UV Vis Spectral Analysis Research Articles

Supramolecular complex catalyzed green synthesis of 9-(2-Ethylhexyl) carbazole: Structural, optical and DFT investigations

Green chemical principles such as (a) bio-renewable solvent utilization, (b) phase transfer catalysis (c) coloumn chromatography free methodologies, and (d) mild reaction conditions (i.e., room temperature, open atmosphere enough to carry out alkylation of carbazole) were optimized during the synthesis of 9-(2-Ethylhexyl) carbazole. High yield of title compound (96 %) was achieved with 1.0 equivalents of base NaOH and catalytic amount (0.1 equivalents) of 18C6 using a combination of 2-MeTHF and water green solvents. Structure of the Carbazole, 9-(2-Ethylhexyl)carbazole was conformed by analyzing the spectral data such as NMR, IR and Mass. DFT studies were explored to analyze various energy components and reactivity descriptors of the title product. The energy gap in between HOMO and LUMO of the this compound is found to be -4.59ev. Further, UV–Visible spectral analysis has been carried out in various solvents in different molarities to understand the stability of the compound with respect to various wavelength points. The increment of dielectric constant of the solvent (from 1,4 Dioxane to Acetonitrile in upward direction) also indicates major blue side shift. These studies are expected to offer critical insight into the correlation between structural, optical parameters.

A lawsone based novel disperse dyes with DHPMs scaffold: dyeing studies on nylon and polyester fabric

Zn acetate is an efficient catalyst for the synthesis of novel 3,4-dihydropyridine-2(1H)-ones (DHPMs) scaffolds via a triple cascade Biginelli reaction among polynuclear carbaldehyde, lawsone, and thiourea. All newly prepared compounds were confirmed by various spectral analysis. UV–visible spectral analyses were performed to study their intense depth of color. Prepared dyes were evaluated for dyeing performance on nylon and polyester fabrics, including the wash, light, rubbing and sublimation fastness. A color assessment, determination of percentage exhaustion, and fixation properties were also investigated. Results of all these studies were compared with lawsone, which is one of the starting materials for the synthesis of all these new disperse dyes. It has been observed that the prepared novel dyes greatly impacted their dyeing properties on both fabrics compared to lawsone. They have shown brilliant shades, higher affinity, superior tinctorial strength, and higher adsorption capacity than the lawsone. This report reveals the significance of prepared disperse dyes with great application value for nylon and polyester fibers.

Grewia tenax bark extract mediated silver nanoparticles as an antibacterial, antibiofilm and antifungal agent

Grewia tenax plant possesses many medicinal qualities that can be harnessed for bio-applications via nanotechnology in a cost-effective and environment-friendly manner. The synthesised silver nanoparticles (GTB-AgNPs) from Grewia tenax bark extract were first detected by observing the change in colour from yellowish brown to dark brown and confirmed by UV–vis spectroscopy. UV–vis spectral analysis recorded the surface plasmon resonance at 420 nm. In the current research, several process parameters (time, temperature, concentration of AgNO3 and the ratio of extract to AgNO3) were adjusted by using one variable at a time (OVAT) approach. Spectroscopy accompanied by dynamic light scattering (DLS), x-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive x-ray (EDX) determines the size, nature, morphological variations and chemical constituents of GTB-AgNPs. The size range was found within 35−45 nm and the image clearly showed that the GTB-AgNPs were spherical in shape and well dispersed in nature. Zeta potential and Fourier-transform infrared spectroscopy (FTIR) were done to analyse GTB-AgNPs stability, dispersion and the biomolecules in aqueous bark extract liable for the bioreduction of silver particles. These GTB-AgNPs showed excellent antibacterial action against Gram-positive (S. aureus and B. subtilis) and Gram-negative bacteria (P. aeruginosa and E. coli) which was observed by disc diffusion assay. Congo red agar plate (CRA) assay effectively unveiled the antibiofilm proficiency of the particles. These studies displayed a reduction in bacterial sustainability and the formation of exopolysaccharides. Disc diffusion assay confirmed the antifungal competency against A. niger and C. albicans. SEM was performed to elucidate the intracellular breakage and morphological transformations in cells of Gram-positive bacteria and fungi after treatment with GTB-AgNPs. The current study, therefore, enlightened applications of GTB-AgNPs as an efficient antimicrobial agent and applicable substitute in the pharmaceutical area.

