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Freshwater contamination by metals can come from a variety of sources and be damaging to wildlife, alter landscapes, and impact human health. Metals removal is desirable not only for improving water quality and preventing adverse effects but also for metals collection and recycling. Nanoadsorption of metals is economically feasible and nanoscale materials exhibit a high surface-area-to-volume ratio that is promising for high adsorption and reactivity. However, the extraordinarily small dimensions of these materials allow them to maneuver biological systems, and combined with high reactivity, this translocation can result in toxicity. In this work, nanoparticles (NPs) composed of a magnetite core coated in hydroxyapatite (HA) and functionalized for adsorption with titanium dioxide (TiHAMNPs) were synthesized. The magnetic core enabled NP retrieval, while HA enhanced adsorption and minimized toxicity. Here, synthesis and characterization are presented, revealing a stable NP structure exhibiting a near neutral surface charge. Results of adsorption studies showed that as compared to silica-coated magnetite nanoparticles (SiMNPs), traditionally used for this application, TiHAMNPs exhibited significantly higher adsorption (43.28% more Cu removal) after 24 h. The equilibrium rate constant for the adsorption of Cu by TiHAMNPs was 0.0003 g/(min*mg) and TiHAMNP adsorption data indicated that TiHAMNPs adsorb metals in a monolayer at the particle surface with a maximum capacity of 2.8 mmol/g. Metabolic and toxicity assays showed TiHAMNPs were highly biocompatible as compared to SiMNPs. This work also explores rare earth element (REE) separation applications of TiHAMNPs, finding that TiHAMNPs may provide a promising alternative for REE retrieval and/or separation. [ABSTRACT FROM AUTHOR]

The necessity for the creation of safe, dependable, biocompatible, and efficient methods to make nanoparticles drives an increasing number of researchers to consider using biological systems as potential eco-friendly nanofactories. Fungi have an innate ability to reduce and oxidize metal ions into metal oxide nanoparticles, thus behaving as nanofactories. In the present study, Trichoderma harzianum was used to prepare ZnO nanoparticles (ZnO NPS). ZnO NPS showed a peak at 370 nm upon testing using UV spectrophotometer and percentages of zinc(72.0±0.2 %) and oxygen(28.0 ±0.3) upon analysis using Edx with an irregular shape, 16.5 nm size and characterized XRD pattern. Soymilk as well as the prepared ZnONPs were investigated either separately or in their mixture (1:1) for their antibacterial and anti-tumor effects. The mixture showed a promising antibacterial impact on Enterococcus faecalis (ATCC29212) and Escherichia coli (ATCC25922) which was confirmed using a transmission electron microscope. ZnONPs mixed with soymilk showed a promising anti-tumor action towards human colorectal adenocarcinoma cell line Caco-2 through boosting apoptotic rate, which was detected by flow cytometry. The current report highlights the possibility of mixing eco-friendly biosynthesized nanoparticles with natural products to enhance their biomedical impact with minimal toxicity as possible innovative pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Nanotechnology has emerged as a promising field in pharmaceutical research, involving producing unique nanoscale materials with sizes up to 100 nm via physiochemical and biological approaches. Nowadays more emphasis has been given to eco-friendly techniques for developing nanomaterials to enhance their biological applications and minimize health and environmental risks. With the help of green nanotechnology, a wide range of green metal, metal oxide, and bimetallic nanoparticles with distinct chemical compositions, sizes, and morphologies have been manufactured which are safe, economical, and environment friendly. Due to their biocompatibility and vast potential in biomedical (antibacterial, anticancer, antiviral, analgesic, anticoagulant, biofilm inhibitory activity) and in other fields such as (nanofertilizers, fermentative, food, and bioethanol production, construction field), green metal nanoparticles have garnered significant interest worldwide. The metal precursors combined with natural extracts such as plants, algae, fungi, and bacteria to get potent novel metal, metal oxide, and bimetallic nanoparticles such as Ag, Au, Co, Cu, Fe, Zr, Zn, Ni, Pt, Mg, Ti, Pd, Cd, Bi2O3, CeO2, Co3O4, CoFe2O4, CuO, Fe2O3, MgO, NiO, TiO2, ZnO, ZrO2, Ag-Au, Ag-Cr, Ag-Cu, Ag-Zn, Ag-CeO2, Ag-CuO, Ag-SeO2, Ag-TiO2, Ag-ZnO, Cu-Ag, Cu-Mg, Cu-Ni, Pd-Pt, Pt-Ag, ZnO-CuO, ZnO-SeO, ZnO-Se, Se-Zr, and Co-Bi2O3. These plant-mediated green nanoparticles possess excellent antibacterial and anticancer activity when tested against several microorganisms and cancer cell lines. Plants contain essential phytoconstituents (polyphenols, flavonoids, terpenoids, glycosides, alkaloids, etc.) compared to other natural sources (bacteria, fungi, and algae) in higher concentration that play a vital role in the development of green metal, metal oxide, and bimetallic nanoparticles because these plant-phytoconstituents act as a reducing, stabilizing, and capping agent and helps in the development of green nanoparticles. After concluding all these findings, this review has been designed for the first time in such a way that it imparts satisfactory knowledge about the antibacterial and anticancer activity of plant-mediated green metal, metal oxide, and bimetallic nanoparticles together, along with antibacterial and anticancer mechanisms. Additionally, it provides information about characterization techniques (UV–vis, FT-IR, DLS, XRD, SEM, TEM, BET, AFM) employed for plant-mediated nanoparticles, biomedical applications, and their role in other industries. Hence, this review provides information about the antibacterial and anticancer activity of various types of plant-mediated green metal, metal oxide, and bimetallic nanoparticles and their versatile application in diverse fields which is not covered in other pieces of literature. [ABSTRACT FROM AUTHOR]

