Efficient remediation of different concentrations of Cr-contaminated soils by nano zero-valent iron modified with carboxymethyl cellulose and biochar.

Nano zero-valent iron (nZVI) is widely used in soil remediation due to its high reactivity. However, the easy agglomeration, poor antioxidant ability and passivation layer of Fe-Cr coprecipitates of nZVI have limited its application scale in Cr-contaminated soil remediation, especially in high concentration of Cr-contaminated soil. Herein, we found that the carboxymethyl cellulose on nZVI particles could increase the zeta potential value of soil and change the phase of nZVI. Along with the presence of biochar, 97.0% and 96.6% Cr immobilization efficiency through CMC-nZVI/BC were respectively achieved in high and low concentrations of Cr-contaminated soils after 90-days remediation. In addition, the immobilization efficiency of Cr(VI) only decreased by 5.1% through CMC-nZVI/BC treatment after 10 weeks aging in air, attributing to the strong antioxidation ability. As for the surrounding Cr-contaminated groundwater, the Cr(VI) removal capacity of CMC-nZVI/BC was evaluated under different reaction conditions through column experiments and COMSOL Multiphysics. CMC-nZVI/BC could efficiently remove 85% of Cr(VI) in about 400 hr when the initial Cr(VI) concentration was 40 mg/L and the flow rate was 0.5 mL/min. This study demonstrates that uniformly dispersed CMC-nZVI/BC has an excellent remediation effect on different concentrations of Cr-contaminated soils.

A highly sensitive electrochemical sensor based on poly(3-aminobenzoic acid)/graphene oxide-gold nanoparticles modified screen printed carbon electrode for paraquat detection.

Herein, a modified screen printed carbon electrode (SPCE) based on a composite material, graphene oxide-gold nanoparticles (GO-AuNPs), and poly(3-aminobenzoic acid)(P3ABA) for the detection of paraquat (PQ) is introduced. The modified electrode was fabricated by drop casting of the GO-AuNPs, followed by electropolymerization of 3-aminobenzoic acid to achieve SPCE/GO-AuNPs/P3ABA. The morphology and microstructural characteristics of the modified electrodes were revealed by scanning electron microscopy (SEM) for each step of modification. The composite GO-AuNPs can provide high surface area and enhance electroconductivity of the electrode. In addition, the presence of negatively charged P3ABA notably improved PQ adsorption and electron transfer rate, which stimulate redox reaction on the modified electrode, thus improving the sensitivity of PQ analysis. The SPCE/GO-AuNPs/P3ABA offered a wide linear range of PQ determination (10-9-10-4 mol/L) and low limit of detection (LOD) of 0.45 × 10-9 mol/L or 0.116 µg/L, which is far below international safety regulations. The modified electrode showed minimum interference effect with percent recovery ranging from 96.5% to 116.1% after addition of other herbicides, pesticides, metal ions, and additives. The stability of the SPCE/GO-AuNPs/P3ABA was evaluated, and the results indicated negligible changes in the detection signal over 9 weeks. Moreover, this modified electrode was successfully implemented for PQ analysis in both natural and tapped water with high accuracy.

Cotransport of nanoplastics with nZnO in saturated porous media: From brackish water to seawater.

The ocean serves as a repository for various types of artificial nanoparticles. Nanoplastics (NPs) and nano zinc oxide (nZnO), which are frequently employed in personal care products and food packaging materials, are likely simultaneously released and eventually into the ocean with surface runoff. Therefore, their mutual influence and shared destiny in marine environment cannot be ignored. This study examined how nanomaterials interacted and transported through sea sand in various salinity conditions. Results showed that NPs remained dispersed in brine, while nZnO formed homoaggregates. In seawater of 35 practical salinity units (PSU), nZnO formed heteroaggregates with NPs, inhibiting NPs mobility and decreasing the recovered mass percentage (Meff) from 24.52% to 12.65%. In 3.5 PSU brackish water, nZnO did not significantly aggregate with NPs, and thus barely affected their mobility. However, NPs greatly enhanced nZnO transport with Meff increasing from 14.20% to 25.08%, attributed to the carrier effect of higher mobility NPs. Cotransport from brackish water to seawater was simulated in salinity change experiments and revealed a critical salinity threshold of 10.4 PSU, below which the mobility of NPs was not affected by coexisting nZnO and above which nZnO strongly inhibited NP transport. This study highlights the importance of considering the mutual influence and shared destiny of artificial nanoparticles in the marine environment and how their interaction and cotransport are dependent on changes in seawater salinity.

