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Metal ion extraction and determination at trace level concentration are challenging due to sample complexity or spectral interferences. Herein, we prepared a through-hole aluminum oxide membrane (AOM) by electrochemical anodization of aluminum substrates. The prepared AOM was characterized by scanning electron microscopy, surface area analysis, porosity measurements, and X-ray photoelectron spectroscopy. The AOM with ordered nanopores was highly porous and possess inherent binding sites for selective arsenite sorption. The AOM was used as a novel sorbent for solid-phase microextraction and preconcentration of arsenite ions in water samples. The AOM’s sub-micrometer thickness allows water molecules to flow freely across the pores. Before instrumental determination, the suggested microextraction approach removes spectral interferents and improves the analyte ion concentration, with a detection limit of 0.02 μg L–1. Analyzing a standard reference material was used to validate the procedure. Student’s t-test value was less than critical Student’s t-value of 4.303 at a 95% confidence level. With coefficients of variation of 3.25%, good precision was achieved.

Lactoferrin is a heme-binding multifunctional glycoprotein known for iron transportation in the blood and also contributes to innate immunity. In this study, the interaction of theaflavin monogallate, a polyphenolic component of black tea, with camel milk lactoferrin was studied using various biophysical and computational techniques. Fluorescence quenching at different temperatures suggests that theaflavin monogallate interacted with lactoferrin by forming a non-fluorescent complex, i.e., static quenching. Theaflavin monogallate shows a significant affinity towards lactoferrin with a binding constant of ∼104–105 M−1 at different temperatures. ANS binding shows that the binding of polyphenol resulted in the burial of hydrophobic domains of lactoferrin. Moreover, thermodynamic parameters (ΔH, ΔS and ΔG) suggested that the interaction between protein and polyphenol was entropically favored and spontaneous. Circular dichroism confirmed there was no alteration in the secondary structure of lactoferrin. The energy transfer efficiency (FRET) from lactoferrin to theaflavin was found to be approximately 50%, with a distance between protein and polyphenol of 2.44 nm. Molecular docking shows that the binding energy of lactoferrin–theaflavin monogallate interaction was −9.7 kcal mol−1. Theaflavin monogallate was bound at the central cavity of lactoferrin and formed hydrogen bonds with Gln89, Tyr192, Lys301, Ser303, Gln87, and Val250 of lactoferrin. Other residues, such as Tyr82, Tyr92, and Tyr192, were involved in hydrophobic interactions. The calculation of various molecular dynamics simulations parameters indicated the formation of a stable complex between protein and polyphenol. This study delineates the binding mechanism of polyphenol with milk protein and could be helpful in milk formulations and play a key role in the food industry.

We report a graphene oxide (GO) lamellar membrane with increased inter-layer spacing for efficient permeation of water molecules and heavy metal ions through nanoporous graphene oxide. The inter-layer spacing of the GO sheets in the lamellar structure was increased by introducing poly-aminophosphonic acid (APA) in between the GO sheets. We demonstrate experimentally, the use of a prepared membrane (GO–APA) by a SPE technique for the preconcentration and extraction of heavy metal ions by chelate formation and their determination by ICP-OES. We found that this sub-micrometer-thick membrane allows unimpeded permeation of water molecules through two-dimensional capillaries formed across the pores and by closely spaced graphene sheets. Compared to the bulk GO sorbent, GO–APA membrane offers enhanced sensitivity and permeability for heavy metal ions due to relatively large inter-layer spacing and high surface area (extraction phase) with a high number of active functional groups. The potential of this technique for the preconcentration and extraction of Pb(II), Cd(II) and Cu(II) is illustrated with the contaminated ground water and industrial waste water analysis. The detection limit achieved for studied ions was 1.1 ng L−1, under optimized experimental conditions. The co-existing ions did not hinders the extraction of trace heavy metal ions. Accuracy of the developed method was assessed by analyzing Standard Reference Materials. The Student's t test values were found to less than the critical Student's t value of 4.303 at the 95% confidence level. The method shows good precision as coefficients of variation for five replicate measurements were found to be 4–5%.