To better understand and utilize the optical reflection behaviors of the nanostructured materials containing small metal nanoparticles (NPs), we once proposed a hypothesis that the recorded characteristic reflection peak should originate from the competition between the localized surface plasmon resonance (LSPR) scattering and absorption of metal NPs. To prove our hypothesis, the Ag- and Au-ion-implanted samples are prepared again by separately introducing 30 keV Ag and Au ions into 0.5-mm-thick SiO2 wafers to a fluence of 6 × 1016 ions/cm2. Especially, the Au-ion-implanted sample is further annealed in flowing nitrogen at different temperatures. Then, using a transmission electron microscope and a fiber spectrometer, all samples' cross-sectional observations and spectral measurements are conducted, respectively. Based on the consistency in peak position and the difference in wavelength range of the absorption and reflection light fields measured from the Ag-ion-implanted sample, the LSPR scattering and absorption of Ag NPs are demonstrated to be coexistent, and their competition are testified to be inevitable and achievable via a filtration process. Besides these indirect evidences for our hypothesis, a direct evidence is also found, which is the blueshift shown by the characteristic reflection peak observed from the rear surface of the Au-ion-implanted sample after annealing. [ABSTRACT FROM AUTHOR]

Highly transparent, conductive nanosheets are extremely attractive for advanced opto-electronic applications. Previously, we have demonstrated that transparent, conductive Au nanosheets can be prepared by UV irradiation of Au nanoparticle (AuNP) monolayers spread on water, which serves as the subphase. However, thick Au nanosheets cannot be fabricated because the method is not applicable to large Au NPs. Further, in order to fabricate nanosheets with different thicknesses and compositions, it is necessary to prepare the appropriate NPs. A strategy is needed to produce nanosheets with different thicknesses and compositions from a single type of metal NP monolayer. In this study, we show that this UV irradiation technique can easily be extended as a nanosheet modification method by using subphases containing metal ions. UV irradiation of 4.7 nm AuNP monolayers on 480 µM HAuCl4 solution increased the thickness of Au nanosheets from 3.5 nm to 36.5 nm, which improved conductivity, but reduced transparency. On the other hand, the use of aqueous AgNO3 and CH3COOAg solutions yielded Au-Ag hybrid nanosheets; however, their morphologies depended on the electrolytes used. In Au-Ag nanosheets prepared on aqueous 500 µM AgNO3, Au and Ag metals are homogeneously distributed throughout the nanosheet. On the other hand, in Au-Ag nanosheets prepared on aqueous 500 µM CH3COOAg, AuNPs still remained and these AuNPs were covered with a Ag nanosheet. Further, these Au-Ag hybrid nanosheets had high conductivity without reduced transparency. Therefore, this UV irradiation method, modified by adding metal ions, is quite effective at improving and diversifying properties of Au nanosheets. [ABSTRACT FROM AUTHOR]

