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Recent advancements in cultural heritage preservation have increasingly focused on the development and application of new composites, harnessing the diverse properties of their components. This study reviews the current state of research and practical applications of these innovative materials, emphasizing the use of inorganic phosphatic materials (in particular the hydroxyapatite) and various polymers. The compatibility of phosphatic materials with calcareous stones and the protective properties of polymers present a synergistic approach to addressing common deterioration mechanisms, such as salt crystallization, biological colonization, and mechanical weathering. By examining recent case studies and experimental results, this paper highlights the effectiveness, challenges, and future directions for these composites in cultural heritage conservation. The findings underscore the potential of these materials to enhance the durability and aesthetic integrity of heritage stones, promoting sustainable and long-term preservation solutions. [ABSTRACT FROM AUTHOR]

Natural clay minerals are among the most versatile materials used in the biomedical field. Palygorskite has found various applications in this field, from the treatment of diarrheal diseases in the past to materials with antibacterial properties and platforms carrying bioactive compounds used in the treatment of diseases, cosmetic and healthcare products in the present. In this study, a possible delivery method of some bioactive asymmetric β-diketonic compounds is presented. Palygorskite modified with amphionic groups (P) and copper ions (PCu) was used as a platform to load bioactive curcumin derivatives (1 and 2). By varying the copper ions, the amounts of charged active compounds were monitored. Studies have shown that the hybrid materials resulting from the loading of 1 and 2 compounds on palygorskite with 30% copper ions (PCu30) can be used as delivery methods for these asymmetric curcumin derivatives, while palygorskite with 50% copper ions(PCu50) loaded with the same type of bioactive compounds has antibacterial properties. [ABSTRACT FROM AUTHOR]

This work aims to evaluate the potential use of natural wastes (in particular, clam shells) to synthesize one of the most well-known and versatile materials from the phosphate mineral group, hydroxyapatite (HAP). The obtained material was characterized in terms of morphology and composition using several analytical methods (scanning electron microscopy—SEM, X-ray diffraction—XRD, X-ray fluorescence—XRF, Fourier transform infrared spectroscopy—FTIR, thermal analysis—TGA, and evaluation of the porosity and specific surface characteristics by the Brunauer–Emmett–Teller—BET method) in order to confirm the successful synthesis of the material and to evaluate the presence of potential secondary phases. The developed material was further doped with iron oxide (HAP-Fe) using a microwave-assisted method, and both materials were evaluated in terms of photocatalytic activity determined by the photodecomposition of methylene blue (MB) which served as a contaminant model. The best results (approx. 33% MB degradation efficiency, after 120 min. of exposure) were obtained for the hydroxyapatite material, superior to the HAP-Fe composite (approx. 27%). The utilization of hydroxyapatite obtained from clam shells underscores the importance of sustainable and eco-friendly practices in materials syntheses. By repurposing waste materials from the seafood industry, we not only reduce environmental impact, but also create a valuable resource with diverse applications, contributing to advancements in both healthcare and environmental protection. [ABSTRACT FROM AUTHOR]

Nosocomial infections represent a major threat within healthcare systems worldwide, underscoring the critical need for materials with antimicrobial properties. This study presents the development of polyurethane foam embedded with silver nanoparticles (PUF/AgNPs) using a rapid, eco-friendly, in situ radiochemical synthesis method. The nanocomposites were characterized by UV–vis and FTIR spectroscopy, scanning electron microscopy coupled with energy dispersive X-ray technique (SEM/EDX), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), tensile and compression strengths, antimicrobial activity, and foam toxicity tests. The resulting PUF/AgNPs demonstrated prolonged stability (over 12 months) and good dispersion of AgNPs. Also, the samples presented higher levels of hardness compared to samples without AgNPs (deformation of 1682 µm for V1 vs. 4307 µm for V0, under a 5 N force), tensile and compression strength of 1.80 MPa and 0.34 Mpa, respectively. Importantly, they exhibited potent antimicrobial activity against a broad range of bacteria (including Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and Enterococcus faecalis) and a fungal mixture (no fungal growth on the sample surface was observed after 28 days of exposure). Furthermore, these materials were non-toxic to human keratinocytes, which kept their specific morphology after 24 h of incubation, highlighting their potential for safe use in biomedical applications. We envision promising applications for PUF/AgNPs in hospital bed mattresses and antimicrobial mats, offering a practical strategy to reduce nosocomial infections and enhance patient safety within healthcare facilities. [ABSTRACT FROM AUTHOR]