Novel ruthenium arene complexes of flavonoid derivatives were synthesized and characterized. The structure of complex 1 was determined by single-crystal X-ray crystallography. Ruthenium complexes display strong DNA interactions. Zero-order relativistic approximation (ZORA) was employed for the B3LYP/DFT calculation to validate the structures of 2 and 3. Frontier molecular orbital (FMO) analysis was performed for getting a trend of DNA binding propensity of the complexes. The ruthenium complexes 1–3 were tested against pathogens, viz. Pseudomonas aeruginosa PAO1, Chromobacterium violaceum ATCC 12472, and methicillin-resistant S. aureus (MRSA). The ruthenium complexes exhibited potential acting as biofilm inhibitors and showed significant activity as quorum sensing inhibitors. Scanning electron microscopy (SEM) and confocal microscopy visualized biofilm inhibition, and a substantial reduction in microcolonies was observed. Furthermore, essential quorum sensing (QS) regulated functions that play a crucial role in biofilm formation were also studied, i.e., exopolysaccharide (EPS) production and swarming motility. A significant reduction was recorded at the tested sub-MICs.

In the present study, ecofriendly green synthesized ZnO/CuO nanorods were prepared by using the stabilizing and reducing characteristics of the alginate biopolymer. The bionanocomposite (BNC) material was characterized by various sophisticated analytical tools such as Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy-energy dispersive X-ray spectroscopy, transmission electron microscopy, UV-visible spectroscopy, differential scanning calorimetry, and the Brunauer-Emmett-Teller (BET) method. The composition of ZnO/CuO@Alg BNC was found to be C (16.16 ± 0.42%), O (42.26 ± 1.87%), Cu (31.96 ± 1.05%), and Zn (9.62 ± 0.48%), which also supports the approximate 3:1 ratio of Cu2+ and Zn2+ taken as the precursor. The nanocrystalline spinel ferrite was found to have a BET specific surface area of 19.24 m2 g-1 with a total pore volume of 0.075 cm3 g-1 and 1.45 eV as the band gap energy (E g). Further, the material was applied for the photodegradation of p-nitrophenol (PNP) under the advanced oxidative process (AOP) under visible sunlight irradiation. The visible light radiation was used for the degradation of PNP under pH 2 conditions and resulted in 98.38% of the photocatalytic efficiency of the ZnO/CuO@Alg catalyst within 137 min of irradiation time. The photocatalytic reaction was best defined by the pseudo-first-order kinetics which involves the adsorption of the PNP molecule on the surface of the catalyst, thereby demineralizing it in the presence of advanced active •OH radicals. The values of rate constant for the pseudo-first-order model (k 1) were calculated as 0.013, 0.016, 0.019, 0.021, and 0.023 min-1 with half-life periods of 53.31, 43.31, 36.47, 33.00, and 30.13 min for 10-50 mg L-1 PNP concentrations. The presence of t-butyl alcohol decreases the photocatalytic efficiency, which suggests that the degradation of PNP was accomplished by the •OH oxidative radical.

It is important to understand the nature and mechanism of interaction of drugs with serum albumins as such interactions govern their pharmacokinetics and pharmacodynamics. Plumbagin is a natural phytocompound, mainly present in the bark of Plumbaginaceae family plants and it has numerous therapeutic potentials. In this study, the interaction of plumbagin with human serum albumin (HSA) was deciphered using an array of biophysical and computational tools. The UV–vis spectroscopy established the formation of plumbagin-HSA complex with binding constant as 2.32 × 104 M−1. Fluorescence spectroscopy revealed that there was static mode of quenching of HSA’s fluorescence by plumbagin. The binding constant obtained by fluorescence spectroscopy was of the similar order as in case of UV–vis spectroscopy. The negative value of ΔH° (−3.67) indicated an endothermic nature of the reaction and negative value of ΔG° (−6.40 to −6.58) confirmed that complexation of plumbagin to HSA was spontaneous. There was nearly one binding site in HSA for plumbagin. Titration of plumbagin to HSA in presence of site-specific markers showed that plumbagin interacted at sub-domain IIA of HSA, commonly known as Sudlow’s site I. Moreover, the binding resulted in changes in microenvironment of tryptophan while of tyrosine residues remained approximately unchanged. This interaction also resulted in decrease of α-helical content of the studied serum protein. FRET calculations revealed that distance between plumbagin and HSA’s fluorophore (Trp214) was 2.27 nm. Finally, molecular docking studies substantiated the in vitro finding. Plumbagin formed hydrogen bond with Lys199 and Arg257 of HSA. Additionally, Arg222, His242, and Ala261 interacted via van der Waals forces and Leu238, Leu260, Ile264, Ile290, and Ala291 of HSA interacted with plumbagin through hydrophobic forces.

