigated to characterize their swelling properties, structure via FT-IR spectroscopy, elasticity and tensile strength using the Brookfield texture analyzer as well as their impact on simulated physiological liquids. Hydrogels consisting of chitosan and poly(aspartic acid) in a 2:1 volume ratio were elastic (9% elongation), did not degrade after 30-day incubation in simulated physiological liquids, exhibited a relative biocompatibility towards these liquids and similar swelling in each absorbed medium. This hydrogel matrix was modified with starch wherein two of its form were applied—a solution obtained at an elevated temperature and a suspension obtained at room temperature. Hydrogels modified with hot starch solution showed higher sorption that unmodified materials. This was probably due to the higher starch inclusion (i.e., a larger number of hydrophilic groups able to interact with the adsorbed liquid) when this polysaccharide was given in the form of a hot solution. Hydrogels modified with a cold starch suspension had visible heterogeneous inequalities on their surfaces and this modification led to the obtainment materials with unrepeatable structures which made the analysis of their properties difficult and may have led to misleading conclusions.

This work investigates the possibility of using thiolated silicone oils as new components in protective creams and their impact on the efficacy of these products. Thiolated silicone oils were synthesized by amide bond formation between primary amino groups of poly17dimethylsiloxane-co-(3-aminopropyl)-methylsiloxane] and carboxylic groups of thiol ligand (3-mercaptopropionic acid) with carbodiimide as a coupling agent. To evaluate and compare the properties of these kinds of thiomers, three different emulsion o/w types were obtained. Emulsion E1 contained methyl silicone oil, E2 poly[dimethylsiloxane-co-(3-aminopropyl)-methylsiloxane], and E3 thiolated silicone oil (silicone-MPA), respectively. Physicochemical properties, including pH, conductivity, droplet size distribution, viscosity, and stability, were assessed. The efficacy of barrier creams in the prevention of occupational skin diseases depends on their mechanical and rheological properties. Thus, the method which imitates the spreadability conditions on the skin and how structure reconstruction takes places was performed. We also investigated textural profile, bioadhesion, protection against water and detergents, and water vapor permeability. Emulsion E3 was characterized by beneficial occlusion, spreadability, and adhesion properties. These features with prolonged residence time on the skin can make designed barrier creams more preferable for consumers.

The aspect of drug delivery is significant in many biomedical subareas including tissue engineering. Many studies are being performed to develop composites with application potential for bone tissue regeneration which at the same provide adequate conditions for osteointegration and deliver the active substance conducive to the healing process. Hydroxyapatite shows a great potential in this field due to its osteoinductive and osteoconductive properties. In the paper, hydroxyapatite synthesis via the wet precipitation method and its further use as a ceramic phase of polymer–ceramic composites based on PVP/PVA have been presented. Firstly, the sedimentation rate of hydroxyapatite in PVP solutions has been determined, which allowed us to select a 15% PVP solution (sedimentation rate was 0.0292 mm/min) as adequate for preparation of homogenous reaction mixture treated subsequently with UV radiation. Both FT-IR spectroscopy and EDS analysis allowed us to confirm the presence of both polymer and ceramic phase in composites. Materials containing hydroxyapatite showed corrugated and well-developed surface. Composites exhibited swelling properties (hydroxyapatite reduced this property by 25%) in simulated physiological fluids, which make them useful in drug delivery (swelling proceeds parallel to the drug release). The short synthesis time, possibility of preparation of composites with desired shapes and sizes and determined physicochemical properties make the composites very promising for biomedical purposes.

The novelty of the research involves designing the measurement methodology aimed at determining the structure–property relationships in the chitosan-based hydrogels containing yellow tea extract. Performed investigations allowed us to determine the swelling properties of hydrogels in selected time intervals, evaluate the mutual interactions between the hydrogels and simulated physiological liquids via pH measurements and directly assess the impact of such interactions on the chemical structure of hydrogels using Fourier transform infrared (FT-IR) spectroscopy and their wettability by the measurements of the flatness of the drop on the surface of the tested samples via the static drop method. Next, the surface morphology of hydrogels was characterized by the Scanning Electron Miscorcopy (SEM) and their elasticity under the tension applied was also verified. It was proved that incubation in simulated physiological liquids resulted in a decrease in contact angles of hydrogels, even by 60%. This also caused their certain degradation which was reflected in lower intensities of bands on FT-IR spectra. Further, 23% v/v yellow tea extract in hydrogel matrices caused the decrease of their tensile strength. An increase in the amount of the crosslinker resulted in a decrease in the sorption capacity of hydrogels wherein their modification caused greater swelling ability. In general, the investigations performed provided much information on the tested materials which may be meaningful considering their application, e.g., as dressing materials.