Catalytic detoxification of mitoxantrone by graphitic carbon nitride (g-C3N4) supported Fe/Pd bimetallic nanoparticles.

The overuse of antibiotics and antitumor drugs has resulted in more and more extensive pollution of water bodies with organic drugs, causing detrimental ecological effects, which have attracted attention towards effective and sustainable methods for antibiotics and antitumor drug degradation. Here, the hybrid nanomaterial (g-C3N4@Fe/Pd) was synthesized and used to remove a kind of both an antibiotic and antitumor drug named mitoxantrone (MTX) with 92.0% removal efficiency, and the MTX removal capacity is 450 mg/g. After exposing to the hybrid material the MTX aqueous solution changed color from dark blue to lighter progressively, and LC-UV results of residual solutions show that a new peak at 3.0 min (MTX: 13.2 min) after removal by g-C3N4@Fe/Pd appears, with the simultaneous detection of intermediate products indicating that g-C3N4@Fe/Pd indeed degrades MTX. Detailed mass spectrometric analysis suggests that the nuclear mass ratio decreased from 445.2 (M+1H) to 126.0 (M+1H), 169.1 (M+1H), 239.2 (M+1H), 267.3 (M+1H), 285.2 (M+1H), 371.4 (M+1H) and 415.2 (M+1H), and the maximum proportion (5.63%) substance of all degradation products (126.0 (M+1H)) is 40-100 times less toxic than MTX. A mechanism for the removal and degradation of mitoxantrone was proposed. Besides, actual water experiments confirmed that the maximum removal capacity of MTX by g-C3N4@Fe/Pd is up to 492.4 mg/g (0.02 g/L, 10 ppm).

Integrating Pt nanoparticles with 3D Cu2- x Se/GO nanostructure to achieve nir-enhanced peroxidizing Nano-enzymes for dynamic monitoring the level of H2O2 during the inflammation.

The treatment of wound inflammation is intricately linked to the concentration of reactive oxygen species (ROS) in the wound microenvironment. Among these ROS, H2O2 serves as a critical signaling molecule and second messenger, necessitating the urgent need for its rapid real-time quantitative detection, as well as effective clearance, in the pursuit of effective wound inflammation treatment. Here, we exploited a sophisticated 3D Cu2- x Se/GO nanostructure-based nanonzymatic H2O2 electrochemical sensor, which is further decorated with evenly distributed Pt nanoparticles (Pt NPs) through electrodeposition. The obtained Cu2- x Se/GO@Pt/SPCE sensing electrode possesses a remarkable increase in specific surface derived from the three-dimensional surface constructed by GO nanosheets. Moreover, the localized surface plasma effect of the Cu2- x Se nanospheres enhances the separation of photogenerated electron-hole pairs between the interface of the Cu2- x Se NPs and the Pt NPs. This innovation enables near-infrared light-enhanced catalysis, significantly reducing the detection limit of the Cu2- x Se/GO@Pt/SPCE sensing electrode for H2O2 (from 1.45 µM to 0.53µM) under NIR light. Furthermore, this biosensor electrode enables in-situ real-time monitoring of H2O2 released by cells. The NIR-enhanced Cu2- x Se/GO@Pt/SPCE sensing electrode provide a simple-yet-effective method to achieve a detection of ROS (H2O2、-OH) with high sensitivity and efficiency. This innovation promises to revolutionize the field of wound inflammation treatment by providing clinicians with a powerful tool for accurate and rapid assessment of ROS levels, ultimately leading to improved patient outcomes.

Ferula latisecta gels for synthesis of zinc/silver binary nanoparticles: antibacterial effects against gram-negative and gram-positive bacteria and physicochemical characteristics.

