Selenious Acid Research Articles

Selenic Acid Etching Assisted Atomic Engineering for Designing Metal-Semimetal Dual Single-Atom Catalysts for Enhanced CO2 Electroreduction.

Single-atom catalysts are promising for electrocatalytic CO2 conversion but face challenges in controllable syntheses. Herein, a facile selenic acid etching-assisted strategy has been developed to fabricate a hybrid metal-semimetal dual single-atom catalyst for electrocatalytic CO2 reduction. This strategy enables the simultaneous generation of monodisperse active sites and hierarchical morphologies with hollow nanostructures. The as-obtained catalyst with Fe-Se dual single-atom sites supported by porous nitrogen-doped carbon (FeSe-NC) shows exceptional catalytic activity and CO selectivity, delivering a Faradaic efficiency (FE) of >97% with industrially comparable jCO, superior to the Fe single-atom catalyst. Moreover, the FeSe-NC-based rechargeable Zn-CO2 battery delivers a high power density (2.01 mW cm-2) and outstanding FECO (>90%), as well as excellent cycling stability. Experimental results together with theoretical calculations reveal that the etching-induced defects and the Se-modulated Fe centers with asymmetrical polarized charge distributions synergistically facilitate the key intermediate *CO desorption and thus accelerate the CO2-to-CO conversion.

Solid-state synthesis of nickel selenide for high-performance supercapacitors

This study focuses on the synthesis and electrochemical characterization of nickel diselenide (NiSe2) as a promising electrode material for supercapacitors. NiSe2 was synthesized through a facile solid-state process involving the mixing of nickel acetylacetonate and selenous acid, followed by drying and sintering at 500 °C under inert conditions. The resulting NiSe2 exhibited a granular structure with worm-like surface architecture and particle size ranging from 20 to 100 nm. The electrochemical performance of NiSe2 was evaluated using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) in a 6 M KOH electrolyte. NiSe2 demonstrated a high specific capacitance of 744.7 F g−1 at a discharge rate of 1 A g−1, with an outstanding rate capability retaining the capacitance of 483.6 F g−1 at 10 A g−1, and exceptional long-term cycling stability. The kinetic analysis revealed that the energy storage mechanism in NiSe2 primarily involves diffusion-controlled charge storage. EIS further confirmed the favorable charge transfer properties of the NiSe2 electrode. Overall, NiSe2 synthesized via the proposed method shows great promise for application in high-performance supercapacitors.

Pristine Photopolymerizable Gelatin Hydrogels: A Low-Cost and Easily Modifiable Platform for Biomedical Applications.

The study addresses the challenge of temperature sensitivity in pristine gelatin hydrogels, widely used in biomedical applications due to their biocompatibility, low cost, and cell adhesion properties. Traditional gelatin hydrogels dissolve at physiological temperatures, limiting their utility. Here, we introduce a novel method for creating stable hydrogels at 37 °C using pristine gelatin through photopolymerization without requiring chemical modifications. This approach enhances consistency and simplifies production and functionalization of the gelatin with bioactive molecules. The stabilization mechanism involves the partial retention of the triple-helix structure of gelatin below 25 °C, which provides specific crosslinking sites. Upon activation by visible light, ruthenium (Ru) acts as a photosensitizer that generates sulphate radicals from sodium persulphate (SPS), inducing covalent bonding between tyrosine residues and "locking" the triple-helix conformation. The primary focus of this work is the characterization of the mechanical properties, swelling ratio, and biocompatibility of the photopolymerized gelatin hydrogels. Notably, these hydrogels supported better cell viability and elongation in normal human dermal fibroblasts (NHDFs) compared to GelMA, and similar performance was observed for human pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). As a proof of concept for functionalization, gelatin was modified with selenous acid (GelSe), which demonstrated antioxidant and antimicrobial capacities, particularly against E. coli and S. aureus. These results suggest that pristine gelatin hydrogels, enhanced through this new photopolymerization method and functionalized with bioactive molecules, hold potential for advancing regenerative medicine and tissue engineering by providing robust, biocompatible scaffolds for cell culture and therapeutic applications.