Herein, different types of metal-containing ionic liquid (IL) complexes and various metal oxide-based nanocatalysts have been successfully prepared (from ionic liquids) and applied for the oxidative desulfurization (ODS) of dibenzothiophene (DBT). The ILs complexes are comprised of N,N′-dialkylimidazolium salts of the type [RMIM-Cl]2[MCln], where [RMIM+] = 1 alkyl-3-methylimidazolium and M = Mn(II)/Fe(II)/Ni(II)/Co(II). These complexes were prepared using an easy synthetic route by refluxing the methanolic solutions of imidazolium chloride and metal chlorides under facile conditions. The as-prepared complexes were further used as precursors during the ionothermal and chemical synthesis of various metal oxide-based nanocatalysts. The resulting ILs salts and metal oxides NPs have been characterized by FT-IR, TGA, XRD, SEM, and TEM analysis. The results indicate that thermal and chemical treatment of ILs based precursor has produced different phases of metal oxide NPs. The calcination produced α-Fe2O3, Mn3O4, and Co3O4, NPs, whereas the chemical treatment of the ILs salts have led to the production of Fe3O4, Mn2O3, and α-Co(OH)2. All the as-prepared salts and metal oxide-based nanocatalysts were used as catalysts towards ODS of dibenzothiophene. The oxidation of dibenzothiophene was performed at atmospheric conditions using hydrogen peroxide as the oxygen donor. Among various catalysts, the thermally obtained metal oxide NPs such as α-Fe2O3, Mn3O4, and Co3O4, have demonstrated relatively superior catalytic activities compared to the other materials. For example, among these nanocatalysts, α-Fe2O3 has exhibited a maximum conversion (∼99%) of dibenzothiophene (DBT) to dibenzothiophene sulfone (DBTO2).

Enterohemorrhagic Escherichia coli infection is associated with gastrointestinal disorders, including diarrhea and colorectal cancer. Although evidences have established the involvement of E. coli in the growth of colon cancer, the molecular mechanisms of carcinogenesis of cancer growth and development are not well understood. We analyzed E. coli protein targeting in host cell organelles and the implication in colon cancer using in silico approaches. Our results indicated that many E. coli proteins targeted the endoplasmic reticulum (ER), ER membranes, Golgi apparatus, Golgi apparatus membranes, peroxisomes, nucleus, nuclear membrane, mitochondria, and mitochondrial membrane of host cells. These targeted proteins in ER, Golgi apparatus, peroxisomes, nucleus, and mitochondria may alter the normal functioning of various pathways including DNA repair, apoptosis, replication, transcription, and protein folding in E. coli-infected host cells. The results of the current in silico study provide insights into E. coli pathogenesis and may aid in designing new preventive and therapeutic strategies.

The green mechanism for the synthesis of nanoparticles and their application to the wastewater treatment is of inordinate curiosity to the research community. Herein we outline a novel method for the synthesis of silver nanoparticles via a green route using alginate-guar gum blend (GG-Alg@Ag) and their application to degrade methylene blue (MB) dye. The synthesized material was characterized by FTIR, XRD, SEM-EDX, TEM, TGA-DTG, AFM, and UV-vis techniques. A combination of RSM and CCD was employed to compute the system and optimized values of various interacting parameters such as exposure time (120 min), pH (4.98), dye concentration (194 mg L−1), and catalyst dose (0.07 g) with a photodegradation capacity of 92.33% and desirability 1.0. The mechanism of degradation reaction was best elucidated by the pseudo-second-order model suggesting chemical deposition of MB on the GG-Alg@Ag surface through followed by the reduction mechanism in the occupancy of visible light. The optical studies indicated a value of 2.5 eV by Tauc's plot for bandgap energy (Eg) for GG-Alg@Ag bionanocomposite.