Phytochemical Profiling for Leaf, Stem, Roots, and Seeds of Withania somnifera (L.) Dunal

Background: Withania somnifera (L.) Dunal, belonging to the Solanaceae family and commonly known as Ashwagandha, is a traditional Ayurvedic herb renowned for its adaptogenic properties. It plays a significant role in various classical Ayurvedic formulations and proprietary medicines. Traditionally, the roots of the plant are utilized over the aerial parts, such as leaves and stems. In recent years, a global increase in the use of Ashwagandha roots has been spurred by several modern pharmacological studies supporting its benefits. Methods: This study examined different parts of the herb, including leaves, stems, roots, and seeds, using methods like phytochemical analysis, thin layer chromatography (TLC) analysis, high-performance thin layer chromatography (HPTLC) phytochemical profiling, UV-visible spectral analysis, and 1H nuclear magnetic resonance (NMR) profiling. Results: The findings indicated that phytosterols, triterpenoids, and alkaloids were predominantly found in the leaves and stems, with lower concentrations in the roots and seeds. Ethanol extracts were particularly rich in total flavonoids, whereas aqueous extracts contained higher levels of phenolic compounds. High-performance thin layer chromatography fingerprinting varied for each part of the herb, effectively separating pigment-based components such as chlorophyll at 366 nm in the aerial parts. The 1H NMR spectra showed distinct metabolite profiles for each part of the plant. Conclusions: The analytical methods proposed in this study offer enhanced quality control and evaluation for the medicinal use of W. somnifera roots and its aerial components.

Amphiphilic nanofibrillated cellulose/polyurethane composites with antibacterial, antifouling and self-healing properties for potential catheter applications

This study focuses on enhancing interventional medical devices, specifically catheters, using a novel composite material. Challenges like corrosion and contamination in vivo, often caused by body fluids' pH, bacteria, and proteins, lead to mechanical damage, bacterial colonization, and biofilm formation on devices like catheters. The objective of this study was to prepare a versatile composite (HFs) by designing polyurethanes (HPU) with an ionic chain extender (HIID) and blending them with amphiphilic nanofibrillated cellulose (Am-CNF). The composite leverages dynamic interactions such as hydrogen bonding and electrostatic forces, as evidenced by Molecular Mechanics (MM) calculations. The H4F0.75 composite exhibited exceptional properties: 99 % length recovery post 600 stretching cycles at 100 % strain, rapid self-healing in artificial urine, high bactericidal activity, and excellent cell viability. Moreover, mechanical aging tests and UV–vis spectral analysis confirmed the material's durability and safety. These findings suggest that the HFs composite holds significant promise for improving catheters' performance in medical applications.

Experimental and theoretical interpretations of structural, optical, mechanical and thermal properties of 2-aminopyridinium phthalate single crystals

Nonlinear optical good quality single crystals of 2-aminopyridinium phthalate single crystals are synthesized by solution growth technique. Structural parameters are elucidated by Single Crystal X-ray diffraction method which reveals that the material crystallizes in non-centrosymmetric crystalline framework. Vibrational assignments are interpreted by Fourier Transform Infrared spectral analysis. The thermal, mechanical and laser stability are explored by TG/DTA, microhardness and Laser Damage threshold analysis. The material has good emission nature in the violet emission region. The linear optical properties are elucidated with the help of UV–visible spectral analysis. The intermolecular charge transfer interactions are analyzed by HOMO-LUMO and MESP maps by using Gaussian ’09 software program. The second harmonic generation efficiency of the synthesized material are predicted by Kurtz Perry powder technique.