This study explores the potential antibacterial applications of zinc oxide nanoparticles (ZnO NPs) enhanced with silver (Ag) using plant gel (ZnO-AgO NPs). The problem addressed is the increasing prevalence of pathogenic bacteria and the need for new, effective antimicrobial agents. ZnO NPs possess distinctive physicochemical properties that enable them to selectively target bacterial cells. Their small size and high surface area-to-volume ratio allow efficient cellular uptake and interaction with bacterial cells. In this study, the average size of the synthesized ZnO-Ag nanoparticles was 77.1 nm, with a significant standard deviation of 33.7 nm, indicating a wide size distribution. The nanoparticles demonstrated remarkable antibacterial efficacy against gram-negative and gram-positive bacteria, with inhibition zones of 14.33 mm for E. coli and 15.66 mm for B. subtilis at a concentration of 300 µg/ml. Minimum inhibitory concentrations (MIC) were determined to be 100 µg/ml for E. coli and 75 µg/ml for S. saprophyticus. Additionally, ZnO-Ag NPs exhibited excellent biocompatibility, making them appropriate for various pharmacological uses. This study utilizes Ferula latisecta gels, offering a sustainable and eco-friendly approach to nanoparticle synthesis. Incorporating of Ag into ZnO NPs significantly enhances their antimicrobial properties, with the combined results showing great inhibition effects on pathogenic microbes. The findings suggest that ZnO-Ag NPs could be a promising candidate for addressing the challenges posed by drug-resistant bacterial infections and enhancing antimicrobial treatments.

Solid electrochemiluminescence sensor by immobilization luminol in Zn-Co-ZIF CNFs for sensitive detection of procymidone in vegetables.

A solid-state electrochemiluminescence (ECL) sensor was fabricated by immobilizing luminol, a classical luminescent reagent, on a Zn-Co-ZIF carbon fiber-modified electrode for the rapid and sensitive detection of procymidone (PCM) in vegetable samples. The sensor was created by sequentially modifying the glassy carbon electrode with Zn-Co-ZIF carbon fiber (Zn-Co-ZIF CNFs), Pt@Au NPs, and luminol. Zn-Co-ZIF CNFs, prepared through electrospinning and high-temperature pyrolysis, possessed a large specific surface area and porosity, making it suitable as carrier and electron transfer accelerator in the system. Pt@Au NPs demonstrated excellent catalytic activity, effectively enhancing the generation of active substances. The ECL signal was significantly amplified by the combination of Zn-Co-ZIF CNFs and Pt@Au NPs, which can subsequently be diminished by procymidone. The ECL intensity decreased proportionally with the addition of procymidone, displaying a linear relationship within the concentration range 1.0 × 10-13 to 1.0 × 10-6 mol L-1 (R2 = 0.993). The sensor exhibited a detection limit of 3.3 × 10-14 mol L-1 (S/N = 3) and demonstrated outstanding reproducibility and stability, making it well-suited for the detection of procymidone in vegetable samples.

A sequential dual-locked luminescent copper nanocluster probe for tumor cell imaging and killing.

A sequential dual-locked luminescent copper nanoclusters (CuNCs) probe was designed and synthesized for the specific imaging and selective killing of tumor cells. This nanoprobe was prepared by first forming a Fe3+-coupled tannic acid (TA)-stabilized CuNCs (CuNCs-FeIII), which is in quenching state due to the electron transfer between CuNCs and Fe3+, and then coating a protectable layer of hyaluronic acid (HA) on the surface of CuNCs-FeIII to form the final dual-locked nanoprobe (CuNCs-FeIII@HA). When the nanoprobe of CuNCs-FeIII@HA target enter the tumor cells through CD44-HA receptor, HAase will first digest the HA layer of the nanoprobes, and then, GSH over-expressed in tumor cells will reduce Fe3+ to Fe2+, thus restoring the fluorescence emission of CuNCs and at the same time killing the tumor cells with the hydroxyl free radicals (∙OH) produced by the Fenton reaction between Fe2+ and H2O2. This sequential dual-locked luminescent nanoprobe of CuNCs-FeIII@HA has been successfully used for the specific imaging and selective killing of tumor cells.

Low-dose zinc oxide nanoparticles trigger the growth and biofilm formation of Pseudomonas aeruginosa: a hormetic response.

