Reductionist Research Articles

Foliar-applied silicate potassium modulates growth, phytochemical, and physiological traits in Cichorium intybus L. under salinity stress

One of the major problems endangering plant growth and productivity worldwide is salt stress. This study aimed to assess the effects of potassium silicate (K2O3Si) on the physical, biochemical, and morphological characteristics of chicory (Cichorium intybus L.) under various levels of salinity stress. The plants were treated with K2O3Si at concentrations of 0, 1, 2, and 3 mM and cultivated under different salt stress conditions (0, 80, 160, and 240 mM NaCl). The findings revealed that salt stress led to decreased root and shoot dry weights, Fv/Fm ratio, chlorophyll a, b, and total chlorophyll, as well as inulin contents. However, foliar exposure to K2O3Si at all salinity levels resulted in improvements in the measured traits. As salinity levels increased, there was a corresponding increase in the accumulation of sodium ions (Na+) and a sharp reduction in potassium ions (K +) in the shoot. Nonetheless, treatment with K2O3Si caused a decrease in Na + accumulation and an improvement in K+ content under all salinity levels. Carotenoid content increased under 80 mM salinity stress, but decreased with higher salinity levels. Application of K2O3Si at all levels resulted in increased carotenoid content under salinity stress conditions. The content of MDA increased significantly with increasing salinity stress, particularly at 240 mM. However, foliar spraying with K2O3Si significantly decreased MDA content at all salinity levels. Salinity stress up to 160 mM increased the total phenol, flavonoid, and anthocyanin contents, while 240 mM NaCl decreased the biosynthesis of phytochemicals. Additionally, the use of K2O3Si increased the content of total phenol, flavonoid, and anthocyanin at all salt levels. Foliar application of K2O3Si increased the tolerance of chicory plants to salinity stress by reducing MDA and increasing phenolic compounds and potassium content. These results suggest that exogenous K2O3Si can be a practical strategy to improve the growth and yield of chicory plants exposed to saline environments.

Synthesis of cobalt nanoparticles in aqueous solutions assisted by polymer/inorganic hybrid

Hydrophilic polymer/inorganic hybrids (PIH) containing silica nanoparticles and polyacrylamide chains proved to be effective matrices for the in situ synthesis of cobalt nanoparticles. PIH sample was synthesized by free-radical polymerization of acrylamide from the unmodified surface of SiO2 nanoparticles and characterized by elemental analysis, dynamic thermogravimetric analysis, static light scattering, potentiometric titration, viscometry and transmission electron microscopy (TEM). The processes of borohydride reduction of cobalt ions from the Co(NO3)2·6H2O solution to nanoparticles in water medium and aqueous solutions of PIH were studied as a function of the concentrations of metal salt and hybrid concentrations using UV-Vis spectroscopy and TEM. A special approach to characterize the kinetics and efficiency of CoNPs formation in water medium and hybrid solutions using UV-Vis spectroscopy was implemented. The kinetic parameters of the CoNPs formation process as well as the yield, size, and morphology of nanoparticles in hybrid solutions and water medium at various concentrations of metal salt and hybrid were determined. The growth of both concentrations of reagents had a positive effect on the rate of formation of metal nanoparticles and their yield, but in all cases, the reduction process developed much slower in hybrid solutions compared to pure water. The morphology of the CoNPs/PIH nanocomposites was mainly represented by separate swollen hybrid particles containing metal nanoparticles with dav~3 nm.

Active Dendrite Suppression by Ferroelectric Membrane Separators in Rechargeable Batteries.

Anodic dendrite formation is a critical issue in rechargeable batteries and often leads to poor cycling stability and quick capacity loss. Prevailing strategies for dendrite suppression aim at slowing down the growth rate kinetically but still leaving possibilities for dendrite evolution over time. Herein, we report a complete dendrite elimination strategy using a mesoporous ferroelectric polymer membrane as the battery separator. The dendrite suppression is realized by spontaneously reversing the surface energetics for metal ion reduction at the protrusion front, where a positive piezoelectric polarization is generated and superimposed as the protrusion compresses the separator. This effect is demonstrated first in a Zn electroplating process, and further in Zn-Zn symmetric cells and Zn-NaV3O8·1.5H2O full cells, where the dendritic Zn anode surfaces are completely turned into featureless flat surfaces. Consequently, a substantially longer charging/discharging cycle is achieved. This study provides a promising pathway toward high-performance dendrite-free rechargeable batteries.