Molecular docking analysis of mosquito ribosomal protein in selenium nanoparticle bio-synthesis: Implications for pest and pathogen mitigation

BackgroundInsects, rich in diverse proteins, are crucial in nanoparticle biofabrication. This study explores mosquito proteins' potential to reduce selenium ions and produce Selenium nanoparticles (SeNPs). MethodsMosquito larval protein composition was determined via liquid chromatography-mass spectrometry (LC-MS). Molecular docking validated cytoskeletal proteins' efficacy, notably 40S ribosomal protein S7 (binding energy: -6.23) and β-tubulin (binding energy: -5.94), in facilitating selenium ion conversion to SeNPs. SeNPs, mediated by these proteins, were characterized using Ultra Violet-visible spectroscopy, revealing a peak at 295 nm. FT-IR analysis identified biomolecules responsible for capping SeNPs and converting selenious acid to SeNPs. Significant findingsLC-MS detected β-tubulin (1 peptide, 76 amino acids, 8.2 kDa) and 40S ribosomal protein S7 (2 peptides, 192 amino acids, 22.1 kDa). The FT-IR analysis showed peaks at 3420.89 (OH stretch), 2928.35 (aromatic CH stretch), 2344.02 (CC alkynes stretches), etc. X-Ray Diffraction confirmed SeNPs' crystalline structure. Scanning electron microscopy and transmission electron microscopy revealed smooth-surfaced SeNPs in spherical and rod-shaped forms. SDS PAGE analysis post-SeNPs synthesis confirmed 40S ribosomal protein S7 and β-tubulin presence. SeNPs exhibited antibacterial, anti-biofilm, antioxidant, photocatalytic, and insecticidal activities. Median lethal concentrations were 17.674 μg/mL for Culex quinquefasciatus, 31.117 μg/mL for Aedes aegypti, and 81.95 μg/mLfor R. dominica at 48 h. SeNPs suppressed S. aureus biofilm by 33.06 ± 8.26 % and E. coli by 13.8 ± 3.63 %. Vero cells showed no harm at 250 µg/mL SeNPs. At 100 μg/mL, SeNPs exhibited 52.94 % free radical scavenging, compared to 74 % for ascorbic acid. Protein-mediated nanoparticle preparation is favoured for biomedical applications due to ease of synthesis, eco-friendliness, conjugation capability, simple preparation, and utilization of pests.

Purification of process solutions from mercury by sorption

At JSC «Uralelectromed», selenium-containing raw materials and industrial products are processed, resulting in solutions containing a mixture of mercury with concentrations as follows (g/dm3): 157–210 Se; 0.004–0.02 Hg; 0.15–0.20 Te; 2–3 As; 0.15–0.20 Sb; and 45–50 S. To produce branded selenium, the mercury concentration in the solution must be kept below 0.001 g/dm3. Various methods, such ashydrometallurgical and electrochemical processes, are known for mercury purification from solutions. JSC «Uralelectromed» has selected sorption technology for mercury removal using the weak-base macroporous anionite Lewatit MP-68 (Germany), which allows for control over the degree of solution purification. In pursuit of import substitution for the Western European sorbent Lewatit MP-68, we investigated several pre-selected industrial sorbents for extracting mercury anionic complexes produced in Russia (AM-2B, AN-31, AV 17-8, VP-3Ap), China (Seplite MA 940 and LSC 710), and India (Tulsion CH-95 and CH-97). Initially, in static mode, we determined the distribution coefficient (Cd), the degree of element extraction (ε), the static exchange capacity of the resins (SEC, g/dm3), and the mercury/selenium separation coefficient (DHg/Se) which led to the selection of the best samples: AV 17-8, Seplite MA 940, AM-2B, and CH-97, with SEC values of 0.95–0.97 g/dm3 (SEC = 0.98 g/dm3 of resin Lewatit MP-68). Subsequently, in dynamic mode, we ranked the ionites by decreasing dynamic exchange capacity (DEC / TDEC): AV 17-8 ≥ Lewatit MP-68 > AM-2B > Seplite MA 940 > Tulsion CH-97. Resins AV 17-8, Seplite MA 940, and AM-2B demonstrated similar dynamic sorption characteristics; under comparable conditions, mercury breakthrough occurred after processing at least 950 specific volumes of the initial solution. In contrast, with Lewatit MP-68 ionite, mercury breakthrough occurred after no more than 750 specific volumes, indicating the need to increase the number of sorption steps in the solution purification cascade. Considering the totality of ion-exchange properties, for further industrial testing, it is recommended to use the domestically produced resin AV 17-8 instead of the foreign sorbent Lewatit MP-68 in the sorption purification process of selenic acid to remove mercury, thereby ensuring the production of branded selenium.