Experimental and Theoretical Insight into the Ionic Liquid-Mediated Complexation of Trivalent Lanthanides with β-Diketone and Its Fluorinated Analogue.

A multitechnique approach with theoretical insights has been employed to understand the complexation of trivalent lanthanides with two β-diketones, viz. 1-phenyl-1,3-butanedione (L1) and 4,4,4-trifluoro-1-phenyl-1,3-butanedione (L2), in an ionic liquid (C6mim·NTf2). UV-vis spectral analysis of complexation using Nd3+ revealed the predominance of ML2+ and ML4- species. The stability constants for the PB complexes were higher (β2 ∼ 10.45 ± 0.05, β4 ∼ 15.51 ± 0.05) than those for the TPB (β2 ∼ 7.56 ± 0.05, β4 ∼ 13.19 ± 0.06). The photoluminescence titration using Eu3+ corroborated the same observations with slightly higher stability constants, probably due to the higher ionic potential of Eu3+. The more asymmetric (AL2ML4 ∼ 5.2) Eu-L2 complex was found to contain one water molecule in the primary coordination sphere of Eu3+ with more covalency of the Eu3+-O bond (Ω2L1 = 8.5 × 10-20, Ω4L1 = 1.3 × 10-20) compared to the less asymmetric Eu-L1 complex (AL1ML4 ∼ 3.5) with two water molecules having less Eu-O covalency (Judd-Offelt parameters: Ω2L1 = 7.3 × 10-20, Ω4L1 = 1.0 × 10-20). Liquid-liquid extraction studies involving Nd3+ and Eu3+ revealed the formation of the ML4- complex following an 'anion exchange' mechanism. The shift of the enol peak from 1176 to 1138 cm-1 on the complexation of the β-diketones with Eu3+ was confirmed from the FTIR spectra. 1H NMR titration of the β-diketones with La(NTf2)3 evidenced the participation of α-H of the β-diketones and protons at C2, C4, and C5 positions of the methylimidazolium ring. For the ML2 complex, 4 donor O atoms are suggested to coordinate to the trivalent lanthanides with bond distances of 2.3297-2.411 Å for La-O, 2.206-2.236 Å for Eu-O, and 2.217-2.268 Å for Nd-O, respectively, while for the ML4 complex, 8 donor O atoms were coordinated with bond lengths of 2.506-2.559 Å for La-O, 2.367-2.447 Å for Eu-O, and 2.408-2.476 Å for Nd-O. The Nd3+ ion was higher by 9.7 kcal·mol-1 than that of the La3+ ion for the 1:4 complex. The complexation energy with L1 was quite higher than that with L2 for both 1:2 and 1:4 complexes. Using cyclic voltammetry, the redox behavior of trivalent lanthanides Eu and Gd with β-diketonate in ionic liquid medium was probed and their redox energetic and kinetic parameters were determined.

Tripodal receptor cross-linked polymer as a promising adsorbent for iodine vapor capture and adsorption from water

A cross-linked tripodal receptor polymer was synthesized using a Friedel-Crafts polymerization reaction which showed an iodine vapor capture capacity of 2.47 g g−1 at 80 °C with remarkable iodine adsorption per unit BET surface area of 86 wt/(m2/g). UV–Vis spectral analysis confirmed that the polymer adsorbent rapidly adsorbs iodine from water. Importantly, the polymer exhibited reversible iodine adsorption allowing the polymer to be reused several times without losing the adsorption efficiency. We also investigated the adsorption capability of the synthesized polymer TPP as a filtration material for practical applications. Through dynamic adsorption experiments using a syringe pump setup, we demonstrated that a mere 40 mg of the TPP polymer effectively purifies 20 ml of a 2.5 mM aqueous iodine solution. Our findings underscore the exceptional adsorption efficiency of the TPP polymer, as evidenced by the successful removal of iodine molecules from the solution. These results not only highlight the potential of the TPP polymer for its utility in environmental remediation applications particularly for the treatment of effluents from nuclear reactors.