Ultrafine Ni-MoOx Nanoparticles Anchored on Nitrogen-Doped Carbon Nanosheets: A Highly Efficient Noble-Metal-Free Catalyst for Ammonia Borane Hydrolysis.

The development of low-cost and high-efficiency catalysts for the hydrolytic dehydrogenation of ammonia borane (AB, NH3BH3) is still a challenging technology. Herein, ultrafine MoOx-doped Ni nanoparticles (~3.0 nm) were anchored on g-C3N4@glucose-derived nitrogen-doped carbon nanosheets via a phosphate-mediated method. The strong adsorption of phosphate-mediated nitrogen-doped carbon nanosheets (PNCS) for metal ions is a key factor for the preparation of ultrasmall Ni nanoparticles (NPs). Notably, the alkaline environment formed by the reduction of metal ions removes the phosphate from the PNCS surface to generate P-free (P)NCS so that the phosphate does not participate in the subsequent catalytic reaction. The synthesized Ni-MoOx/(P)NCS catalysts exhibited outstanding catalytic properties for the hydrolysis of AB, with a high turnover frequency (TOF) value of up to 85.7 min-1, comparable to the most efficient noble-metal-free catalysts and commercial Pt/C catalyst ever reported for catalytic hydrogen production from AB hydrolysis. The superior performance of Ni-MoOx/(P)NCS can be ascribed to its well-dispersed ultrafine metal NPs, abundant surface basic sites, and electron-rich nickel species induced by strong electronic interactions between Ni-MoOx and (P)NCS. The strategy of combining multiple modification measures adopted in this study provides new insights into the development of economical and high-efficiency noble-metal-free catalysts for energy catalysis applications.

Evaluating the efficiency of silver nanoparticles prepared using <i>Pseudomonas fluorescens</i> and <i>Bacillus thuringiensis</i> subsp. <i>tenebrionis</i> in controlling eggs and adults of <i>Callosobruchus maculatus</i> (F.) (Coleoptera: Bruchidae)

This study aimed to evaluate the efficiency of silver nanoparticles (AgNPs) which are prepared biologically by two bacterial species, Bacillus thuringiensis tenebrionis (Btt) and Pseudomonas fluorescens (P.f) to control southern cowpea beetle insect, Callosobruchus maculatus. Many features of the prepared nanoparticles were examined, and the results obtained showed that the highest absorption value of AgNPs was at 262 nm. Whereas the results of FTIR analysis showed that several compounds played a role in the silver ions reduction process, which included alcohol, alkane, primary amine, and amine group. The scanning electronic microscopic images showed that the average diameter of nanoparticles which was created by P.f was 48.52 nm, while it was 56.08 nm for the nanoparticles prepared by Btt. The study showed no significant differences between the activity of both AgNP types against C. maculatus eggs, while a significant preference was recorded for the activity of Btt AgNPs against the C. maculatus adults. The highest percentage of unhitched eggs was 53.8% recorded at 3000 ppm concentration, while Btt AgNPs gave 59.6% at 3000 ppm. The highest mortality rate of the adults who were treated by Btt AgNPs was 58.8 % at 3000 ppm concentration, while it was recorded 50% at 3000 ppm with P.f AgNPs treatment. The current study demonstrates the efficiency of biologically prepared AgNPs in controlling C. maculatus insect life stages, which encourages using of these nanoparticles as a modern strategy in management of insect pests.