Selenium enrichment and quality improvement of Origanum vulgare plants grown under in vitro condition with salicylic acid

One of the important sources of human selenium intake is vegetables, so increasing of selenium in edible parts of plants, biofortification, provides an effective approach to reduce selenium deficiency. Origanum vulgare L. is an important medicinal plant which is also used as a valuable spice. The present study was done to evaluate the ability of selenium accumulation of micropropagated O. vulgare under sodium selenate and/or salicylic acid treatment. Micropropagation of O. vulgare was done from shoot-tips as explants on modified Murashige & Skoog (MS) medium. After 1 month, rooted plantlets were transferred to modified Murashige & Skoog solidified medium containing sodium selenate (0, 25 and 50 µM) and/or salicylic acid (0 and 100 mgL−1). After 4 wk, growth, selenium accumulation, biochemical parameters and oxidative stress indicators were determined. The results showed that the plantlets were able to accumulate 16.1 µg g−1 DW and 28.27 µg g−1 DW selenium in shoots at 25 and 50 µM selenate sodium concentrations respectively. Both concentrations of selenium increased shoot dry weight, length of shoot and root, soluble sugars and total protein content, peroxidase and superoxide dismutase activity. On the contrary, malondialdehyde content decreased under selenium treatment. It was found that by increasing selenium concentration the content of total protein, H2O2 and antioxidant enzymes activity increased significantly. Application of salicylic acid in combination with selenium improved growth but did not affect on selenium accumulation. The obtained results can be considered as the first report of biofortification of O. vulgare under tissue culture technique.

Synthesis and Preliminary Biological Activity of Selenium Polysaccharides from Tussilago farfara L.

Tussilago farfara L. selenium polysaccharides (STFPs, similarly hereinafter) were prepared by Selenous acid salt method from Tussilago farfara L. polysaccharide (TFP, similarly hereinafter). Taking the selenium content of STFPs as an indicator, the synthesis process of STFPs was optimized using response surface methodology based on single factor experiments. The optimal synthesis process conditions obtained are: 90 °C, 12 hours, selenide reagent ratio of 1.2: 1, HNO3 volume fraction of 0.7%, and the average selenium content of STFPs measured under these conditions is 2.338 mg/g. Characterization was carried out by measuring the selenium content, molecular weight, infrared spectroscopy. The results of antioxidant experiments showed that the maximum clearance rate of DPPH· by the selenium polysaccharide from Tussilago farfara L. was 73.16%, which were higher than from Tussilago farfara L. polysaccharides.

Stained Glass Effect in Anodic Aluminum Oxide Formed in Selenic Acid.

A combination of the unique porous structure and physical and chemical properties of anodic aluminum oxide (AAO) makes it widely used in cutting-edge areas of materials science and nanotechnology. Selenic acid electrolyte provides the ability to obtain AAO with low porosity and high optical transparency and thus is promising for the preparation of AAO photonic crystals (PhCs). Here, we show the influence of crystallographic orientation of Al on the electrochemical oxidation rate in 1 M H2SeO4 as well as on the growth rate, porosity, and the effective refractive index of AAO. The cyclic anodization regime is used to prepare AAO PhCs with photonic band gaps, their wavelength positions are used to measure the AAO growth rate. At an anodization voltage of 40-45 V, the growth rate varies by up to 22.6% with crystallographic orientation of Al grains, causing the stained glass effect, which can be seen with the naked eye.