Metal nanoparticle phytosynthesis has become, in recent decades, one of the most promising alternatives for the development of nanomaterials using "green chemistry" methods. The present work describes, for the first time in the literature, the phytosynthesis of silver nanoparticles (AgNPs) using extracts obtained by two methods using the aerial parts of Marrubium vulgare L. The extracts (obtained by classical temperature extraction and microwave-assisted extraction) were characterized in terms of total phenolics content and by HPLC analysis, while the phytosynthesis process was confirmed using X-ray diffraction and transmission electron microscopy, the results suggesting that the classical method led to the obtaining of smaller-dimension AgNPs (average diameter under 15 nm by TEM). In terms of biological properties, the study confirmed that AgNPs as well as the M. vulgare crude extracts reduced the viability of human gingival fibroblasts in a concentration- and time-dependent manner, with microwave-assisted extracts having the more pronounced effects. Additionally, the study unveiled that AgNPs transiently increased nitric oxide levels which then decreased over time, thus offering valuable insights into their potential therapeutic use and safety profile. [ABSTRACT FROM AUTHOR]

The present work aims to study the possibilities of developing silver nanoparticles using natural extracts of grape pomace wastes originating from the native variety of Fetească Neagră 6 Șt. This study focused on investigating the influence of grape pomace extract obtained by two different extraction methods (classical temperature extraction and microwave-assisted extraction) in the phytosynthesis process of metal nanoparticles. The total phenolic content of the extracts was assessed using the spectrophotometric method with the Folin–Ciocâlteu reagent, while the identification and quantification of specific components were conducted through high-performance liquid chromatography with a diode array detector (HPLC-DAD). The obtained nanoparticles were characterized by UV–Vis absorption spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM), along with assessing their antioxidant and antimicrobial properties against Gram-positive bacteria. The data collected from the experiments indicated that the nanoparticles were formed in a relatively short period of time (96 h) and, for the experimental variant involving the use of a 1:1 ratio (v/v, grape pomace extract: silver nitrate) for the nanoparticle phytosynthesis, the smallest crystallite sizes (from X-ray diffraction—4.58 nm and 5.14 nm) as well as spherical or semispherical nanoparticles with the lowest average diameters were obtained (19.99–23 nm, from TEM analysis). The phytosynthesis process was shown to enhance the antioxidant properties (determined using the DPPH assay) and the antimicrobial potential (tested against Gram-positive strains) of the nanoparticles, as evidenced by comparing their properties with those of the parent extracts; at the same time, the nanoparticles exhibited a selectivity in action, being active against the Staphylococcus aureus strain while presenting no antimicrobial potential against the Enterococcus faecalis strain. [ABSTRACT FROM AUTHOR]