The main purpose of this work was to determine the impact of the location of bee apiaries in diff erent parts of Poland on the physicochemical properties of selected bee honeys. Studies focused on the determination of the antioxidant properties of apiproducts. Th e water content in honeys as well as their pH values were also analyzed. Four types of honeys (honeydew, linden, buckwheat, acacia) originating from various parts of Poland were selected for the research. Based on the obtained results, it can be stated that the examined honeys differed in physicochemical properties, which was related to the diff erences in their chemical composition. All honeys tested showed antioxidant properties. It can also be found that the water content in analyzed products was related to their origin and variety. Analyzing pH measurements, it can also be observed that all tested samples were characterized by acidic properties.

In this work, synthesis and investigations on chitosan-based hydrogels modified with Aloe vera juice are presented. These materials were synthesized by UV radiation. Investigations involved analysis of chemical structure by FTIR spectroscopy, sorption properties in physiological liquids, strength properties by texture analyzer, surface topography by Atomic Force Microscopy (AFM technique), and in vitro cytotoxicity by MTT test using L929 murine fibroblasts. Particular attention was focused both on determining the impact of the amount and the molecular weight of the crosslinker used for the synthesis as well as on the introduced additive on the properties of hydrogels. It was proven that modified hydrogels exhibited higher swelling ability. Introduced additive affected the tensile strength of hydrogels&mdash, modified materials showed 23% higher elongation. The greater amount of the crosslinker used in the synthesis, the more compact the structure, leading to the lower elasticity and lower sorption of hydrogels was reported. Above 95%, murine fibroblasts remained viable after 24 h incubation with hydrogels. It indicates that tested materials did not exhibit cytotoxicity toward these lines. Additionally, materials with Aloe vera juice were characterized by lower surface roughness. Conducted investigations allowed us to state that such modified hydrogels may be considered as useful for biomedical purposes.

Barium titanate is a ferroelectric perovskite with unique electric properties, therefore, it is widely applied in the fabrication of inorganic coatings or thin films, capacitors, or in the production of devices for energy storage and conversion. This paper describes the mechanochemical synthesis of BaTiO3 from BaO and TiO2 using a ball mill. XRD analysis allowed concluding that barium titanate was formed after 90 min of mechanochemical grinding. It was also proved by spectroscopic analysis and the band corresponding to Ti&ndash, O vibrations on obtained Fourier Transform Infrared (FT-IR) spectra. The specific surface area of obtained powder was 25.275 m2/g. Next, formed perovskite was dispersed in an acrylic poly(ethylene glycol) (superabsorbent polymer suspension, SAP) suspension prepared using microwave radiation. Final suspensions differed in the concentration of SAP applied. It was proven that the increase of SAP concentration does not affect the acidity of the suspension, but it does increase its dynamic viscosity. A sample with 83 wt.% of SAP reached a value of approximately 140 mPa∙s. Dispersions with higher values of SAP mass fraction exhibited lower sedimentation rates. Molecules such as SAP may adsorb to the surface of particles and thus prevent their agglomeration and make them well monodispersed. Based on the performed experiments, it can be concluded that acrylic poly(ethylene glycol) suspension is a suitable fluid that may stabilize barium titanate dispersions.

In this work, synthesis and investigations on chitosan-based hydrogels modified with Aloe vera juice are presented. These materials were synthesized by UV radiation. Investigations involved analysis of chemical structure by FTIR spectroscopy, sorption properties in physiological liquids, strength properties by texture analyzer, surface topography by Atomic Force Microscopy (AFM technique), and in vitro cytotoxicity by MTT test using L929 murine fibroblasts. Particular attention was focused both on determining the impact of the amount and the molecular weight of the crosslinker used for the synthesis as well as on the introduced additive on the properties of hydrogels. It was proven that modified hydrogels exhibited higher swelling ability. Introduced additive affected the tensile strength of hydrogels—modified materials showed 23% higher elongation. The greater amount of the crosslinker used in the synthesis, the more compact the structure, leading to the lower elasticity and lower sorption of hydrogels was reported. Above 95%, murine fibroblasts remained viable after 24 h incubation with hydrogels. It indicates that tested materials did not exhibit cytotoxicity toward these lines. Additionally, materials with Aloe vera juice were characterized by lower surface roughness. Conducted investigations allowed us to state that such modified hydrogels may be considered as useful for biomedical purposes.

In paper preparation and characterization of hydrogels based on chitosan of bees’ origin and modified with caffeine have been reported. Surface morphology of hydrogel materials including th...