Regulating concentration of surface oxygen vacancies in Bi2MoO6/Bi-MOF for boosting photocatalytic ammonia synthesis

Surface oxygen vacancies (OVs) engineering has been widely adopted as an effective strategy to enhance photocatalytic performance. At present, photocatalytic systems capable of precisely regulating surface OVs concentrations, which could help illuminate the effects of the surface OVs concentration on N2 fixation activity, are still scarce. Herein, bismuth-based metal organic framework (Bi-MOF) was loaded onto the surface of Bi2MoO6 (BMO) as an operable platform, and the OVs concentration in the Bi-MOF component of BMO/Bi-MOF could be regulated by reduction of bismuth ions therein. Experimental results confirm that optimum construction of OVs in the Bi-MOF promotes the photoelectrons transfer from BMO to Bi-MOF, facilitating the activation of N2 at OVs. Consequently, the optimized catalyst shows superior performance in NH3 production, which reaches 125.78 μmol h−1 g−1, 21.4 higher than that of BMO. This work underline the significance of regulating surface OVs concentration, providing inspiration for the development of efficient OVs-modified photocatalysts.

Yarrowia lipolytica CMGB32 Biosurfactants Produced Using n-Hexadecane: Developing Strategies for Environmental Remediation

The yeast Yarrowia lipolytica degrades petroleum compounds, including alkanes, via the monoterminal oxidation pathway, the hydrophobic carbon substrate assimilation is mediated by biosurfactants, and extracellular amphiphilic molecules are produced by the yeast cell. This study focuses on the ability of the strain Y. lipolytica CMGB32 to degrade n-hexadecane by producing biosurfactants with high potential for bioremediation. The hydrocarbon-degrading potential of the yeast strain was observed via a 2,6-dichlorophenolindophenol (DCPIP) test in Bushnell–Hass medium with 1% n-hexadecane, and cell hydrophobicity was expressed as microbial adhesion to hydrocarbons (MATH). Biosurfactant production on yeast peptone (YP) with 1% n-hexadecane was estimated after 72 h using the emulsification index (E24%) against toluene. Crude biosurfactant (cell-free broth) stability tests were performed at different temperatures (4 °C, 70 °C) and NaCl concentrations (2–10%). The effects of a biosurfactant on synthetic wastewater remediation comprised the growth curves (OD measurements) of natural heavy metal degrader Rhodotorula mucilaginosa, determination of nutrients (spectrophotometrically), physico-chemical parameters, and removal capacity of lead and cadmium ions (via inductively coupled plasma mass spectrometry—ICP-MS). The antimicrobial and anti-adherence activities of 20 mg/mL and 40 mg/mL of the biosurfactant against pathogenic Candida krusei strains involved growth observations and the crystal violet microtiter method. The DCPIP decolorization occurred after six days, corresponding to the maximum growth phase of the Y. lipolytica culture. After 72 h, the cells presented high hydrophobicity (82.61% MATH) and stable biosurfactant production (E24% 47%). The crude biosurfactant (5%) increased the growth of R. mucilaginosa strains cultivated on synthetic wastewater cultures contaminated with Pb2+ and Cd2+, increased the conductivity and COD (86%) of the samples, and determined Pb2+ (66%) and Cd2+ (42%) ions reduction. The concentrated biosurfactant inhibited C. krusei growth (70%) and biofilm adherence. In conclusion, Y. lipolytica CMGB32 shows important potential for development of biosurfactant-based technologies for the remediation of heavy-metal- and emerging pathogen-contaminated wastewaters.

Suppressing the background of LC-ESI-MS analysis of permethylated glycans using the active background ion reduction device.

Mass spectrometry (MS) has revolutionized analytical chemistry, enabling precise identification and quantification of chemical species, which is pivotal for biomarker discovery and understanding complex biological systems. Despite its versatility, the presence of background ions in MS analysis hinders the sensitive detection of low-abundance analytes. Therefore, studies aimed at lowering background ion levels have become increasingly important. Here, we utilized the commercially available Active Background Ion Reduction Device (ABIRD) to suppress background ions and assess its effect on the liquid chromatography-electrospray ionization (LC-ESI)-MS analyses of N-glycans on the Q Exactive HF mass spectrometer. We also investigated the effect of different solvent vapors in the ESI source on N-glycan analysis by MS. ABIRD generally had no effect on high-mannose and neutral structures but reduced the intensity of some structures that contained sialic acid, fucose, or both when methanol vapor filled the ESI source. Based on our findings on the highest number of identified N-glycans from human serum, methanol vapor in the ion source compartment may enhance N-glycan LC-ESI-MS analyses by improving the desolvation of droplets formed during the ESI process due to its high volatility. This protocol may be further validated and extended to advanced bottom-up proteomic/glycoproteomic studies for the analysis of peptide/glycopeptide ions by MS.