Hyssop (Hyssopus officinalis L.) and oregano (Origanum vulgare L.), traditionally used for their antimicrobial properties, can be considered viable candidates for nanotechnology applications, in particular for the phytosynthesis of metal nanoparticles. The present work aims to evaluate the potential application of hyssop and oregano for the phytosynthesis of silver nanoparticles, as well as to evaluate the biological activities of their extracts and obtained nanoparticles (antioxidant potential, as well as cell viability, inflammation level and cytotoxicity in human fibroblasts HFIB-G cell line studies). In order to obtain natural extracts, two extraction methods were applied (classical temperature extraction and microwave-assisted extraction), with the extraction method having a major influence on their composition, as demonstrated by both the total phenolic compounds (significantly higher for the microwave-assisted extraction; the oregano extracts had consistently higher TPC values, compared with the hyssop extracts) and in terms of individual components identified via HPLC. The obtained nanoparticles ware characterized via X-ray diffraction (XRD) and transmission electron microscopy (TEM), with the lowest dimension nanoparticles being recorded for the nanoparticles obtained using the oregano microwave extract (crystallite size 2.94 nm through XRD, average diameter 10 nm via TEM). The extract composition and particle size also influenced the antioxidant properties (over 60% DPPH inhibition being recorded for the NPs obtained using the oregano microwave extract). Cell viability was not affected at the lowest tested concentrations, which can be correlated with the nitric oxide level. Cell membrane integrity was not affected after exposure to classic temperature hyssop extract-NPs, while the other samples led to a significant LDH increase. [ABSTRACT FROM AUTHOR]

Grapevine cultivation over an extended period has led to a favorable evolution of Romanian viticulture, bringing social benefits through improved dietary regimes and contributing to the country's economy through the export of quality wine products. Nevertheless, contemporary challenges such as population growth and energy crises necessitate sustainable approaches. Waste from the wine industry, such as grape pomace, yeast, leaves, and vine canes, poses a significant environmental problem. Composting these wastes can provide a sustainable solution, generating compost with high agronomic value. Additionally, wine production generates waste that can be valorized in various industries to obtain innovative products. Sustainable management of grapevine waste can contribute to more efficient use of plant resources and reduce environmental impact. Moreover, the class of chemical compounds found in the Vitis genus has diverse applications, and their valorization can enhance horticultural production, as well as the textile, food, and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

With the technological developments witnessed in recent decades, nanotechnology and nanomaterials have found uses in several common applications and products we encounter daily. On the other hand, polyurethane (PU) foams represent an extremely versatile material, being widely recognized for their extensive application possibilities and possessing a multitude of fundamental attributes that enhance their broad usability across various application fields. By combining the versatility of PU with the antimicrobial properties of nanoparticles, this emerging field holds promise for addressing the urgent need for effective antimicrobial materials in various applications. In this comprehensive review, we explore the synthesis methods, properties and applications of these nanocomposite materials, shedding light on their potential role in safeguarding public health and environmental sustainability. The main focus is on PU foams containing metal and metal oxide nanoparticles, but a brief presentation of the progress documented in the last few years regarding other antimicrobial nanomaterials incorporated into such foams is also given within this review in order to obtain a larger image of the possibilities to develop improved PU foams. [ABSTRACT FROM AUTHOR]

The aims of the present study were to evaluate for the first time the chemical composition and antioxidant, antibacterial, antifungal and antiproliferative potentials of the Romanian George 90 lavender species, as well as parental species, L. angustifolia and L. latifolia. The L. angustifolia, L. latifolia and George 90 essential oils were analyzed by GC-MS/MS and the L. angustifolia, L. latifolia and George 90 hydroalcoholic extracts were analyzed by HPLC-DAD. The antioxidant, antibacterial, antifungal and antiproliferative assays revealed that all the investigated species showed significant activities. The results highlighted the chemical composition and the promising biological potentials of the L. angustifolia, L. latifolia and George 90 lavender species, validating their ethnomedicinal value, which offers potential applications as natural drugs. [ABSTRACT FROM AUTHOR]