Owing to their multifunctional pharmacological profiles (including dual 5-HT1A/5-HT7 action), arylpiperazine derivatives are widely used for treating central nervous system diseases including the depression or neuropathic pain. Herein we describe the design, synthesis and evaluation of biological activity of novel 5-HT7 ligands derived of 2,4,6-triamino-1,3,5-triazine. The studied compounds showed affinity and high selectively towards 5-HT7 receptor with the two most active compounds 34 (Ki = 61 nM), 22 (Ki = 109 nM) showing good metabolic stability and moderate affinity to CYP3A4 isoenzyme. Compound 22 had high hepatotoxicity at a concentration below 50 μM, while compound 34 showed low hepatotoxicity even at a concentration above 50 μM.

Nowadays, a great attention is directed into development of innovative multifunctional composites which may support bone tissue regeneration. This may be achieved by combining collagen and hydroxyapatite showing bioactivity, osteoconductivity and osteoinductivity with such biocompatible polymers as polyvinylpyrrolidone (PVP) and poly(vinyl alcohol) (PVA). Here PVA/PVP-based composites modified with hydroxyapatite (HAp, 10 wt.%) and collagen (30 wt.%) were obtained via UV radiation while two types of collagen were used (fish and bovine) and crosslinking agents differing in the average molecular weight. Next, their chemical structure was characterized using Fourier transform infrared (FT-IR) spectroscopy, roughness of their surfaces was determined using a stylus contact profilometer while their wettability was evaluated by a sessile drop method followed by the measurements of their surface free energy. Subsequently, swelling properties of composites were verified in simulated physiological liquids as well as the behavior of composites in these liquids by pH measurements. It was proved that collagen-modified composites showed higher swelling ability (even 25% more) compared to unmodified ones, surface roughness, biocompatibility towards simulated physiological liquids and hydrophilicity (contact angles lower than 90°). Considering physicochemical properties of developed materials and a possibility of the preparation of their various shapes and sizes, it may be concluded that developed materials showed great application potential for biomedical use, e.g., as materials filling bone defects supporting their treatments and promoting bone tissue regeneration due to the presence of hydroxyapatite with osteoinductive and osteoconductive properties.

Hydrogels due to their unique properties are characterized by a wide range of applications. In presented research a series of hydrogel based on chitosan and modified with nanogold have been prepare...

Capability of materials to self-repair is an innovative and unique property from a point of view both chemistry and physics. Moreover, such property could arouse special interests if such a...

Aripiprazole is a widely used antipsychotic approved by the FDA (Food and Drug Administration) in 2002. Methods for preparation of aripiprazole mainly involve the use of expensive and toxic solvents, and the reaction time can be even several hours long. Our method allows to obtain aripiprazole with a yield of approximately 70–80% over just a few minutes using solvent-free conditions in the presence of PTC (Phase Transfer Catalysts) and microwave radiation.

Chitosan belongs to the group of biopolymers with increasing range of potential applications therefore searching for new raw materials as well as new techniques of obtaining of this polysaccharide are currently a subject of interest of many scientists. Presented manuscript describes preparation of chitosan from crickets. Obtainment of final product required a number of processes aimed at removal of undesirable substances such as waxes, mineral salts, proteins or pigments from above-mentioned insects. Chemical structure of fractions obtained after each step was compared with the structure of commercial chitosan by means of techniques such as X-ray diffraction and FT-IR spectroscopy. Final product was subsequently used for preparation of polymer capsules that were modified with active substance characterized by antibacterial and anticancer activity—nisin. Next, sorption capacity of obtained materials was evaluated as well as a release profile of active substance in different environments. Based on the conducted research it can be concluded that crickets constitute an alternative for shellfish and other conventional sources of chitosan. Furthermore, obtained capsules on the basis of such prepared chitosan can be considered as drug delivery systems which efficiency of release of active substance is bigger in alkaline environments.

Praca byla realizowane w ramach projektu LIDER/033/697/L-5/13/NCBR/2014 finansowane przez Narodowe Centrum Badan i Rozwoju (NCBiR).

Chitosan based hydrogels are commonly applied in various fields of medicine and pharmacy. Modification of hydrogel polymers using nanosilver particles may result in formation of materials with enhanced antibacterial properties. In this article synthesis of hydrogel materials based on chitosan and modified with silver nanoparticles is presented. First, preparation and characterization of silver nanoparticles using UV-vis spectroscopy has been shown. Hydrogels modified with nanosilver particles were subjected to the measurements of swelling ability and in vitro tests in distilled water and Simulated Body Fluid (SBF), respectively. Additionally, evaluation of antibacterial properties against Staphylococcus aureus and Enterococcus faecalis as well as results of cytotoxicity of hydrogel materials modified with silver nanoparticles conducted by means of XTT and MTT assays using dermis cells BJ (CRL-2522TM) have been presented.