INTRODUCTION: Hormesis describes an inverse dose-response relationship, whereby a high dose of a toxic compound is inhibitory, and a low dose is stimulatory. This study explores the hormetic response of low concentrations of zinc oxide nanoparticles (ZnO NPs) toward Pseudomonas aeruginosa. METHOD: Samples of P. aeruginosa, i.e. the reference strain, ATCC 27,853, together with six strains recovered from patients with cystic fibrosis, were exposed to ten decreasing ZnO NPs doses (0.78-400 µg/mL). The ZnO NPs were manufactured from Peganum harmala using a chemical green synthesis approach, and their properties were verified utilizing X-ray diffraction and scanning electron microscopy. A microtiter plate technique was employed to investigate the impact of ZnO NPs on the growth, biofilm formation and metabolic activity of P. aeruginosa. Real-time polymerase chain reactions were performed to determine the effect of ZnO NPs on the expression of seven biofilm-encoding genes. RESULT: The ZnO NPs demonstrated concentration-dependent bactericidal and antibiofilm efficiency at concentrations of 100-400 µg/mL. However, growth was significantly stimulated at ZnO NPs concentration of 25 µg/mL (ATCC 27853, Pa 3 and Pa 4) and at 12.5 µg/mL and 6.25 µg/mL (ATCC 27853, Pa 2, Pa 4 and Pa 5). No significant positive growth was detected at dilutions < 6.25 µg/mL. similarly, biofilm formation was stimulated at concentration of 12.5 µg/mL (ATCC 27853 and Pa 1) and at 6.25 µg/mL (Pa 4). At concentration of 12.5 µg/mL, ZnO NPs upregulated the expression of LasB ( ATCC 27853, Pa 1 and Pa 4) and LasR and LasI (ATCC 27853 and Pa 1) as well as RhII expression (ATCC 27853, Pa 2 and Pa 4). CONCLUSION: When exposed to low ZnO NPs concentrations, P. aeruginosa behaves in a hormetic manner, undergoing positive growth and biofilm formation. These results highlight the importance of understanding the response of P. aeruginosa following exposure to low ZnO NPs concentrations.

Antioxidant evaluation study of black rice anthocyanins nano-composite as prospective against infertility induced by AlCl3 in rats.

Anthocyanins are known as an antioxidant, and their water-soluble purple-colored pigments are very nutritive. Therefore, the present study investigated the antioxidant activity of black rice anthocyanins nano-composite against infertility induced by AlCl3 in rats. Anthocyanin silver nanoparticles (An-AgNPs) were prepared by reducing black rice anthocyanin with the metallic ions. Antioxidant activity (DPPH %) of anthocyanin was determined. Also, the morphology of (An-AgNPs) was examined by scanning electron microscopy (SEM). Albino rats were divided into five groups (negative control (NC): fed on basel diet, positive control (PC): treated with AlCl3 (34 mg/kg bw) for seventy days, and three other groups treated with AlCl3 (34 mg/kg bw) + An-AgNPs at 10, 15, and 20 mg/kg, b.w/ day, respectively for seventy days. Serum testosterone, LH, FSH, and estradiol were measured. Additionally, Sperm motility, Sperm count (Testicular and Epididymal), fructose in semen, and semen quality were determined. The values of the anthocyanin component and DPPH radical scavenging activity obtained were 3603.82±6.11 mg CCE/g and 84.62±1.98, respectively. An-AgNPs shows tend to agglomerate, particles are uniform in size and shape, and the diameter of the particles ranges between 70nm to 130nm. LH, estradiol and testosterone levels increased significantly in rats treated with An-AgNPs 10, 15, 20 mg/kg b.w+ AlCl3 (34 mg/kg bw) also exhibited significantly higher sperm motility, sperm count, and daily sperm production, and decreased sperm transit rate than G2. In comparison to G2, animals treated with AlCl3 (34 mg/kg bw) + An-AgNPs 10, 15, 20 mg/kg b.w(G3 to G5) had significantly higher semen and semen quality (P 0.05). We can conclude that the An-AgNPs showed a strong effect against infertility induced by AlCl3; this represents a suitable natural supply of biological substances for medicine and anthocyanins could be considered the ideal ingredients against oxidative stress-induced infertility.

Antifungal properties and molecular docking of ZnO NPs mediated using medicinal plant extracts.