Investigation of an aminothiazole-based scaffold as an anti-inflammatory agent: Potential application in the management of cytokine storm in SARS-CoV-19

Aminothiazole-based structures, including compounds like anakinra, nitazoxanide, amiphenazole, and tizoxanide, along with cytokine-blocking agents such as tocilizumab and siltuximab are currently under extensive investigation for their potential in managing severe COVID-19 by specifically targeting and inhibiting cytokines responsible for cytokine release syndrome (CRS). These targeted therapies have shown promising results in effectively mitigating the effects of severe COVID-19. Herein, we carried out a biological assessment of a novel aminothiazole-based derivative 5-(phenylthio)-4-(2-(trifluoromethyl) phenyl) thiazol-2-amine (X22) to gauge its potential as an anti-inflammatory agent. Utilizing in vitro assays, which included measuring nitric oxide (NO) inhibition and observing the production of LPS-induced pro-inflammatory cytokines (TNF-α and IL-6) in RAW 264.7 macrophages. Furthermore, the X22 was characterized by experimental FT-IR, NMR, and UV–visible spectral analysis. The optimized molecular geometry and vibrational wave numbers were calculated using the DFT and B3LYP/6–311++G (d,p) basis set. The vibrational assignments were calculated using VEDA's Potential Energy Distribution (PED) program. 1H and 13C NMR were calculated by the GIAO method. Additionally, compounds HOMO-LUMO and HF interactions were studied. Subsequently, the MEP map was traced to find the reactive sites of X22. In addition, Mulliken population analysis and thermodynamic properties with respect to various temperatures were also calculated. All the theoretical predictions were carried out by using the DFT-B3LYP method at the level of 6–311++G (d,p). Finally, the molecular docking interactions revealed that ligand (X22) binds to TNF-α and IL-6 via H-bonding with amino acids Tyr 151, Ser60, Gln61, and Arg179. These findings suggest that X22 could be a valuable therapeutic agent for mitigating the progression of severe SARS-CoV-2 infections.

Semi-empirical design and synthesis of novel 4-hydroxy-6-sulphonaphthyl azohydroxynaphthalenes with predominant hydrazone form

Due to their enhanced photochromic effects, hydrazone forms of tautomeric azo compounds are commercially preferred as photoreceptors and binary switches. While ortho-hydroxyazo compounds readily exhibit an intramolecular hydrazone re-arrangement, the predominance of hydrazone tautomers of para-hydroxyazo compounds is less frequently observed. The objective of this study was to design and synthesize sulphonated 4-naphthylazo naphth-1-ols with preferential hydrazone shift.PM6 calculations were used to quantify contributions of selected structural features to hydrazone stability in a set of model compounds. Synthesis of five computationally-optimized compounds (3a-e) was subsequently carried out via diazo coupling of 5‑hydroxy-7-sulphonaphthalene-2-diazonium ion with naphthol derivatives. The azo-hydrazone equilibria of 3a-e were further characterized using spectroscopic techniques and density functional theory (DFT).Computational design revealed that sulphonic acid substitution on the coupling components of the dyes and, solvation effect of the substituents were the highest contributors to hydrazone shift of the compounds. The ring position and electron withdrawing resonance effect of substituents were less contributory. Increasing substitution with sulphonic acid or another hydrophilic group (amino) also resulted in higher hydrazone stability. Mass spectral, IR and NMR data confirmed computational results with mono sulphonated 3a and poly substituted 3c-e existing predominantly as azo and hydrazone forms respectively. UV–Visible spectral analysis revealed that azo and hydrazone forms of 3a predominated in hydrogen bond acceptor and donor solvents respectively. In contrast, absorption spectra of 3b-e showed lone hydrazone bands in all solvents investigated. The DFT/M06-2X/6-31G(dp) characterization of the azo-hydrazone equilibrium of the compounds confirmed experimental results and showed that hydrazone tautomers of 3b, 3c and 3d were more stable than corresponding azo forms by 1.536, 0.289 and 1.359 kcal/mol respectively. DFT also confirmed involvement of sulphonic acid and imino groups in the transition of the dyes’ structures to the keto form.Three novel p-hydroxyazo dyes with increased hydrazone stability have been synthesized.