ТЕРМОДИНАМИЧЕСКИЙ АНАЛИЗ ОКИСЛИТЕЛЬНО – ВОССТАНОВИТЕЛЬНЫХ РЕАКЦИЙ, ПРОТЕКАЮЩИХ ПРИ ГАЛЬВАНОКОАГУЛЯЦИОННОЙ ОЧИСТКЕ СТОКОВ

Abstract. One of the most important environmental problems is the purification of industrial wastewater from heavy metal ions. Various methods are used to solve this problem: chemical, physico-chemical, sorption, but the most promising method for cleaning industrial wastewater containing heavy metal ions, namely copper, nickel and zinc, is the galvanocoagulation method. However, the literature does not sufficiently cover the processes of cementation of heavy metals on cathode loading. A physico-chemical approach to this process is necessary to confirm the process of separation of heavy metal ions from wastewater in the form of sediment and the creation of new industrial wastewater treatment schemes. The composition of the loading is essential in galvanocoagulation neutralization, therefore, in order to determine the effect of the type of active loading, a carbon mineral sorbent (SGN) obtained from ores of cryptocrystalline graphite (Noginsky deposit of the Krasnoyarsk Territory) was used. The studies were carried out in a galvanocoagulation module by passing wastewater through a loading consisting of a mixture of iron shavings and granules of carbon mineral sorbent based on ores of cryptocrystalline graphite (SGN). At the same time, the air dispersed in the lower part of the device was bubbled through the loading. As a result of the operation of the Fe-SGN short-circuited galvanic cell, iron scrap was dissolved and its intensive oxidation to Fe3+ by air oxygen. The article considers the mechanism of galvanocoagulation neutralization of wastewater based on thermodynamic analysis of redox reactions occurring during galvanocoagulation wastewater treatment.
 Subject of the study: both model and real wastewater from the production of electroplating coatings containing copper, zinc and nickel ions with the following concentrations were used: =60 mg/dm3; =15 mg/dm3; =20 mg/dm3
 Materials and methods: galvanocoagulation neutralization using a short-circuited Fe-SGN galvanic cell (carbon mineral sorbent)
 Results: the physico-chemical patterns of the galvanocoagulation process of wastewater treatment have been studied and the thermodynamic parameters of heavy metal ion reduction reactions have been determined
 Conclusions. It has been experimentally established that it is possible to intensify the process of galvanocoagulation of wastewater containing heavy metal ions by using a carbon mineral sorbent as a cathode loading, which reduces the processing time with a high purification effect and a difficult-to-dissolve precipitate is formed.

Solanum trilobatum leaf extract-derived silver nanoparticles downregulate the PI3K/AKT/mTOR signaling pathway and attenuate oral squamous cell carcinoma cell proliferation

Introduction: Oral cancer’s aggressive nature poses a significant health risk, demanding timely diagnosis and effective treatment. Despite progress in conventional therapies like chemotherapy and surgery, their limitations drive the exploration of alternative strategies. This study assessed Solanum trilobatum-derived silver nanoparticles (AgNPs) in impacting cancer cell cycles, inducing apoptosis, and modulating key pathways, including the phosphoinositide 3-kinase (PI3K)/Protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway, leveraging phytotherapy and nanotechnology—a promising frontier in cancer treatment. Methods: AgNPs were synthesized through the reduction of ions and stabilized using aqueous leaf extracts of S. trilobatum. After the characterization of AgNPs, the mRNA Gene Expression and mitochondrial membrane potentials (MMPs) were assessed. DNA fragmentation was done and DNA pattern by gel documentation system was observed. The study also assessed the modulation of the PI3K/Akt/mTOR cascade, impacting tumor growth and proliferation. Results: Biosynthesized AgNPs were characterized using UV-visible spectrophotometry (UVvis), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy. DNA fragmentation exhibited a typical ladder pattern. Dose-dependent changes in MMP were observed in the treated oral cancer cells. The effect of S. trilobatum-derived AgNPs in targeting the cell signaling pathway correlated significantly with their anticancer potency (P<0.001). Conclusion: This study reveals S. trilobatum leaf extract-based AgNPs as a natural cytostatic agent against oral squamous carcinoma. Utilizing nature’s resources and nanoscale science, they hold promise for enhancing oral cancer treatment outcomes and survival rates.