Significant postharvest losses and food safety issues persist in many developing nations, primarily due to fungal activities, including mycotoxin production. In this study, green synthesised zinc oxide nanoparticles (ZnO-NPs) were prepared from leaf extracts of Syzygium cordatum (ZnO 1), Lippia javanica (ZnO 2), Bidens pilosa (ZnO 3), and Ximenia caffra (ZnO 4). Physicochemical characteristics of the ZnO-NPs were determined using X-ray diffraction (XRD), Fourier transmission Infrared spectroscopy and ultraviolet-visible (UV-vis) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The XRD analysis confirmed the presence of a wurtzite crystal structure in the hexagonal shape of the ZnO nanoparticles (NPs), with an average size ranging between 25 and 43 nm. The microscopic examination of the morphology revealed the presence of spherical particles with sizes ranging from 37 to 47 nm in diameter. The antifungal efficacy of the ZnO-NPs was assessed against pathogenic plant fungi, including Botrytis sp. (STEU 7866), Penicillium sp. (STEU 7865), and Pilidiella granati (STEU 7864), using the poisoned food technique. Further antifungal evaluation of the ZnOPs was performed using the broth microdilution assay. A significant interaction between the type of ZnO-NPs and fungal species was observed, with the highest susceptibility in Mucor sp. to ZnO 2, achieving over 50% inhibition. Penicillium sp. also showed high susceptibility to all ZnO-NPs. Molecular docking results confirmed the strong H-bonding interactions of ZnO-NPs with fungal receptors in Mucor sp. and Penicillium sp., Botrytis sp. and P. granati exhibited the least susceptibility. Further tests revealed that ZnO 2 exhibited the highest inhibitory effect on Botrytis sp., with a low minimum inhibitory concentration (MIC) of 25 µg/mL, attributed to its larger positive zeta potential. This study indicates that ZnO NPs, particularly those mediated using Lippia javanica (ZnO 2), have promising potential as effective antifungal agents, which could play a significant role in reducing postharvest decay and losses.

Antibiotic Nanoparticles-Loaded Wound Dressings Against Pseudomonas aeruginosa's Skin Infection: A Systematic Review.

Pseudomonas aeruginosa (P. aeruginosa) is a common nosocomial pathogen that can cause severe infections in critically ill patients. Due to its resistance to multiple drugs, it is challenging to treat, which can result in serious illness and death. Conventional treatments for infected wounds often involve the topical or systemic application of antibiotics, which can lead to systemic toxicity and the development of drug resistance. The combination of wound dressings that promote wound healing with nanoparticles (NPs) represents a revolutionary strategy for optimizing the safety and efficacy of antibiotics. This review assesses a systematic search to identify the latest approaches where the evaluation of wound dressings loaded with antibiotic NPs is conducted. The properties of NPs, the features of wound dressings, the antimicrobial activity and biocompatibility of the different strategies are analyzed. The results indicate that most research in this field is focused on dressings loaded with silver NPs (57.1%) or other inorganic materials (22.4%). Wound dressings loaded with polymeric NPs and carbon-based NPs represent 14.3% and 6.1% of the evaluated studies, respectively. Nevertheless, there are no clinical trials that have evaluated the efficacy of NPs-loaded wound dressings in patients. Further research is required to ensure the safety of these treatments and to translate the findings from the bench to the bedside.

Synthesis of novel polyethyleneimine-capped silver nanoclusters exhibiting ultraviolet-A fluorescence and their application in multiple sensing.

Cupric ions (Cu2+), pyrophosphate (PPi), and alkaline phosphatase (ALP) are involved in a variety of biochemical processes such as DNA replication, cellular metabolism and play an important role in human growth and development. It is of great significance to establish a method for the sensitive detection of Cu2+, PPi and ALP. In this work, polyethyleneimine-capped silver nanoclusters (PEI-AgNCs) were successfully synthesized by a one-pot method using hydrazine sulfate as reductant, exhibiting a unique strong fluorescence emission in the near-ultraviolet region at ∼339 nm. Since the fluorescence of PEI-AgNCs can be quenched by Cu2+ through inner filtering effect (IFE), then recovered by competitive binding of pyrophosphate and Cu2+, and later weakened again by catalytic hydrolysis of alkaline phosphatase, a sensitive and selective strategy based on the changes of fluorescence "ON" or "OFF" was established to detect Cu2+, PPi and ALP. The LODs of these three analytes were 36 nM, 0.2 µM, and 0.14 U L-1 at a S/N ratio of 3, respectively. A series of logic gate circuits for sensing cupric ions, pyrophosphate, and alkaline phosphatase were successfully constructed. The established methods have the potential for biosensing and environmental analysis and the specific UV-A fluorescence property of PEI-AgNCs may be helpful in photonic and optical areas.