Crystal growth and vibrational spectroscopic studies on the novel NLO active 2-amino-4-methylpyridinium fluoroborate single crystal by experimental and computational technique

A semi-organic non-linear optical (NLO) single crystal of 2-amino-4-methylpyridinum fluoroborate(2AFB) to be synthesized and characterized via single crystal X-ray diffraction technique (SXRD), UV–Vis, FTIR and FT-Raman spectra. The quantum chemical calculations were carried out using density functional method (DFT) with B3LYP/6–31+G(D) basis set. The intermolecular interaction and stability of the title molecule have been obtained by NBO analysis. The molecular electrostatic potential and frontier molecular orbital analysis give a visual representation of charge distribution of the title molecule. The N-H…F interaction within 2AFB molecule was investigated via AIM and RDG analysis. The optical quality and energy band gap of 2AFB single crystal were found out using UV–visible spectral analysis. The emission spectra of the grown 2AFB single crystal has been examined by fluorescence spectral analysis. 2D fingerprint plot confirms the H…F and H…H interactions that exhibit the most significant contribution in crystal packing. The outcome of SXRD, UV-visible, HOMO-LUMO, NLO and Z-scan values were compared with earlier reported compounds and amongst which the analysed compound 2AFB shows good NLO activity. The NLO activity of the title molecule was confirmed theoretically and experimentally by DFT method and Z-scan technique.

Synthesis and characterization of novel uranyl clusters supported by bis(pyrazolyl) methane ligands: biomimetic catalytic oxidation, BSA protein interaction and cytotoxicity studies.

Two novel uranyl complexes were synthesized using bis-pyrazolyl methane ligands. The complexes were characterized by several spectroscopic techniques, including UV-Vis, IR, NMR, mass spectrometry, fluorescence, electrochemical, and thermogravimetric analysis. The solid-state structure of the complex C1 was determined with the help of single-crystal X-ray diffraction studies. The complexes C1 and C2 efficiently catalyse the oxidation of 3,5-di-tert-butyl catechol and 2-aminophenol in the atmospheric air, imitating the catalytic activity of the catechol oxidase and phenoxazinone synthase enzymes. The kinetic parameters and the catalytic efficiency (K cat/K M) of the reactions were calculated. Formation of organic free radicals in the catalytic reactions was confirmed by EPR spectroscopy. The interaction of these complexes with the protein, bovine serum albumin, was investigated by using UV-Vis and fluorescence spectral analysis. The cytotoxicity of the complexes against MDAMB-231 and A549 cell lines was investigated, and IC50 values were determined.

Calotropis procera (L.) mediated synthesis of AgNPs and their application to control leaf spot of Hibiscus rosa-sinensis (L.).