A sustainable approach to prepare green synthesis of copper nanoparticles of Bauhinia variegata & Saussurea lappa: Unveiling in-vitro anti-obesity applications

Nanoparticles have different shapes and sizes between the range of 1–100 nm, which show advantages for stabilizing compounds, higher carrier capacity, and lower costs. Metal nanoparticles such as copper, gold, silver, and zinc are favorable components for various applications due to their interesting properties. In the present study, nanoparticles were synthesized by reduction with flower extracts of Bauhinia variegate &Saussurea lappa that were used to stabilize the copper nanoparticles. Furthermore, the characterization of plants synthesized copper nanoparticles was carried out through UV–visible dynamic light scattering. Additionally, morphological characterization of nanoparticles was confirmed by scanning electron microscopy and energy dispersive X-ray spectroscopy confirmed the elemental composition of copper nanoparticles. Powder X-ray diffraction was conducted for the analysis of crystallinity, purity, and crystal size of plant-synthesized copper nanoparticles. The average particle size was evaluated and exhibited the particle size at the peak of 8.721 nm and 98.03 nm for flower extracts of Bauhinia variegate &Saussurea lappa copper nanoparticles. The Fourier Transform Infrared spectrum was taken to scrutinize the various functional groups that were responsible for the reduction of the copper ions. The antimicrobial results against the bacterial strains with the positive test results of the zone of inhibition were for Bauhinia variegate (17 mm, 18 mm, 19 mm, and 18 mm) and Saussurea lappa (17 mm, 19 mm, 18 mm, and 18 mm) respectively for plants synthesized copper nanoparticles against the Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa. Lipase inhibition assay and Amylase inhibition assay with different concentrations (20 μg/mL to 100 μg/mL) for Bauhinia variegate &Saussurea lappa (12.34 %–59.67 % and 10.50 %–47.01 %) and (34.52 %–89.02 % and 22.34 %–56.45 %) confirmed the anti-obesity and anti-diabetic activities of plants extract synthesized copper nanoparticles.

Syzygium cumini-mediated synthesis of rGO/Ag-Au nanostructures: Efficient catalysts for rapid degradation of organic dyes

BackgroundThe increasing human health risk caused by contamination of water by both natural and synthetic dye pollutants has become a crucial issue and poses an immense urge to find a sustainable approach for the removal of dye contaminants from wastewater. Photocatalysis performed in the presence of nanomaterials holds huge promise as an efficient and environmentally safe oxidation technology for organic dye removal from waste water. MethodsOur preparation methodology utilizes the extract derived from the endocarp of Syzygium cumini (SC) effects for concurrent reduction of GO and metal ions to form rGO/Ag-Au. The prepared rGO/Ag-Au nanostructures effectively breakdown organic dye pollutants like methylene blue (MB) and methyl orange (MO) dyes. Significant findingsA robust interaction between the rGO matrix and the Ag-Au nanoparticles was established by structural characterization, while morphological investigation displayed the nanoscale Ag-Au particles uniformly coated over the rGO sheet surface. The catalytic efficiency of the rGO/Ag-Au nanocomposite toward methylene blue (MB) and methyl orange (MO) chromophores decomposition was assessed with the aid of sodium borohydride (NaBH4). The decoration of well-spaced Ag-Au nanoparticles over the rGO sheet created firm catalytic active sites in the rGO/Ag-Au composite. With the improved catalytic active surface, the MB/MO dye was completely removed in a very short time of 2.5 to 5 min. The rGO/Ag-Au composite exhibited exceptional catalytic prowess in the disintegration of both dyes, leading to complete degradation. The remarkable efficacy in the dye degradation process can be attributed to the predominance of both electrostatic as well as π-π interactions between the nanocomposite and the dyes. As a result, the current study has developed an easy-to-use and green method for creating rGO/Ag-Au composites, offering a workable way to dispose of hazardous organic dyes in an affordable and efficient way.