SYNTHESIS AND CHARACTERIZATION OF SELENIUM NANOPARTICLES STABILIZED WITH DIDECYLDIMETHYLAMMONIUM CHLORIDE

As part of this work, a synthesis procedure was developed and the characteristic of selenium nanoparticles stabilized with didecyldimethylammonium chloride (DDAC) was carried out. Nanoparticles were obtained by chemical reduction in an aqueous medium. Selenous acid was used as a selenium-containing precursor, ascorbic acid was used as a reducing agent, and didecyldimethylammonium chloride was used as a stabilizer. To determine the optimal parameters for the synthesis of selenium nanoparticles stabilized with didecyldimethylammonium chloride, a multifactorial experiment was carried out. The input parameters were the concentration of selenous acid, the concentration of didecyldimethylammonium chloride (DDAC) and the concentration of ascorbic acid. The average hydrodynamic radius of selenium particles, which was determined by the method of dynamic light scattering, was considered as an output parameter. The optimal parameters for the synthesis of selenium nanoparticles (R from 15 to 25 nm) have been established: reducing agent concentration – from 1.076 mol/l to 2.118 mol/l, stabilizer concentration – from 0.006 mol/l to 0.085 mol/l, precursor concentration – from 0.004 mol /l to 0.236 mol/l. At the next stage of research, the effect of solution pH on the average hydrodynamic radius of selenium nanoparticles was determined. It was shown that in the pH range from 1.81 to 2.21, the average hydrodynamic radius of selenium nanoparticles does not change significantly, which indicates the aggregative stability of selenium nanoparticles in this range. In the pH range from 2.21 to 4.56, there is a sharp increase in the average hydrodynamic radius from 21 to 497 nm. At pH ˃ 7.96, coagulation of selenium particles is observed.

Speciation of Selenium Nanoparticles and Other Selenium Species in Soil: Simple Extraction Followed by Membrane Separation and ICP-MS Determination.

The application of selenium nanoparticle (SeNP)-based fertilizers can cause SeNPs to enter the soil environment. Considering the possible transformation of SeNPs and the species-dependent toxicity of selenium (Se), accurate analysis of SeNPs and other Se species present in the soil would help rationally assess the potential hazards of SeNPs to soil organisms. Herein, a novel method for speciation of SeNPs and other Se species in soil was established. Under the optimized conditions, SeNPs, selenite, selenate, and seleno amino acid could be simultaneously extracted from the soil with mixtures of tetrasodium pyrophosphate (5 mM) and potassium dihydrogen phosphate (1.2 μM), while inert Se species (mainly metal selenide) remained in the soil. Then, extracted SeNPs can be effectively captured by a nylon membrane (0.45 μm) and quantified by inductively coupled plasma mass spectrometry (ICP-MS). Other extracted Se species can be separated and quantified by high-performance liquid chromatography coupled with ICP-MS. Based on the difference between the total Se contents and extracted Se contents, the amount of metal selenide can be calculated. The limits of detection of the method were 0.02 μg/g for SeNPs, 0.05 μg/g for selenite, selenate, and selenocystine, and 0.25 μg/g for selenomethionine, respectively. Spiking experiments also showed that our method was applicable to real soil sample analysis. The present method contributes to understanding the speciation of Se in the soil environment and further estimating the occurrence and application risks of SeNPs.

Single crystal analysis and DFT studies of the novel hybrid material-based on 2-hydroxypyridine and selenic acid

A novel hybrid material based on 2-hydroxypyridine and selenic acid, abbreviated as [(2-OH-pyH+)]2SeO4, has been synthesized using a slow evaporation method. The compound crystallizes in the centrosymmetric space group C2/c of the monoclinic system. Furthermore, theoretical studies are also performed at the B3LYP/6–31 + G* level to investigate the molecular structure, vibrational spectra, and optical properties of [(2-OH-pyH+)]2SeO4 compound, whereas the TD-DFT calculations are carried out to simulate the HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) on the one hand to achieve the frontier orbital gap and on the other hand to calculate the UV–visible spectrum of the compound in gas phase. In addition, inter and intramolecular charge interactions (NBO) as well as Molecular electrostatic potential (MEP) have also been computed.