Nature is gifted with a wide range of ornamental plants, which beautify and clean the nature. Due to its great aesthetic value, there is a need to protect these plants from a variety of biotic and abiotic stresses. Hibiscus rosa-sinensis (L.) is an ornamental plant and it is commonly known as China rose or shoeblack plant. It is affected by several fungal and bacterial pathogens. Current study was designed to isolate leaf spot pathogen of H. rosa-sinensis and its control using silver nanoparticles (AgNPs). Based on molecular and morphological features, the isolated leaf spot pathogen was identified as Aspergillus niger. AgNPs were synthesized in the leaf extract of Calotropis procera and characterized. UV-vis spectral analysis displayed discrete plasmon resonance bands on the surface of synthesized AgNPs, depicting the presence of aromatic amino acids. Fourier transform infrared spectroscopy (FTIR) described the presence of C-O, NH, C-H, and O-H functional groups, which act as stabilizing and reducing molecules. X-ray diffraction (XRD) revealed the average size (~32.43 nm) of AgNPs and scanning electron microscopy (SEM) depicted their spherical nature. In this study, in vitro and in vivo antifungal activity of AgNPs was investigated. In vitro antifungal activity analysis revealed the highest growth inhibition of mycelia (87%) at 1.0 mg/ml concentration of AgNPs. The same concentration of AgNPs tremendously inhibited the spread of disease on infected leaves of H. rosa-sinensis. These results demonstrated significant disease control ability of AgNPs and suggested their use on different ornamental plants.

Unveiling the cytotoxic and anti-proliferative potential of green-synthesized silver nanoparticles mediated by Colletotrichum gloeosporioides.

Fungal endophytes are a putative source of bioactive metabolites that have found significant applications in nanomedicine due to their metabolic versatility. In the present study, an aqueous extract of the fungal endophyte, Colletotrichum gloeosporioides associated with a medicinal plant Oroxylum indicum, has been used for the fabrication of green silver nanoparticles (CgAgNPs) and further evaluated their cytotoxic and anti-proliferative activity. Bioanalytical techniques including UV-Vis spectral analysis revealed a sharp band at 435 nm and functional molecules from the aqueous extract involved in the synthesis of CgAgNPs were evidenced through FTIR. Further, the crystalline nature of CgAgNPs was determined through XRD analysis and microscopy techniques including AFM, TEM and FESEM demonstrated the spherical shape of CgAgNPs exhibiting a crystalline hexagonal lattice and the size was found to be in the range of 9-29 nm. The significant cytotoxic potential of CgAgNPs was observed against breast cancer cells, MDA-MB-231 and MCF-7 with IC50 values of 18.398 ± 0.376 and 38.587 ± 1.828 μg mL-1, respectively. The biochemical study revealed that the treatment of MDA-MB-231 and MCF-7 cells with CgAgNPs reduces glucose uptake, suppresses cell proliferation, and enhances LDH release, indicating reduced cell viability and progression. Moreover, our research revealed differential expression of genes associated with apoptosis, cell cycle inhibition and metastasis suppression, evidencing anti-proliferative activity of CgAgNPs. The main objective of the present study is to harness anti-breast cancer activity of novel biogenic nanoparticles synthesized using the aqueous extract of O. indicum associated C. gloeosporioides and study the underlying mechanistic pathway exerted by these mycogenic nanoparticles.

Growth and characterization of organic 2-methylbenzimidazole 4-Aminobenzoate Single crystal for Opto-electronic device applications

A new organic material of 2-Methylbenzimidazole 4-Aminobenzoate (2MIAB) with a size of 5 × 4 × 3 mm3 was grown by solvent evaporation solution growth method. The SCXRD studies reveal that the 2MIAB crystal has a monoclinic crystal structure and belongs to the space group P21/nn number is 4 unit cell parameters are a=7.8319(3) Å, b=20.6465(8) Å, c=9.0432(3) Å, α =90°, β =90.4140°, γ =90°and V =1462.26(9) Å 3. The hkl planes are identified through Powder XRD analysis. The functional groups present in the 2MIAB crystal were determined from FTIR spectral analysis. The UV–Vis spectral analysis of 2MIAB shows a high transmittance range of 99% and a cut-off wavelength of approximately 315 nm. The surface morphology of the 2MIAB compound is examined through FE-SEM analysis. The thermal studies reveal that the grown crystal is stable up to 134 °C. dielectric constant in free space (ϵ0) and dielectric loss (tanδ) of 2MIAB crystal at varying temperatures (313 K, 323 K, 333 K) are recorded with a frequency range of 50 Hz to 5 MHz. The load-dependent hardness of the 2MIAB crystal was analyzed using Vicker’s microhardness test. The optical limiting was performed by Q-switch Nd: YAG laser with a wavelength of 532 nm and intensity of 2.46×1012 W/m2 (pulse rate of 9 ns and energy of 100 μJ ). We employed First-principles density functional theory and ab-initio molecular dynamics simulations to study the electronic and optical properties of the 2MIAB material. We demonstrate that this material is semiconductor in nature, with an energy band gap of 3.26 eV and significant absorption in the UV light range.