Green synthesis of gold nanoparticles using macroalgae Halimeda macroloba extract and their photocatalytic degradation of methylene blue and methyl orange

AbstractGreen synthesis of gold nanoparticles (AuNPs) is gaining attention of researchers because of their varieties of biomedical and environmental applications. This study reported the novel eco‐friendly synthesis of AuNPs using green macroalgae Halimeda macroloba (HM) extract and evaluate their photocatalytic potential. The green synthesized H. macroloba mediated gold nanoparticles (HM‐AuNPs) was characterized using UV–visible spectrophotometry, Fourier‐transform infrared (FT‐IR) spectroscopy, transmission electron microscope (TEM), scanning electron microscope‐energy dispersive spectroscopy, x‐ray photoelectron spectroscopy (XPS), and particle size distribution (PSD) anlaysis. The UV–visible spectrum shows a sharp intense plasmonic resonance peak at 543 nm. The bioactive compounds present in HM were primarily responsible for the biological reduction of gold ions validated by FT‐IR analysis. XRD analysis proved the crystalline face centered cubic structure of the HM‐AuNPs. The average particle size of 18.72 nm and morphological evidences were obtained from the images from TEM. The metallic form of biosynthesised HM‐AuNPs was confirmed by XPS results with a distinctive binding energy. The photocatalytic degradation ability of the green synthesized HM‐AuNPs was investigated against the methylene blue (MB) and methylene orange (MO) dyes under sunlight irradiation. The HM‐AuNPs exhibited 97.23% and 89.91% photocatalytic activity against MB and MO after 90 min of exposure to sunlight, respectively. The overall results of this research indicate that H. macroloba mediated HM‐AuNPs can be used as an effective option for the degradation of industrial dyes.

Mediated Electrosynthesis of Nanocomposites of Gold Nanoparticles with Cyclobis (paraquat-p-phenylene)

The result of cyclobis(paraquat-p-phenylene) (CBPQT4+) –mediated reduction of gold ions generated by anodic oxidation of metallic gold in MeCN (50% vol.)—H2O/0.05 M Bu4NCl medium in the absence and presence of such stabilizers as cetyltrimethylammonium chloride and polyvinylpyrrolidone is polydisperse aggregated composite nanoparticles with sizes ranging from several nm to 100 nm or more. The resulting AuNP@(CBPQT4+)n nanocomposite is a gold nanoparticle encapsulated in a shell of macrocycle molecules. CBPQT4+ is bound to the surface of the gold nanoparticle by donor-acceptor interactions between the electron-withdrawing viologen units and the electron-donating metal particle. Theoretical calculations suggest that the cavity of the bound macrocycle is not empty, but filled with 10–12 gold atoms. CBPQT4+ presumably forms a monomolecular layer on the metal surface, and its excess amount is involved in the aggregation and sedimentation of the nanocomposites. The encapsulation of AuNPs in the macrocyclic shell is the main reason for the suppression of the metal catalytic activity in the test reaction of p-nitrophenol reduction with sodium borohydride.

An evaluation of the pharmacological responses of metal nanoparticles derived from aqueous extract of Caralluma adscendens R. Brown var. Bicolor

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 IC50 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.