Design of silver nanoparticle-embedded nano zirconium-based metal-organic frameworks for highly sensitive detection of chlorpyrifos in real samples.

Chlorpyrifos (CPS) is widely found in food and water sources due to agricultural use, posing health and environmental risks. Therefore, this work introduces a fluorescent sensor design of silver nanoparticle-embedded nano zirconium-based metal-organic frameworks (UiO-66-NH2@AgNPs) for accurate examination of CPS. Briefly, UiO-66-NH2 was synthesized hydrothermally, exhibiting weak luminescence owed to ligand-to-metal charge transfer (LMCT). Here, it limits its direct utility in fluorescence-based detection. To address this limitation, silver nanoparticles (AgNPs) were introduced into UiO-66-NH2, enhancing fluorescence via the metal-enhanced fluorescence (MEF) effect. Briefly, a comprehensive spectral analysis such as XPS, SEM, TEM, PXRD, etc., was performed to validate the synthesis of UiO-66-NH2@AgNPs. Subsequent evaluation revealed that CPS effectively quenched the luminescence intensity of UiO-66-NH2@AgNPs through a static quenching mechanism. The fluorescence intensity exhibited good linearity with CPS concentration in the span of 10 to 1,000 ng/mL, with a recognition limit of 191.5 ng/mL(S/N = 3). The interaction involved Ag-S bond formation and electrostatic interactions, reducing fluorescence intensity. The method was confirmed through successful CPS detection in fruit samples. The UiO-66-NH2@AgNPs nanoprobe offers a simple, sensitive, and accurate platform for CPS sensing, with potential for future use in detecting CPS in fruits and vegetables.

Plasmonic nanophotothermal therapy: Destruction of 500 mm3 subcutaneous human basal cell carcinoma with gold nanoparticles and near infrared laser.

SIGNIFICANCE: Multilesional basal cell carcinoma (BCC) are spread on sun exposed skin areas, including arms, face and back. The first-line treatment remains the surgical resection or Mohs surgery. Despite its high complexity, Mohs surgery is well practiced in USA and Germany and presents very good results both in esthetic and in carcinology point of view. Large lesions more than 2 cm remain challenging to remove by topical cream used in photodynamic therapy (PDT). If these larger lesions are not treated in less than 1 month, they could grow deeply in the skin, thus enhancing the risk of reoccurrence and the severity of the disease. Despite this model herein studied, that is non melanoma skin cancer is a good prognostic cancer, the therapy aims to be applied to more aggressive melanoma skin cancers. AIM: Total regression of large cutaneous lesions less than 1 month with no reoccurrence. APPROACH: Tumor induction on murine model bearing a 500 mm3 subcutaneous lesion. Increasing dose of gold nanoparticles at fixed initial concentration C0 = 0.3 mg/mL, infused into the tumor then exposition of the region of interest to NIR medical laser to assess the therapy. One or two intratumoral administration(s) were compared to surgery and control, that is no treatment, laser alone or nanoparticles alone. RESULTS: Gold nanoparticles alone or the NIR laser alone did not induce the tumor regression. The combination of laser and nanoparticles called plasmonic nanophotothermal therapy induced apoptosis. Derma and hypoderm do not show any visible gold nanoparticles and demonstrated a good cicatrization process. CONCLUSION: Plasmonic nanophotothermal therapy using two doses of gold nanoparticles was the only protocol that proved its efficacy on large lesions in 14 days, that is 500 mm3 on a murine model bearing human basal cell carcinoma.

Biosynthesis and Characterization of Aeonium arboreum-Derived Silver Nanoparticles: Antimicrobial Activity, Biofilm Inhibition, Antihemolytic Activity, and In Silico Studies.