The mechanism of the oxidation of narceine by means of selenous acid -sulphuric acid

The chemistry of selenous acid was misunderstood for many years, being explained by electron back donation. In this communication we disclose the reaction mechanism of the interaction of narceine with selenous acid in sulphuric acid. Narceine is a complex molecule that displays a carboxylic acid, a tertiary amine, a ketone, three methoxy groups and a benzodioxole; so, it was necessary select the principal reaction site. Although a methoxy group can be demethylated with the employed reagent since codeine gives the same violet colour obtained with morphine. The chemical deportment of the methylenedioxy ring in the presence of methoxy groups needed revision. It was found that the five-member ring is cleaved preferentially. Thus, a sustained reaction mechanism could be advanced. The reactive species is protonated selenous acid, which reacts with an oxygen of the cyclic group, water being eliminated. The oxonium ion is neutralized by ring opening in a concerted mechanism involving water reaction at the methylene. An organometallic intermediate is obtained, a selenite, and a hemiacetal. Finally, protonation of the selenium-oxygen double bond produces an acidolysis via a synchronous mechanism involving five electron shifts. This way selenium (II) hydroxide, an ortho-quinone and formaldehyde are obtained.

Protonated Organic Diamines as Templates for Layered and Microporous Structures: Synthesis, Crystal Chemistry, and Structural Trends among the Compounds Formed in Aqueous Systems Transition Metal Halide or Nitrate-Diamine-Selenious Acid.

Systematic studies of crystalline compounds formed in aqueous systems containing aliphatic diamines, divalent transition metal halides, and selenious acid resulted in the discovery of a large family of new complex species corresponding to several new structure types. With ethylenediamine (en), layered (enH2)[M(HSeO3)2X2] compounds are the most commonly formed species which constitute a significant contribution to the family of layered hydrogen selenites containing neutral [M(HSeO3)2] (M = Mg, Mn, Co, Ni, Cu, Zn, Cd) 2D building blocks. In contrast to some previous suggestions, piperazine (pip), as well as its homologue N-methylpiperazine, mostly give rise to quite different, sometimes more complex, structures of varied dimensionality while the (pipH2)[M(HSeO3)2X2] compounds are formed only with M = Cu and Cd. In addition, metal-, halide-, or selenium-free by-product species are observed. The SeIV can be present in a multitude of forms, including H2SeO3, HSeO3-, SeO32-, and Se2O52-, reflecting amazing adaptability to the shape of the templating cations.

Se-doped Nb2O5–Al2O3 composite-ceramic nanoarrays via the anodizing of Al/Nb bilayer in selenic acid

Novel arrays of Nb2O5-based ceramic nanostructures of various sizes (9–210 nm) and morphologies (dots, goblets, rods) aligned on substrates are fabricated via the anodizing of a thin Nb film through the initially formed porous anodic alumina (PAA) film in 1.5 M selenic acid (H2SeO4) – a new aqueous electrolyte generating extraordinarily thinner PAA pores than any other solutions. Accordingly, the nanostructures formed in the selenic acid are 1.3-fold thinner and better self-ordered than their counterparts formed from the same Al/Nb precursor bilayer in a reference oxalic-acid electrolyte. The nanostructures have a dual (core/shell) composition: the inner material (the core) is stoichiometric Nb2O5, whereas the outer layer (the shell) is a few nm-thick substoichiometric NbOx mixed with Al2O3. The composite-ceramic nanoarrays grow doped with selenium species such as selenate (SeO42−) and selenide (Se2−) anions originating from the electrolyte and migrating inward under the high electric field. The incorporated Se species do not contribute to photoluminescence emission nor hinder the Raman signal from the nanoarrays, which makes them highly promising as Nb2O5-based SERS biosensing substrates. The planar PAA-inbuilt Se-doped Nb2O5–Al2O3 nanostructured ceramic film performs like a high-k low-loss low-leakage-current dielectric promising for on-chip integration. More potential applications of the Se-doped ceramic nanoarrays developed here include biomedical antibacterial coatings, advanced superhydrophobic surfaces, gas-sensing, and catalytic layers.

Comparison of Selenic Acid and Pyruvic Acid-Loaded Silver Nanocarriers Impact on Colorectal Cancer Viability.