Metal-based nanomaterials (MNMs) have gained particular interest in nanotechnology industry. They are used in various industrial processes, in biomedical applications or to improve functional properties of several consumer products. The widescale use of MNMs in the global consumer market has resulted in increases in the likelihood of exposure and risks to human beings. Human exposure to MNMs and assessment of their potential health effects through the concomitant application of biomarkers of exposure and effect of the most commonly used MNMs were reviewed in this paper. In particular, interactions of MNMs with biological systems and the nanobiomonitoring as a prevention tool to detect the early damage caused by MNMs as well as related topics like the influence of some physicochemical features of MNMs and availability of analytical approaches for MNMs testing in human samples were summarized in this review. The studies collected and discussed seek to increase the current knowledge on the internal dose exposure and health effects of MNMs, highlighting the advantages in using biomarkers in primary prevention and health surveillance. [ABSTRACT FROM AUTHOR]

Organophosphates (OPs) being the most widely used (~ 36%) pesticides, are infamous for presence of their traces in surface waters and serious health hazards to humans and animals. Hence, rapid, efficient, easy to use, and cost-effective methods must be explored for their remediation in contaminated waters. Amongst the different pesticide removal methods, adsorption is extensively used as it is economic unit process which is easy to operate and renders no residual by-product. Moreover, nano-sized adsorbents with novel physico-chemical properties may even be more effectively employed for sorptive removal of OPPs in contaminated waters. The review provides an overview of organophosphate pesticides (OPPs) in terms of usage, environmental contamination, and toxicity. Nanomaterials (e.g., carbon nano-structures, metal nanoparticles and oxides, quantum dots, and metal organic frameworks) categorized into inorganic, organic, and hybrid nanomaterials employed for adsorptive removal of OPPs from aqueous phase have been discussed. The parameters that determine their adsorption efficiency have been discussed, calculated, and compared for different nanostructures. The operating mechanisms behind adsorption of OPPs on nanomaterials are mainly electrostatic interactions, H-bonding, and Π-Π stacking (carbon-based nanomaterials), and exchange or sharing of electrons between vacant active site of nanocomposite and OPP molecules (in case of hybrid materials). Diffusion mechanism and rate-limiting steps have been explored via intra-particle diffusion model. The factors influencing the efficiency of adsorbents such as pH, temperature, adsorbent concentration, and incubation time have also been included. The review further recapitulates the details of thermodynamic studies of adsorption process which give information about the spontaneity and exothermic/endothermic nature of the process. The review concludes with summary and future prospects of sorptive removal of OPPs in water. Adsorption of OPPs onto different nanosorbents via variety of interactions [ABSTRACT FROM AUTHOR]

[Display omitted] • Catalysts have favorable ECSA, multiple active centers, and sufficient mass transport. • PtCo nanoparticles (about 2.5 nm) are uniformly distributed and firmly anchored in the matrix. • The synergistic effect of PtCo, Co 9 S 8 and Co-N strengthens the catalytic performance. • Strong chemical/electronic interactions enhance the anchoring of PtCo NPs on the carrier. • The catalysts exhibit more excellent ORR and HER performance than the Pt/C. The development of low-Pt bifunctional electrocatalysts with excellent performance for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) is critical for the advancement of the hydrogen economy. Here, we have integrated low-loading Pt and Co metals into N, S doped porous carbon nanosheets to obtain composite catalysts encapsulating PtCo alloy nanoparticles (PtCo2@Co 9 S 8 / N -CNS and PtCo2@ N -CNS). The acquired PtCo nanoparticles, with dimensions of about 2.5 nm, are uniformly distributed and firmly anchored in N, S doped carbon nanosheets with large specific surface areas and rich pore structure, forming multiple active centers and effectively preventing the aggregation of metal nanoparticles. The PtCo2@Co 9 S 8 / N -CNS and PtCo2@ N -CNS display high ORR catalytic mass activity of 1.65 A mg Pt -1 and 1.01 A mg Pt -1 in 0.1 M HClO 4. The PtCo2@ N -CNS catalyst exhibits excellent HER performance in 0.5 M H 2 SO 4 , with a mass activity (at 50 mV) 4.3 times higher than that of Pt/C. The PtCo2@Co 9 S 8 / N -CNS and PtCo2@ N -CNS also exhibit stronger ORR and HER stability than Pt/C after accelerated durability tests. The superior catalytic activity performance of catalysts can be attributed to the synergistic effect of multiple active centers of PtCo, Co 9 S 8 and Co-N in the catalysts. The confinement of PtCo nanoparticles by Co metal and N, S doped porous nanosheets derived from graphitic carbon nitride (g-C 3 N 4) as the template, which can effectively prevent the corrosion and migration of the catalysts under acidic conditions, enhances the catalytic stability of the materials. This study provides a new perspective for the development of economical and efficient bifunctional low-Pt catalysts. [ABSTRACT FROM AUTHOR]