The medical sector is one of the biggest consumers of single-use materials, and while the insurance of sterile media is non-negotiable, the environmental aspect is a chronic problem. Nanocellulose (NC) is one of the safest and most promising materials that can be used in medical applications due to its valuable properties like biocompatibility and biodegradability, along with its good mechanical properties and high water uptake capacity. However, NC has no bactericidal activity, which is a critical need for the effective prevention of infections in chronic diabetic wound dressing applications. Therefore, in this work, a natural product, propolis extract (PE), was used as an antibacterial agent, in different amounts, together with NC to obtain sponge-like structures (NC/PE). The scanning electron microscope (SEM) images showed well-impregnated cellulose fibers and a more compact structure with the addition of PE. According to the thermogravimetric analysis (TGA), the samples containing PE underwent thermal degradation before the unmodified NC due to the presence of volatile compounds in the extract. However, the peak degradation temperature in the first derivative thermogravimetric curves was higher for all the sponges containing PE when compared to the unmodified NC. The antibacterial efficacy of the samples was tested against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, as well as on two clinically resistant isolates. The samples completely inhibited the development of Staphylococcus aureus, and Pseudomonas aeruginosa was partially inhibited, while Escherichia coli was resistant to the PE action. Considering the physical and biological properties along with the environmental and economic benefits, the development of an NC/PE wound dressing seems promising. [ABSTRACT FROM AUTHOR]

Anthropogenic activities lead to the issue of new classes of pollutants in the environment that are not currently monitored in environmental studies. This category of pollutants (known as emerging contaminants) includes a very wide range of target substances, such as pharmaceuticals, plant protection products, personal care products, dyes, toxins, microplastics and many other industrially important intermediaries. Together with an increasing demand for clean water (both for agricultural necessities and for the increasing population consumption), the need for the removal of emerging pollutants, simultaneously with the current "green chemistry" approach, opens the door for the industrial application of natural polymers in the area of environmental protection. Recent developments in this area are presented in this paper, as well as the application of these particular natural materials for the removal of other contaminants of interest (such as radioisotopes and nanoparticles). The current knowledge regarding the processes' kinetics is briefly presented, as well as the future development perspectives in this area. [ABSTRACT FROM AUTHOR]

The present work describes, for the first time in the literature, the phytosynthesis of silver nanoparticles using Leonurus cardiaca L. extracts. The influence of the extraction method (classical temperature extraction and microwave extraction), as well as of the extract concentration on the characteristics of the nanoparticles, was studied using analytical methods, such as UV-Vis spectrometry, X-ray diffraction, dynamic light scattering, and transmission electron microscopy. Experimental data suggest that use of lower extract concentration leads to smaller dimensions nanoparticles, the same effect using the extract obtained by microwave-assisted extraction. The smallest recorded crystallite sizes (by X-ray diffraction) were under 3 nm. The antioxidant properties (determined by the DPPH assay) and the antimicrobial potential (determined against Gram-negative and Gram-positive strains) are enhanced by the phytosynthesis process (as demonstrated by the comparison of the nanoparticles' properties with the parent extracts). The present work could also represent an important step in obtaining nanoparticles with enhanced properties and controlled morphologies, but also offers information on the phytosynthesis of metallic nanoparticles using low extract concentrations. [ABSTRACT FROM AUTHOR]

The continuous degradation of cultural heritage artifacts (due to different factors, including the rising air pollution, climate change or excessive biological activity, among others) requires the continuous development of protection strategies, technologies and materials. In this regard, polyelectrolytes have offered effective ways to fight against degradation but also to conserve the cultural heritage objects. In this review, we highlight the key developments in the creation and use of polyelectrolytes for the preservation, consolidation and cleaning of the cultural heritage artifacts (with particular focus on stone, metal and artifacts of organic nature, such as paper, leather, wood or textile). The state of the art in this area is presented, as well as future development perspectives. [ABSTRACT FROM AUTHOR]