Synthesis, Characterization, Biological Properties, ADMET and Drug-likeness Analysis of Mn (II) complexes with Schiff Bases Derived from Sulphathiazole and 4-diethylaminosalicyaldehyde/Salicyaldehyde

Mn (II) complexes were synthesized with the Schiff base ligand obtained by the condensation of sulfathiazole with 4-diethylaminosalicyaldehyde/Salicyaldehyde. Their characterization was performed by elemental analysis, molar conductance, melting points, magnetic susceptibility, infrared, and UV–Vis spectral analysis. The results suggest that the Schiff bases and their complex are synthesized in excellent yield, molar conductance studies on the complexes indicated they were non-electrolytic. The IR data indicated that the Schiff base ligand is tridentate coordinated to the metallic ion with two N atoms from the azomethine group and thiazole ring and one O atom from the phenolic group. The electronic spectral study showed octahedral geometry for all the complexes which are further supported by magnetic moment values. The ligand and its complexes were screened against four bacterial and two fungal strains using the disk diffusion method. The antimicrobial evaluation results revealed that the metal (II) complexes exhibited higher antimicrobial activity than the free Schiff base ligand. The ADMET and drug-likeness studies of the synthesized ligands indicated that the Schiff base ligands fulfill Lipinski’s, Ghoose, Veber, Egan, and Mugge rules but the complexes showed some deviations. They also displayed low toxicity levels.

Green synthesis of silver nanoparticles using Saccharum officinarum leaf extract for antiviral paint

Abstract In this study, silver nanoparticles (AgNPs) were synthesized via an eco-friendly approach using an extract from sugarcane leaves (Saccharum officinarum). The optimal synthesis conditions were determined to be a pH of 10, yielding AgNPs with an average size of 11.7 ± 2.8 nm. This was substantiated by UV-vis spectral analysis, transmission electron microscopy, and field emission transmission electron microscope coupling with selected area electron diffraction. The synthesized AgNPs exhibited notable antibacterial efficacy against two prominent pathogens, namely Staphylococcus aureus and Escherichia coli, with minimum inhibitory concentration values of 20 and 2.5 ppm, respectively. Further extending the applications of AgNPs, they were successfully integrated into architectural paints at varying concentrations to create antiviral coatings. The addition of AgNPs influenced several properties of the paints, including viscosity, hiding power, and color characteristics. Notably, our findings revealed that the antiviral paint containing 80 ppm of AgNPs effectively hindered virus propagation, exhibiting a remarkable reduction of over 90% when compared to the control, measured by 50% tissue culture infectious dose.

Evaluation of antimicrobial, anti-inflammatory and cytotoxic effects of silver nanoparticles synthesised from Cynodon dactylon