Environmentally friendly biosynthesis of silver nanoparticles (AgNPs) from Aeonium arboreum (L.) Webb & Berthel is reported for the first time. The synthesized AgNPs were characterized using UV-Vis, FTIR, TEM, Zeta potential, and XRD analysis, revealing high stability (-29.1 mV), spherical shape, and an average size of 100 nm. The antimicrobial activity levels of both A. arboreum extract and biosynthesized AgNPs were evaluated against five uropathogens (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans). Both the extract and the AgNPs exhibited significant efficacy, particularly against E. coli, with inhibition zones of 27 mm and 30 mm, respectively. LC-MS analysis tentatively identified 11 secondary metabolites in the extract, including quercetin-3-O-glucoside, quercetin-3-O-rhamnoside, myricetin 3-glucoside, and daphneresinol. In silico docking studies revealed promising binding affinities of these metabolites in relation to key enzymes involved in bacterial folate synthesis (dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS)) and DNA replication (DNA gyrase). These findings demonstrate the potential of A. arboreum-based AgNPs and their associated metabolites as a novel therapeutic approach for combating urinary tract infections. Their antimicrobial, antihemolytic, and antibiofilm properties warrant further investigation.

Biosynthesized silver nanoparticles mediated by Ammi visnaga extract enhanced systemic resistance and triggered multiple defense-related genes, including SbWRKY transcription factors, against tobacco mosaic virus infection.

BACKGROUND: Tobacco mosaic virus (TMV) is a highly infectious plant virus that affects a wide variety of plants and reduces crop yields around the world. Here, we assessed the effectiveness of using Ammi visnaga aqueous seed extract to synthesize silver nanoparticles (Ag-NPs) and their potential to combat TMV. Different techniques were used to characterize Ag-NPs, such as scanning and transmission electron microscopy (SEM, TEM), energy-dispersive X-ray spectroscopy (EDS), fourier transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS). RESULTS: TEM demonstrated that the synthesized Ag-NPs had a spherical form with an average size of 23-30 nm and a zeta potential value of -15.9 mV, while FTIR revealed various functional groups involved in Ag-NP stability and capping. Interestingly, the Pre-treatment of tobacco plants (protective treatment) with Ag-NPs at 100-500 µg/mL significantly suppressed viral symptoms, while the Post-treatment (curative treatment) delayed their appearance. Furthermore, protective and curative treatments significantly increased chlorophyll a and b, total flavonoids, total soluble carbohydrates, and antioxidant enzymes activity (PPO, POX and CAT). Simultaneously, the application of Ag-NPs resulted in a decrease in levels of oxidative stress markers (H2O2 and MDA). The RT-qPCR results and volcano plot analysis showed that the Ag-NPs treatments trigger and regulate the transcription of ten defense-related genes (SbWRKY-1, SbWRKY-2, JERF-3, GST-1, POD, PR-1, PR-2, PR-12, PAL-1, and HQT-1). The heatmap revealed that GST-1, the primary gene involved in anthocyanidin production, was consistently the most expressed gene across all treatments throughout the study. Analysis of the gene co-expression network revealed that SbWRKY-19 was the most central gene among the studied genes, followed by PR-12 and PR-2. CONCLUSIONS: Overall, the reported antiviral properties (protective and/or curative) of biosynthesized Ag-NPs against TMV lead us to recommend using Ag-NPs as a simple, stable, and eco-friendly agent in developing pest management programs against plant viral infections.

Biocompatibility and potential anticancer activity of gadolinium oxide (Gd2O3) nanoparticles against nasal squamous cell carcinoma.

Chemotherapy as a cornerstone of cancer treatment is slowly being edged aside owing to its severe side effects and systemic toxicity. In this case, nanomedicine has emerged as an effective tool to address these drawbacks. Herein, a biocompatible carrier based on bovine serum albumin (BSA) coated gadolinium oxide nanoparticles (Gd2O3@BSA) was fabricated for curcumin (CUR) delivery and its physicochemical features along with its potential anticancer activity against nasal squamous cell carcinoma were also investigated. It was found that the fabricated Gd2O3@BSA containing CUR (Gd2O3@BSA-CUR) had spherical morphology with hydrodynamic size of nearly 26 nm, zeta-potential of -36 mV and high drug (CUR) loading capacity. Drug release profile disclosed that the release of CUR from the prepared Gd2O3@BSA-CUR nanoparticles occurred in a sustained- and pH-dependent manner. Also, in vitro cytotoxicity analysis revealed that the fabricated Gd2O3@BSA nanoparticles possessed excellent biosafety toward HFF2 normal cells, while Gd2O3@BSA-CUR appeared to display the greatest anticancer potential against RPMI 2650 and CNE-1 cancer cell lines. The results also show that the Gd2O3@BSA nanoparticles were compatible with the blood cells with minor hemolytic effect (< 3%). The manufactured NPs were found to be completely safe for biological applications in an in vivo subacute toxicity study. Taken together, these finding substantiate the potential anticancer activity of Gd2O3@BSA-CUR nanoparticles against nasal squamous cell carcinoma, but the results obtained demand further studies to assess their full potential.