Colorectal cancer (CRC) is a leading cause of morbidity and death worldwide. As current cancer drugs are ineffective, new solutions are being sought in other fields, including nanoscience. Similarly, silver nanoparticles play an important role in the pharmaceutical industry as they act as anti-cancer agents with less harmful effects and are usually 1 to 100nm in size. Selenic acid (SA) and pyruvic acid (PA) are involved in various metabolic pathways in cancer. For this reason, we decided to detect their influence on colorectal cancer using silver-based (Ag) nanocarriers. DLS, Zetasizer, SEM and UV-Vis analyses were used to characterize AgSA and AgPA. A UV spectrophotometer was used to analyze the release of the NPs. MTT analyses were used to measure the viability of HCT116 and HUVEC cells, and IC50 values were calculated using GraphPad Prism. The indicated dosage and particle size of AgSA NPs proved to be suitable for cytotoxicity. Moreover, injection of these nanoparticles into non-cancer cells proved safe due to their minimal toxicity. In contrast, the AgPA NPs have no cytotoxicity and induce proliferation of HCT116 cells. Finally, only the synthesised AgSA nanoparticles could be used for advanced cancer therapy, which is both inexpensive and has minimal side effects.

Photocatalytic degradation of dyes in aqueous media by gum shellac stabilized selenium nanoparticles

Abstract The present work outlines the successful synthesis of selenium nanoparticles (Se NPs) stabilized with gum shellac (GS) and their use as photocatalyst for the enhanced degradation of dyes. Se NPs were synthesized by a simple and cost effective chemical reduction method using selenious acid, GS and sodium borohydride. Gum shellac was used as stabilizing agent. The orange red gum shellac-selenium nanoparticles (GS–Se NPs) were characterized by UV–Vis spectroscopy, Fourier transform infra-red (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The morphology of these particles appeared to be uniform and spherical as observed in SEM images. Energy dispersive X-ray spectroscopic profile showed the presence of elemental selenium, carbon and oxygen. The synthesized GS–Se NPs were investigated for their photo-catalytic efficiency towards degradation of methylene blue (MB) and methyl orange (MO) dye in aqueous media. Absorbance was measured at λ max 665 nm and 455 nm for MB and MO, respectively. Maximum degradation of MB in-comparison with MO obtained at 50 mg/L were 81.72 % and 71.42 % respectively. A very slow degradation rate was observed for the MO and MB in the absence of synthesized photocatalyst whereas greater percentage degradation was observed for the GS–Se NPs.

Green Production and Characterization of Silver Selenide Nanoparticles Using the Cladosporium sp. ssf15 Cell-free Extract

Background: Chalcogenide nanoparticles (NPs), such as silver selenide NPs (Ag2Se NPs), are used as quantum dots in pharmaceutical formulations for the detection of cancer cells, as well as in solar cells, sensors, and electrical, optical, and magnetic instruments. Objectives: The physical-chemical production of metal NPs is expensive and difficult and pollutes the environment due to the use of dangerous chemicals and by-products. Hence, green chemistry-based processes must be developed as a reliable alternative. This study investigated indigenous aquatic fungal isolates for Ag2Se NP synthesis. Methods: Visual examination, UV-Vis spectroscopy, scanning electron microscopy (SEM), dynamic light scattering (DLS) analysis, and energy-dispersive X-ray spectroscopy (EDX) tests confirmed the synthesis of Ag2Se NPs. Based on the characteristics of the colony, the microscopic features, and the polymerase chain reaction (PCR) amplification of the ITS1-5.8S-ITS2-ITS4 areas, the selected fungal isolate’s identity was established. Results: The SEM analysis revealed that Cladosporium sp. ssf15 produced spherical Ag2Se NPs with an average diameter of 37.84 nm. The average size of NPs synthesized by the fungal isolate was determined to be 40.92 nm using the DLS analysis, and the polydispersity index (PDI) was determined to be 0.26. Based on the results, regular spherical Ag2Se NPs with correct dispersion distribution were produced using 2 mM AgNO3 and 1mM selenious acid (H2SeO3). Conclusions: The results of this research have the potential to contribute to the development of a biocompatible approach and innovative research methods for investigating the green synthesis of Ag2Se NPs using fungal isolates.