Alginate is among the widely applied polysaccharide‐based biomaterial owing to its natural occurrence, chemical versatility, non‐toxicity, environmental friendliness, unique biocompatibility, biodegradability, and mucoadhesive attributes. Nevertheless, it is associated with some demerits, such as inadequate mechanical features and biological activity that hamper broad‐spectrum biomedical scope. Different biopolymeric and nanomaterials have been incorporated into the alginate framework to develop robust nanoplatforms with desired functionalities to overcome this inadequacy. Hybrids of alginate with biopolymers and nanostructured materials improve its mechanical and physicochemical characteristics and may also boost its biological activity. This review aimed to summarize the ongoing progress in alginate‐based nanoplatforms for potential applications in biomedical sectors. Combining alginate with biopolymers (chitosan, starch) and nanostructured materials (silica nanoparticles, graphene oxide nanoparticles, carbon nanotubes/nanorods, and metal oxide nanoparticles) are particularly discussed for drug delivery, wound dressing, tissue engineering, and 3D bioprinting applications. The ongoing challenging facets and futuristic directions on alginate blends are also spotlighted. The alginate‐based hybrids will likely demonstrate biocompatibility, enhanced cell adhesion, cell proliferation, desired mechanical strength, and excellent mineralization. Therefore, they are considered bio‐inspired materials for futuristic biomedical applications. [ABSTRACT FROM AUTHOR]

This editorial discusses the importance of nanoparticles and nanomaterials in various fields such as energy, storage, bioimaging, biosensors, catalysts, nanomedicine, batteries, solar energy, and bioenergy. The special issue presents research on different types of nanoparticles and nanomaterials, including organic, inorganic, polymeric, biomolecules, and bio-nanomaterials. The synthesis and characterization of nanoparticles and nanomaterials are highlighted as crucial for engineering their physicochemical properties. The issue also emphasizes the need to consider and minimize the toxicity and environmental effects of nanoparticles. The editorial concludes by stating that continuous research is necessary to fully realize the potential applications of nanoparticles and nanomaterials in various fields. [Extracted from the article]