Plant mediated synthesis of metal nanoparticles (MNPs) has been considered as a reliable green technique for mitigating the involvement of toxic chemicals and which is widely used for desired applications. In the present study, a simple and environment friendly approach for the synthesis of silver nanoparticles (AgNPs) using the aqueous extract of Cynodon dactylon was proposed. The phytochemicals present in C. dactylon acted as the reducing as well as the capping agents during the nanoparticle synthesis. The aqueous extract of C. dactylon added to AgNO3 solution showed a colour change from brown to black at room temperature which confirmed the formation of AgNPs. UV-Vis spectral analysis revealed the surface plasmon resonance band of synthesised AgNPs at around 380 nm, while FT-IR spectroscopy confirmed the role of biomolecules present in the plant extract in the reduction and efficient stabilisation of AgNPs. The X-ray diffraction (XRD) patterns confirmed distinctive peaks corresponding to the crystalline planes of cubic silver. Shape and surface morphology of green AgNPs were examined by SEM. Biosynthesized AgNPs were predominantly cubical and spherical with an average particle size of 30.5 nm approximately as observed through SEM and DLS analysis respectively. The EDS analysis displayed intense signals of silver element. The stability of AgNPs was confirmed by zeta potential analysis. A negative zeta potential value of −17.1 mV indicated the stability and good dispersion of AgNPs. Antimicrobial and anti-inflammatory potentials of green synthesised AgNPs were analysed through in vitro techniques. The cytotoxic effect of green AgNPs on normal fibroblast cells (L929) was studied to analyse its effect on normal cells.

Insights into the structures and properties of dyes in the Fenton catalytic process for treating wastewater effluent.

A notable level of apprehension exists over the adverse impacts of dye pollution on aquatic ecosystems and human well-being. The primary objective of this research is to assess the effectiveness of Fenton catalytic reactions in degrading 14 different commercial azo dyes (both single and double) present in aqueous solutions. The investigation focused on the function of dye structures, using a combination of experimental data and examination of theoretical factors. Dye degradation process was carried out at pH 3, and the concentrations of Fe2+ (10-4 mol/L), H2 O2 (2 × 10-3 mol/L), and dye (0.05 g/L). The findings revealed that dyes with a larger molecular weight were more effective at degrading (D%), with the overall degradation efficiency varying from 0% to 94%. Functional groups played an important role in degradation efficiency; for example, dyes with higher aromatic rings led to less D%, while a higher number of sulfonic, methyl, and nitro groups was responsible for better D%. Notably, the presence of OH groups in the backbone of dyes (AB 24, ABE 113, and MB 9) formed the Fe complex during the catalytic process, and the D% was minimal. On the other hand, theoretical quantum calculations such as the greater the JCLogP, highest occupied molecular orbital, and Dipole moment value, the higher the degradation efficiency. And dyes with low lowest unoccupied molecular orbital tended to have a better degradation efficiency. To some extent, UV-Vis spectral analysis was investigated to determine the degradation pathway, and the pseudo-second-order kinetic model fitted better in the degradation process. The overall experimental and theoretical findings suggested that dye degradation efficiency by the Fenton process is structure-dependent. PRACTITIONER POINTS: Insights into the role of azo dye structures-properties on degradation efficiency. Higher molecular weight and sulfonic groups containing dyes showed better degradation efficiency. Hydroxyl groups play the formation of the Fe complex during the degradation process. Higher values of HOMO and lower values of LUMO enhanced degradation efficiency. The pseudo-second-order (PSO) kinetic model obeyed the Fenton process.

Exploring the antibacterial and antibiofilm potential of copper oxide nanoparticles biosynthesized using Centratherum punctatum leaf extract

This manuscript focuses on the eco-friendly synthesis of copper oxide nanoparticles (CuO NPs) using Centratherum punctatum leaf extract. FTIR analysis confirmed the presence of functional groups, while UV–vis spectral analysis exhibited absorbance peak at 224 nm. XRD analysis provided insights into the particle's crystallinity, revealing, crystal size in the range of 20–30 nm. SEM examination revealed the presence of spherical and hemispherical aggregated particles. The CuO NPs demonstrated potent antimicrobial activity and effectively inhibited biofilm formation by Pseudomonas aeruginosa. The environmentally friendly synthesis and promising antimicrobial and antibiofilm activities of CuO NPs make them noteworthy candidates for further exploration.