Starting from the well-known antimicrobial properties of silver nanoparticles, the goal of this study is to evaluate the influence of two "green" recipes, namely an alcoholic extract of Dryopteris filix-mas (L.) Schott and a dispersion of silver nanoparticles phytosynthesized using the extract on grapevine pathogens. The influence of some grapevine parameters (pith/wood rapport, soluble sugars, starch, total sugars, total water content, length of young shoots, number of grapes) in field experiments was also studied. The study was conducted on four clones (Feteasca alba 97 St., Feteasca neagra 6 St., Feteasca regala 72 St., and Cabernet Sauvignon 131 St.) located in vegetation pots inside a greenhouse. For the phytosynthesis of the silver nanoparticles (AgNPs) we used a scaled-up technology, allowing us to obtain large quantities of nanoparticles-containing solution. The AgNPs analysis by X-ray diffraction and transmission electron microscopy confirmed the synthesis of spherical and quasi-spherical nanoparticles of 17 nm average diameter and 6.72 nm crystallite size. The field experiments registered different responses of the four clones to the treatment, using both the natural extracts and phytosynthesized nanoparticles solution. Both recipes exhibited a protective effect against the Uncinula necator pathogen. For the treatment using phytosynthesized nanoparticles, significant increases in the pith/wood ratio for white wine clones (Feteasca alba 97 St. and Feteasca regala 72 St.) were observed. The biochemical analyses revealed other significant increases of soluble sugars (red wine clones—Feteasca neagra and Cabernet Sauvignon/second year), starch (Feteasca alba and Cabernet Sauvignon in 2021 for both clones), total sugars (Feteasca alba and Feteasca neagra in 2021 for both clones), and of total water content (Feteasca alba and Feteasca neagra in 2021 for both clones), respectively. The applied treatments also led to an increase of young shoots length and grape numbers for all clones as compared to the control (chemical pesticide), which would suggest a potential biostimulant effect of the recipes. [ABSTRACT FROM AUTHOR]

Glass ionomer cements (GICs), restorative materials with commercial availability spanning over five decades, are widely applied due to their advantages (including bio-compatibility, fluoride release, or excellent bonding properties). However, GICs have shortcomings. Among the disadvantages limiting the application of GICs, the poor mechanical properties are the most significant. In order to enhance the mechanical or antimicrobial properties of these materials, the addition of nanomaterials represents a viable approach. The present paper aims to review the literature on the application of different types of nanomaterials for the enhancement of GICs' mechanical and antimicrobial properties, which could lead to several clinical benefits, including better physical properties and the prevention of tooth decay. After applying the described methodology, representative articles published in the time period 2011-present were selected and included in the final review, covering the modification of GICs with metallic nanoparticles (Cu, Ag), metallic and metalloid oxide nanoparticles (TiO2, ZnO, MgO, Al2O3, ZrO2, SiO2), apatitic nanomaterials, and other nanomaterials or multi-component nanocomposites. [ABSTRACT FROM AUTHOR]

With their phytoconstituents acting as reducing and capping agents, natural extracts can be considered a viable alternative for the obtaining of metallic nanoparticles. The properties of phytosynthesized nanoparticles are dependent upon size and morphology, which, in turn, can be tailored by adjusting different parameters of the phytosynthesis process (such as the extracts' composition). In the present study, we aimed to evaluate, for the first time in the literature, the influence of the extraction method and extract concentration on the morphological and biological properties (antioxidant and antibacterial activity) of silver nanoparticles phytosynthesized using Echinacea pupurea L. extracts. The obtained results revealed that the use of the low-concentration Echinacea hydro-alcoholic extract obtained via classical temperature extraction led to the development of nanoparticles with the smallest dimensions (less than 10 nm), compared with the use of extracts obtained with higher concentrations and the extract obtained via the microwave method. The developed nanomaterials exhibited enhanced antioxidant effects (determined via the DPPH assay) and antimicrobial properties (against Escherichia coli and Candida albicans), compared with the parent extracts. [ABSTRACT FROM AUTHOR]