[Display omitted] • Caralluma adscendens R.Brown var. bicolor was used for the phytosynthesis of nanomaterials. • Both nanoparticles exhibited greater pharmacological activities. • Prepared nanomaterials were characterized using FTIR, HR-TEM, EDX, and UV–Vis analysis. • Both nanoparticles showed higher wound-healing activity than CABL extract based on the MTT assay and fluorescence analysis. Nanomaterials employed in nanomedicine have the potential to function as both diagnostic and therapeutic tools for individuals. Over the past few decades, significant efforts have been made to synthesize a range of metal nanoparticles through the utilization of different plant extracts. Caralluma adscendens R. Brown var. bicolor leaves (CABL) extract was employed in this study as a reducing/capping agent for the synthesis of gold/silver nanoparticles (CABL@AgNPs/CABL@AuNPs) and explore their pharmacological properties. The successful synthesis of CABL@AgNPs and CABL@AuNPs was confirmed through the observation of surface plasmon resonance (SPR) at 439 and 522 nm using ultraviolet–visible spectrophotometer (UV–Vis). High resolution-transmission electron microscopy (HR-TEM) and energy dispersive X-ray (EDX) techniques were employed to evaluate the shape, size, and chemical composition of the as-synthesized CABL@AgNPs and CABL@AuNPs. Fourier-transform infrared spectroscopy (FTIR) was used to determine the biomolecules responsible for the reduction of metal ions and the stability of metal nanoparticles generated using plant extract. An evaluation was performed to assess the antibacterial and antifungal efficacy of the prepared aqueous CABL extract, CABL@AgNPs, and CABL@AuNPs through the implementation of the disc diffusion technique. The results demonstrated that CABL@AgNPs exhibited greater efficiency when compared to both CABL extract and CABL@AuNPs. The dose-dependent nature of antimicrobial activities was clearly demonstrated through the results of antioxidant and anti-inflammatory experiments. The wound healing activity of the prepared nanomaterials was evaluated using a variety of techniques, including MTT assay, fluorescence staining test, and in vitro scratch assay. The wound-healing capacity of prepared nanomaterials was evaluated using an in vitro scratch assay with Fibroblast L929 cells. The impact of nanoparticles at the IC 50 concentration range was analysed through a fluorescence staining experiment and MTT assay to determine toxicity levels. The environmentally friendly approach of current study shown that both nanoparticles have the potential to be effective therapeutic agents for treating different illnesses. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrospinning is a top-down approach for the fabrication of nanofibers where a viscoelastic fluid is forced through a spinneret during the electrospinning process. • The charges on the droplet work to reduce the surface tension and the electrostatic force tends to converge the droplet forming a cone. • Electrospinning of various CPs have shown to enhance several parameters such as higher surface area allows better immobilization of the biorecognition element and higher mass transport. • Only few polymers have been successfully developed into nanofibers as the formation of Taylor cone contributes to the variability in diameter of the nanofiber. Electrospinning is an affordable and flexible technique used to create intricate nanofibrous structures from different polymers. These highly adaptable electrospun nanofibers are used in many different domains, including biosensing, implants, tissue engineering as well as in drug and gene delivery. In biosensing, electrospun nanofibers offer several advantages like high surface area for the attachment of biomolecules, improving the sensitivity and effectiveness of analyte detection. Incorporating conducting polymers and metal nanoparticles into these nanofibers has become a common practice. This combination forms nano bio-composites with improved conductivity and stability, which are crucial for the development of accurate biosensing devices. Several biosensor platforms use electrospun nanofibers, including lab-on-a-chip devices, ELISA-style bioassays and point-of-care diagnostics. By adjusting the size, form, and content of the nanofibers, scientists can enhance the performance of biosensors, allowing for the label-free and real-time detection of target molecules. Moreover, electrospinning enables the creation of conductive polymer layers on biosensing electrodes, ensuring secure anchoring of receptors and facilitating electron transfer. This method offers benefits like improved conductivity, compatibility with living tissue, and long-lasting stability, contributing to the advancement of electrochemical biosensors. Recent breakthroughs in nanostructured conducting polymer electrospun materials have revolutionized the field of electrochemical biosensors. The paper highlights the remarkable composites that considerably improve biomarker sensing capabilities of several polymer types, including the polypyrrole polythiophene, polyaniline, poly (3,4-ethylene dioxythiophene)-poly (styrene sulfonate), and polycarbazole. This article emphasizes the use of electrospinning to develop nanostructured materials, showcasing advancements in electrochemical biosensors. [ABSTRACT FROM AUTHOR]

The metal/organic hybrid nanomaterials for cancer theranostics. [Display omitted] • The recent advances in metal nanocomposites (metal/organic hybrid nanomaterials) for cancer imaging are briefly summarized. • The application of metal/organic hybrid nanomaterials in different therapeutic methods is systematically reviewed. • The development prospects of metal/organic hybrid nanomaterials for cancer theranostics are briefly discussed. Cancer is an extremely significant disease that profoundly impacts human survival and quality of life. Researchers have been searching for effective therapies, among which metal/organic hybrid nanomaterials received widespread attention due to their tumor imaging and treatment capabilities. Metal/organic hybrid nanomaterials are easy to modify and possess magnetic and plasma resonance, catalytic function, and biological activity. Then, researchers have recently designed a series of highly efficient metal/organic hybrid nanomaterials with integrated theranostics, good biocompatibility, and relative safety for achieving excellent therapeutic outcomes in cancer combined with various treatment methods. This paper highlights the research progress of metal/organic hybrid nanomaterials in the single diagnosis and treatment of cancer and their integration into diagnosis and treatment. The development trends, key problems, future outlook, and challenges of metal/organic hybrid nanomaterials are summarized and discussed. It is expected that the metal nanoparticles discussed in this paper can provide insights into the early diagnosis and effective treatment of cancer. [ABSTRACT FROM AUTHOR]