Harnessing the power of Neobacillus niacini AUMC-B524 for silver oxide nanoparticle synthesis: optimization, characterization, and bioactivity exploration.

BACKGROUND: Biotechnology provides a cost-effective way to produce nanomaterials such as silver oxide nanoparticles (Ag2ONPs), which have emerged as versatile entities with diverse applications. This study investigated the ability of endophytic bacteria to biosynthesize Ag2ONPs. RESULTS: A novel endophytic bacterial strain, Neobacillus niacini AUMC-B524, was isolated from Lycium shawii Roem. & Schult leaves and used to synthesize Ag2ONPS extracellularly. Plackett-Burman design and response surface approach was carried out to optimize the biosynthesis of Ag2ONPs (Bio-Ag2ONPs). Comprehensive characterization techniques, including UV-vis spectral analysis, Fourier transform infrared spectroscopy, transmission electron microscopy, X-ray diffraction, dynamic light scattering analysis, Raman microscopy, and energy dispersive X-ray analysis, confirmed the precise composition of the Ag2ONPS. Bio-Ag2ONPs were effective against multidrug-resistant wound pathogens, with minimum inhibitory concentrations (1-25 µg mL-1). Notably, Bio-Ag2ONPs demonstrated no cytotoxic effects on human skin fibroblasts (HSF) in vitro, while effectively suppressing the proliferation of human epidermoid skin carcinoma (A-431) cells, inducing apoptosis and modulating the key apoptotic genes including Bcl-2 associated X protein (Bax), B-cell lymphoma 2 (Bcl-2), Caspase-3 (Cas-3), and guardian of the genome (P53). CONCLUSIONS: These findings highlight the therapeutic potential of Bio-Ag2ONPs synthesized by endophytic N. niacini AUMC-B524, underscoring their antibacterial efficacy, anticancer activity, and biocompatibility, paving the way for novel therapeutic strategies.

Effectiveness of white tea-mediated silver nanoparticles as an intracanal irrigant against Enterococcus faecalis: An in vitro study.

BACKGROUND: The probability of a positive outcome of root canal therapy is substantially higher if the infection is eradicated successfully before the obturation of the root canal system. Irrigation is an essential aspect of root canal debridement, as it enables more thorough cleaning than is possible with root canal instrumentation alone. To overcome the side effects of chemical irrigants, there has been a search for herbal medicines as substitutes. OBJECTIVES: The aim of the present study was to explore the antimicrobial efficacy of white tea-mediated silver nanoparticles (AgNPs) formulated as an intracanal irrigant against Enterococcus faecalis, and to compare it with the efficacy of chlorhexidine and sodium hypochlorite irrigants. MATERIAL AND METHODS: The experimental groups were as follows: group I - white tea-mediated AgNPs; group II - 2% chlorhexidine; and group III - 2.5% sodium hypochlorite. The characterization of AgNPs was performed using ultraviolet-visible (UV-Vis) spectroscopy and transmission electron microscopy (TEM) analysis. Enterococcus faecalis was inoculated onto Mueller-Hinton agar plates. The disks impregnated with irrigants were placed on the inoculated plates and incubated aerobically at 37°C for 24 h. Then, the growth inhibition zones were measured. Statistical analysis was performed using the one-way analysis of variance (ANOVA) and the post hoc tests. RESULTS: A concentration of 50 µL of white tea-mediated AgNPs exhibited the greatest zone of inhibition (32 ±2 mm), followed by 2% chlorhexidine (25 ±1 mm) and 2.5% sodium hypochlorite (23 ±3 mm). CONCLUSIONS: White tea-mediated AgNPs showed promising results in the elimination of E. faecalis, being superior to chlorhexidine and sodium hypochlorite irrigants.