Stones are ones of the most ancient natural materials exploited by humans, with different uses, from tools to buildings, that have endured over time in better conditions than other objects belonging to cultural heritage. Given the importance of those silent witnesses of our past, as well as our duty to preserve all parts of cultural heritage for future generations, much effort was put into the development of materials for their consolidation, protection, self-cleaning, or restoration. Protection of ancient stone monuments and objects has gained the interest of researchers in the last decades in the field of conservation of cultural heritage. In this respect, the present paper aims to be a critical discussion regarding potential polymeric materials, which can be used in restorative and conservative approaches for stone materials of cultural heritage importance, against physical degradation phenomena. Recent advances in this area are presented, as well as the current bottle-necks and future development perspectives. [ABSTRACT FROM AUTHOR]

Over the last few years, new nanoparticle preparation methods have emerged by replacing the usual reagents with plant extracts obtained in different conditions. An example of a natural plant extract is those of cruciferous vegetables, to obtain the new bio-nano-coatings. Given the composition of cruciferous extracts and large amounts of wastes produced all over the world, they can be successful substitutes to replace conventional coatings and extend the possibility of "smart coatings". The present review aims to be a critical discussion regarding the application of cruciferous waste in nanotechnological applications. This review paper can be a starting report for different researchers who intend to use this sustainable approach "from green to nanotechnology" to transpose manufacturing from laboratory to industry. Applying this approach to obtain nanostructures with plant waste highlights the importance of minimizing and re-utilizing residues from primary and secondary processing via chemical and social intervention, in order to contribute to the sustainability needs of the planet and its inhabitants. [ABSTRACT FROM AUTHOR]

This paper aimed to develop two types of support materials with a mesoporous structure of mobile crystalline matter (known in the literature as MCM, namely MCM-41 and MCM-48) and to load them with gallic acid. Soft templating methodology was chosen for the preparation of the mesoporous structures—the cylindrical micelles with certain structural characteristics being formed due to the hydrophilic and hydrophobic intermolecular forces which occur between the molecules of the surfactants (cetyltrimethylammonium bromide—CTAB) when a minimal micellar ionic concentration is reached. These mesoporous supports were loaded with gallic acid using three different types of MCM—gallic acid ratios (1:0.41; 1:0.82 and 1:1.21)—and their characterizations by FTIR, SEM, XRD, BET and drug release were performed. It is worth mentioning that the loading was carried out using a vacuum-assisted methodology: the mesoporous materials are firstly kept under vacuum at ~0.1 barr for 30 min followed by the addition of the polyphenol solutions. The concentration of the solutions was adapted such that the final volume covered the wet mesoporous support and—in this case—upon reaching normal atmospheric pressure, the solution was pushed inside the pores, and thus the polyphenols were mainly loaded inside the pores. Based on the SBET data, it can be seen that the specific surface area decreased considerably with the increasing ratio of gallic acid; the specific surface area decreased 3.07 and 4.25 times for MCM-41 and MCM-48, respectively. The sample with the highest polyphenol content was further evaluated from a biological point of view, alone or in association with amoxicillin administration. As expected, the MCM-41 and MCM-48 were not protective against infections—but, due to the loading of the gallic acid, a potentiated inhibition was recorded for the tested gram-negative bacterial strains. Moreover, it is important to mention that these systems can be efficient solutions for the recovery of the gut microbiota after exposure to antibiotics, for instance. [ABSTRACT FROM AUTHOR]

Analgesics and nonsteroidal anti-inflammatory drugs (NSAIDs) such as paracetamol, diclofenac, and ibuprofen are frequently encountered in surface and ground water, thereby posing a significant risk to aquatic ecosystems. Our study reports the catalytic performances of nanosystems TiO2-MexOy (Me = Ce, Sn) prepared by the sol-gel method and deposited onto glass slides by a dip-coating approach in the removal of paracetamol from aqueous solutions by catalytic ozonation. The effect of catalyst type and operation parameters on oxidation efficiency was assessed. In addition to improving this process, the present work simplifies it by avoiding the difficult step of catalyst separation. It was found that the thin films were capable of removing all pollutants from target compounds to the oxidation products. [ABSTRACT FROM AUTHOR]