Nanomaterial integration in building materials has become a pivotal approach to provide cementitious composites with dual functionality, namely photocatalytic and antimicrobial attributes, conferring self-cleaning and anti-polluting characteristics to these materials. We conducted a systematic literature review on the photocatalytic and antimicrobial properties of ZnO-NP in construction materials, selecting all articles from the last 5 years. We performed a search on the Web of Science and 25 articles were selected consistent with the study purpose, after the filtration process aligned with PRISMA guidelines. This is the first article on this topic using a methodological review, covering all recent literature and the most cited articles from recent decades. Although the volume of articles is still limited, it was possible to identify the most efficient percentages of ZnO-NP in different construction materials (paint, mortar, concrete, wood, others). The main applications, challenges, and themes for future research are discussed to produce safer and more sustainable materials and with potential to be used in the civil construction industry. [Display omitted] • Application of ZnO-NP in building materials is reviewed. • Antimicrobial and photocatalytic potential was summarized. • ZnO-NP helps to creation of building materials that provide safer environments. • This paper aims to encourage and promote the use of ZnO-NP in building materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanomaterials possess exceptional optoelectric and electromagnetic properties due to their small size and large surface area • Nanomaterials have been extensively utilized in the biomedical and bioengineering fields, ranging from diagnostics to therapeutics. • Surface modifications of nanomaterials are essential to enhance their adsorbing capability for biomarkers on the nanomaterial surface. • The study explores surface modifications of diverse nanomaterials, encompassing metallic nanoparticles, carbon-based nanomaterials, and self-assembled materials. • The emphasis of the paper is on different surface modification techniques to improve the functionality and applicability of nanomaterials in medical diagnosis. Ranging from diagnostics to therapeutics, nanomaterials have been widely exploited in the fields of biomedicine and bioengineering. The past few decades have witnessed the development of a number of nanomaterials for bringing out the best results in the field of medical diagnosis. However, despite possessing extremely unique material properties, many of them lack surface heterogenic reactivity, which is a crucial factor for the specific binding of biomarkers on the nanomaterial surface. For this reason, nanomaterials have to undergo surface modifications so as to increase the adsorbing capability of biomarkers over the functionalized nanomaterial surface. Keeping in mind the importance of surface modification for successful application of nanomaterials in medical diagnosis, different surface modifications of a number of nanomaterials like metallic nanoparticles (metal and metal oxide nanoparticles, binary compounds), carbon-based nanomaterials (graphene-based nanomaterials, carbon dots, carbon nanotubes), and self-assembled materials have been discussed in this paper. Different types of interactions, such as covalent and non-covalent forces such as electrostatic force, hydrogen bonds, and Vander Waals, have been reported in the literature, which lead to the functionalization of nanoparticles. It has been found that organic molecules such as phosphates, citrates, thiols, amines, and various polymer molecules such as dextran, chitosan, PEG, etc. and inorganic compounds such as metallic elements and ligands are significant in the surface functionalization process of freshly synthesized nanoparticles. The self-assembly of nanostructures has also been found to be beneficial in terms of compatibility in biological media and to be a promising technique for biosensing-related applications of these nanostructures. This study aims at throwing light on the technology prevalent in the field of making nanostructures more advantageous in the field of biosensing by functionalizing their surface, and it indicates that by collaborating nanotechnology with different disciplines such as chemistry, biology, physics, and medicine, it will emerge as the most preferred and commercialized platform for biomedical functions such as biosensing, bioengineering, gene therapy, drug delivery, etc. [ABSTRACT FROM AUTHOR]