Antimicrobial and Photocatalytic Activities of Selenium Nanoparticles Synthesized from Elaeagnus indica Leaf Extract

Selenium nanoparticles (Se NPs) have recently received much interest due to their low toxicity, high bioavailability, and wide applications. This study synthesized Se NPs using selenious acid as a starting material and leaf extract from Elaeagnus indica as a reducing agent. Spectroscopic and electron microscopy investigations have demonstrated the production of aggregated amorphous Se NPs with phytochemicals. Furthermore, the reduction of selenious acid into Se NPs by phytochemicals present in the leaf extract of E. indica was confirmed in a prominent band at 269 nm in the UV-visible spectrum. The biosynthesized selenium nanoparticles have a 10–15 nm particle size distribution. The agar well diffusion assay exhibited remarkable dose-dependent, wide-spectrum antimicrobial efficacy of the Se NPs against all the tested microorganisms. Moreover, the lowest minimum inhibitory concentration (10 µg/mL) was noted against Salmonella Typhimurium and Fusarium oxysporum. The prepared Se NPs degraded methylene blue dye by about 89% after 6 h of exposure to sunlight. In conclusion, the synthesis of Se NPs using E. indica leaf extract shows promise as a method for producing Se NPs with significant antimicrobial activity and potential for methylene blue photodegradation. These properties make them potentially valuable in various fields, including water treatment and biomedical applications, in the future.

Green Synthesis Optimization and Characterization of Selenium Nanoparticle Using Aqueous Extract of Peel Solanum Melongena L.

Recently, employing vegetable peel waste in green biosynthetic methods has received increased attention. It has low toxicity levels, is safe for the environment, and is simple to produce. The purpose of this research was to develop a sustainable technique of synthesizing SeNPs from an aqueous extract of eggplant peel. Because of this, selenium nanoparticles were produced in a single step utilizing an aqueous extract of peel Solanum melongena L. as a reducing and capping agent. The nanoparticles, which were studied using UV-Vis spectroscopy, had a surface Plasmon resonance centered at 320 nm. Nanoparticles sized between 50 and 150 nm were observed using a scanning electron microscope, while X-ray diffraction patterns revealed their amorphous, face-centered structure. Current research looks into how optimizing factors like reaction time, temperature, pH, selenous acid concentration, and reactant mixing ratio affect the quality of produced selenium nanoparticles. We found that 30 mM selenous acid, 30 degrees Celsius, pH 4, 9 days of incubation, and a 2:10 ratio of aqueous extract to selenous acid produced the highest quality selenium nanoparticles.

Shortening the sulfur cell cycle by a green approach for bio-production of extracellular metalloid-sulfide nanoparticles

In the present study, a new approach was introduced regarding the extracellular synthesis of selenium sulfide micro/nano-particles using Saccharomyces cerevisiae in different ammonium sulfate supplementation and in the presence of sodium selenosulfate precursors (S1) and a blend of selenous acid and sodium sulfite (S2). In S1, only cell supernatant exposed to ammonium sulfate was able to reduce sodium selenosulfate. Whereas, in S2, cell supernatant in both pre-conditions of with or without ammonium sulfate (S2 + or S2−) were able to reduce selenous acid and sodium sulfite. Electron microscopy, also indicated that selenium sulfide NPs were successfully synthesized with average size of 288 and 332 nm for S2 + and S2− in SEM and 268 and 305 nm in TEM. Additionally, elemental mapping by energy-dispersive x-ray analysis confirmed the presence of sulfur/selenium elements in the particles in a proportion of 24.50 and 23.31 for S2− and S2 + , respectively. The mass spectrometry indicated the probability of Se2S2, SeS1.1, Se2, Se, SeS5, SeS3, Se3S5/Se5, Se3/SeS5, Se6, Se4/SeS7, Se2.57S5.43/Se2S2 and Se4S/Se2S6 molecules for S2 + and of Se, Se2, Se3S5/Se5, Se6 and Se4 species for S2−. In FTIR spectra, primary (i.e. 1090–1020 and 1650–1580 cm−1) and secondary (1580–1490 cm−1) amine bands duly confirmed the protein corona around the NPs.