Spatiotemporal tracking of intracellular nanoparticles using complementary imaging systems reveals acute ferroptosis triggered by burst reduction of ferric ions

Uptake and intracellular trafficking of nanoparticles are tightly regulated by their interactions with cellular organelles and physiological microenvironment. Although the dynamic physicochemical reactions at the interface of nanoparticles and cells ultimately determine the intracellular distribution and fate, microscopic tracing and quantitative analysis of the nanoparticles have been hampered by the limited resolution associated with individual nanoparticle trafficking. Herein, we report spatiotemporal investigations on autophagic clearance of biodegradable iron oxide-silica core-shell nanoparticles in terms of intracellular trafficking and ionic dissolution at a single cell level using multimodal imaging systems. By combining transmission electron microscopy and super-resolution confocal laser scanning microscopy with fluorescence correlation spectroscopy, the complementary imaging analysis exclusively shows the intracellular uptake, endosomal fusion and biodegradative clearance, leading to identify the step-by-step endocytic transport pathway and autophagic degradation pathways. Tracing the intracellular trafficking of nanoparticles reveals that they are spontaneously transported from endosomes to lysosomes, and transiently stimulate autophagy while maintaining cell viability. While protecting iron oxide core, the silica shell is gradually degraded during endocytosis and autophagic clearance, resulting in ionic dissolution of iron oxide in acidic environment. Moreover, burst reduction of ferric ions by adding ascorbic acid readily triggers acute ferroptosis owing to rapid supplement of ferrous ions and Fenton reaction in cancer cells. The complementary imaging strategy provides insights into the design of biocompatible nanomedicines for cellular delivery and the degradative mechanisms beyond the intracellular fate.

Covalent organic frameworks surface-anchored with silver nanoparticles for colorimetric detection of dopamine based on its oxidase-mimicking activity

Sensitive detection of dopamine (DA) is essential for the diagnosis of nervous system diseases. Herein, a nanozyme-based colorimetric platform for DA determination was proposed. Using an imine-type covalent organic framework (COF-TD) as a host matrix, a nanozyme (AgNPs@COF-TD) was fabricated by anchoring silver nanoparticles (AgNPs) on the surface of COF-TD via in situ reduction of silver ions. Various characterization results confirmed the successful synthesis of flower-like AgNPs@COF-TD with surface-anchored AgNPs, which could expose more active sites. The as-prepared AgNPs@COF-TD exhibited satisfactory oxidase-mimicking activity with a low Km, which could catalyze the oxidation of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to blue oxidized TMB (oxTMB) with significant absorbance at 657 nm. The introduction of DA not only reduced blue oxTMB to colorless TMB but also competed with TMB for the active sites of AgNPs@COF-TD, making a significant decrease in absorbance. Therefore, a label-free sensing strategy based on the oxidase-mimicking activity of AgNPs@COF-TD was successfully established for the colorimetric detection of DA, with a detection limit down to 0.2 μM. The practical applicability of this assay was further validated by analyzing DA-spiked human urine samples. This work provided a facile approach to prepare COF-based nanozymes, and demonstrated their great potential in colorimetric detection and bioanalysis.

Construction of bionic sea urchin-like ZnFe2O4/Bi2S3 heterojunction for microwave-induced catalytic reduction of Cr(VI): Performance and mechanism insights

The construction of microwave-responsive catalysts with high reactivity for detoxifying heavy metal ions, particularl Cr(VI) in wastewater, poses a significant challenge. In this study, a novel microwave-responsive sea urchin-like ZnFe2O4/Bi2S3 heterojunction catalyst was designed for the rapid reduction of Cr(VI) from wastewater. Thanks to the unique “tip” structure of its surface, and its exceptional microwave absorption capabilities, the as-prepared sea urchin-like ZnFe2O4/Bi2S3 heterojunction was capable of removing 98 % pollutant from a 50 mg/L Cr(VI) solution under microwave irradiation for 40 min, even in a near-neutral aqueous environment. Importantly, this sea urchin-like ZnFe2O4/Bi2S3 heterojunction maintains efficient microwave-induced catalytic removal of Cr(VI) in complex water environments containing coexisting pollutants such as Methylene Blue (MB), Methyl Orange (MO), Crystal Violet (CV), Rhodamine B (RhB), Tetracycline (TC), Reactive Red X (RBR-X-3B), Congo Red (CR), Ketoprofen (KTP) drug, Norfloxacin (NOF) and Uranium(VI) (U(VI)). Furthermore, density functional theory (DFT) calculations reveal that the inhibited interface between ZnFe2O4 and Bi2S3 accelerates the transfer of electrons from ZnFe2O4 to Cr(VI) adsorbed on the surface of Bi2S3. Additionally, the synergistic interaction of ZnFe2O4 with Bi2S3 promotes the conversion of *Cr2O72- ions to *CrO3H3 ions and reduces the energy barrier of the rate determining hydrogenation step from −0.60 to −1.70 eV. This work serves as a reference for designing highly active microwave-responsive heterojunction catalysts, and offers theoretical guidance for a deeper understanding behind the mechanism of microwave-induced catalytic reduction of heavy metal ions.