Many studies are being performed to develop effective carriers for controlled cytostatic delivery wherein albumin is a promising material due to its tendency to accumulate near cancer cells. The novelty of this work involves the development of the synthesis methodology of albumin nanoparticles and their biological and physicochemical evaluation. Albumin particles were obtained via the salt-induced precipitation and K3PO4 was used as a salting-out agent. Various concentrations of protein and salting-out agent solutions were mixed using a burette or a syringe system. It was proved that the size of the particles depended on the concentrations of the reagents and the methodology applied. As a result of a process performed using a burette and 2 M K3PO4, albumin spheres having a size 5–25 nm were obtained. The size of nanospheres and their spherical shape was confirmed via TEM analysis. The use of a syringe system led to preparation of particles of large polydispersity. The highest albumin concentration allowing for synthesis of homogeneous particles was 2 g/L. The presence of albumin in spheres was confirmed via the FT-IR technique and UV-Vis spectroscopy. All samples showed no cytotoxicity towards normal human dermal fibroblasts and no hemolytic properties against human erythrocytes (the hemolysis did not exceed 2.5%).

Regenerative medicine is becoming a rapidly evolving technique in today’s biomedical progress scenario. Scientists around the world suggest the use of naturally synthesized biomaterials to repair and heal damaged cells. Hydroxyapatite (HAp) has the potential to replace drugs in biomedical engineering and regenerative drugs. HAp is easily biodegradable, biocompatible, and correlated with macromolecules, which facilitates their incorporation into inorganic materials. This review article provides extensive knowledge on HAp and collagen-containing compositions modified with drugs, bioactive components, metals, and selected nanoparticles. Such compositions consisting of HAp and collagen modified with various additives are used in a variety of biomedical applications such as bone tissue engineering, vascular transplantation, cartilage, and other implantable biomedical devices.

The paper presents characteristic, applications as well as worldwide demand for chitosan and the resulting development of the methodology of obtaining this biopolymer. Currently, chitosan is one of the leading polysaccharides on the polymer market. This results from its properties such as biodegradability, biocompatibility, antimicrobial activity, adsorption capability and chelating properties. Therefore this polysaccharide finds application in a wide variety of areas such as medicine and related fields, environmental protection, food science or agriculture. Due to the growing interest in this biopolymer—worldwide demand for chitin (chitosan is its deacetylated derivative) in 2015 was 60,000 t—new sources of chitosan as well as new methods of its extraction are currently a research subject of many scientists. An important issue is a development of methodologies in accordance with recommendations of the sustainable production trend, i.e. considering such issues as e.g. reduction in the energy consumption, reuse and recycle of reagents or reduction in the amount of generated waste. Therefore many studies are currently carried out to obtain chitosan using methods that will have the least impact on the environment.

Currently, increasing attention is being paid to issues related to environmental protection, waste management, as well as to the development of polymers with useful properties. The research presented here involved preparation of hydrogels based on Beetosan® - a chitosan derived from the multi-stage processing of dead bees. Moreover, hydrogels were additionally modified with natural substances - i.e. bee pollen and extract of Salvia officinalis (sage) that are well known for the presence of many compounds with beneficial properties from a medical point of view. Materials have been first obtained by photopolymerization. Then, their surface morphology, wettability and cytotoxicity to selected cell lines have been determined. It can be stated that such combination of Beetosan® hydrogel matrix and the mentioned additives resulted in a preparation of polymers characterized by negative impact on cancer cells. Impact of hydrogels with sage is slightly more intense due to the presence of substances such as ursalic or rosmaric acid that are characterized to have anticancer activity. Such negative impact has not been observed in case of studies using fibroblasts. Furthermore, addition of natural substances into hydrogels resulted in a more homogeneous surface and in the decrease of wettability angle of the tested polymers. It can be concluded that the use of natural-derived reagents and synthesis of polymers using these reagents (as a result of environmentally friendly photopolymerization) yields materials with interesting properties for medical purposes, with particular emphasis on antitumor activity, and without significant negative impact on fibroblasts.

Hydrogels belong to the group of polymers that recently become more and more popular. This is a result of unique properties of the mentioned materials such as biocompatibility, biodegradability as well as a great sorption capacity. Combination of such polymers with gold nanoparticles results in the preparation of innovative materials that can be applicable in wide range of areas with special emphasis on medicine. In present publication series of chitosan based hydrogels modified with gold nanoparticles were prepared. These materials were subsequently characterized by a number of physicochemical analysis concerning determination of cytotoxicity to epidermal cells. Based on these research it can be concluded that hydrogels containing small quantities of gold nanoparticles do not exhibit toxicity in relation to these cells. Furthermore, it can be said that addition of nanogold into hydrogel resulted in a decrease of its porosity as well as in a slight decrease of the sorption capacity of materials tested. Prepared polymers were characterized by biocompatibility in relation to simulated body fluid. Proposed hydrogels constitute an interesting type of materials that could be potentially considered for biomedical use.