Synthesis of Gold Clusters and Nanoparticles Using Cinnamon Extract-A Mechanism and Kinetics Study.

In this work, UV-Vis spectrophotometry, High Resolution Scanning Transmission Electron Microscopes and selected experimental conditions were used to screen the colloidal system. The obtained results complement the established knowledge regarding the mechanism of nanoparticle formation. The process of gold nanoparticles formation involves a two-step reduction of Au ions to Au(0); atom association and metastable cluster formation; autocatalytic cluster growth; ultra-small particle formation (1-2 nm, in diameter); particle growth and larger particles formation; and further autocatalytic crystal growth (D > 100 nm). As a reductant of Au(III) ions, a cinnamon extract was used. It was confirmed that eugenol as one of the cinnamon extract compounds is responsible for fast Au(III) ion reduction, whereas cinnamaldehyde acts as a gold-particle stabilizer. Spectrophotometry studies were carried out to track kinetic traces of gold nanoparticle (D > 2 nm) formation in the colloidal solution. Using the Watzky-Finke model, the rate constants of nucleation and autocatalytic growth were determined. Moreover, the values of energy, enthalpy and entropy of activation for stages related to the process of nanoparticle formation (Index 1 relates to nucleation, and Index 2 relates to the growth) were determined and found to be E1 = 70.6 kJ, E2 = 19.6 kJ, ΔH1 = 67.9 kJ/mol, ΔH2 = 17 kJ/mol, ΔS1 = -76.2 J/(K·mol), ΔS2 = -204.2 J/(K·mol), respectively. In this work the limitation of each technique (spectrophotometry vs. HRSTEM) as a complex tool to understand the dynamic of the colloidal system was discussed.

Extended study of the influence of europium doping on phosphate glass

The phosphate glasses with various Eu2O3 concentrations (0.1–3.0 w/w%) were synthesized and studied regarding the influence of europium dopant on the properties of irradiated phosphate glasses. During studies, samples were irradiated using two types of ionizing radiation sources (β− and γ), with obtained doses up to 40 kGy. TL studies were investigated using various methods, such as TL response vs. radiation dose and the TMax-Tstop method. To further investigate, if increasing the europium concentration affects the structure of electron traps, Computer Glow Curve Deconvolution studies linked with various heating rates methods were applied –increasing the concentration of dopant does not influence the number and energy of electron traps in irradiated samples. This fact was also supported by the results of the thermoluminescence spectrum – where no additional signals, besides wide signals from native glass were observed. OSL and IRSL studies were also conducted, for OSL we observed quenching of the signals, similar as in the TLD case. For IRSL studies all samples didn't display any signals. Finally, to understand if Eu3+ also has a “protective” effect, decreasing the yield of generating F-centers during irradiation, UV-VIS spectroscopy was used. It was established that samples doped with europium oxide possess ca. 20% lower signals at F-center maximum (at 475 nm), the building-up maximum at 320 nm was observed, characteristic of the absorption band of Eu2+. All data indicate that europium in phosphate glass is taking the role of an efficient electron quencher. This quenching phenomenon occurs in three ways: first (direct) when the ion reduction process (Eu3+→Eu2+) competes with the formation of F-centers, and second (indirect) when during heating electrons coming from F-centers were quenched by near Eu3+ ions. The third mechanism of quenching occurs through the electron's non-radiative transition induced by increased stress in the glass matrix caused by a large ionic radius of the dopant.