A series of phenanthroimidazole (PI) derivatives (M1–M3): 2-phenyl-1H-phenanthro [9,10-d]imidazole (M1), 2-anthryl-1H-phenanthro[9,10-d]imidazole (M2), and 2-pyrenyl-1H-phenanthro[9,10-d]imidazole (M3) were synthesized and characterized using various spectroscopic techniques. The fluorescence quenching studies or sensing properties of the molecules M1–M3 with picric acid (PA) were studied. The molecules (M1–M3) exhibit strong fluorescence with a peak emission wavelength at 386, 486 and 456 nm. This emission gets quenched with the addition of PA. The mechanism of fluorescence quenching involves proton transfer from PA to M in the ground state, followed by the formation of a complex between the cation (M+) and picrate anion (PA−). The proton transfer breaks the conjugation inside the imidazole ring which in turn leads to loss of fluorescence. The proof of proton transfer was evident from the single X-ray crystal structure of the co-crystals (M1+–PA− and M3+–PA−) and their Hirshfeld surface analysis. Time-resolved fluorescence measurements reveal that quenching is static. The complex formation constant (Ks) and life-time for all the molecules are measured.

Current exanimation reports, green fabrication of silver doped TiO2 nanoparticles (Ag/TiO2) using aqueous extract of Acacia nilotica as bio-reductant and assess its potential as antimicrobial and anticancer agent. The obtained spherical Ag/TiO2 were characterized by various analytical techniques including FTIR, (XRD), (FE-SEM EDS), and (TEM). Synthesized Ag/TiO2 demonstrated broad spectrum antibacterial and anticandidal activity. The order of antimicrobial activity was found to be E. coli > C. albicans > MRSA > P. aeruginosa. In addition, cytotoxicity and oxidative stress of Ag/TiO2 nanoparticles in (MCF-7) cells was also investigated. Outcomes of MTT assay showed concentration dependent reduction in cell viability. Further, synthesized NPs reduced the level of glutathione, induced ROS generation and lipid peroxidation in the treated cells. Therefore, it is envisaged that these spherical nanoparticles may be exploited in drug delivery, pharmaceutical, and food industry. Keywords: Green synthesis, Ag/TiO2, Antimicrobial activity, Anticancer activity, MCF-7, Oxidative stress

Multi-drug resistance (MDR) poses a serious threat in the management of infectious diseases. Slow development of antibiotics and acquirement of resistance mechanisms has led the researchers to focus on development of novel chemotherapeutic agents with broad-spectrum activity having multiple sites of action. Till date, nanoparticles are proven to be a good alternative in management of MDR at least under laboratory conditions. In this study, dextrin was used for eco-friendly green synthesis of silver nanoparticles grafted by poly (methyl methacrylate). The nanoparticles were characterized using UV–vis spectroscopy, FTIR, XRD, SEM, EDX and TEM. The synthesized nanoparticles (PMMA-g-Dex@Ag) were then evaluated for antimicrobial and antibiofilm efficacy on multi-drug resistance bacterial and fungal pathogens. PMMA-g-Dex@Ag proved to be good bacteriostatic even at 4 μg/ml. The minimum inhibitory concentration (MIC) against C. albicans was found to be 16 μg/ml. Moreover, the biofilms of all tested pathogens were reduced by approximately more than 70% in presence of highest tested sub-MIC. Inhibition of exopolysaccharides (EPS) secretion supported the biofilms data and deciphered a possible mode of action. Therefore, such green synthesized nanoparticles can be used as an alternative in management of MDR infection at least for tropical application after careful in vivo validation.

Copper compounds are promising candidates for next-generation metal anticancer drugs. Therefore, we synthesized and characterized a formate bridged 1D coordination polymer [Cu(L)(HCOO)2]n, (L = 2-methoxy-6-methyl-3-((quinolin-8-ylimino)methyl)chroman-4-ol), PCU1, wherein the Cu(ii) center adopts a square pyramidal coordination environment with adjacent CuCu distances of 5.28 A. Primarily, in vitro DNA interaction studies revealed a metallopolymer which possesses high DNA binding propensity and cleaves DNA via the oxidative pathway. We further analysed its potential on cancerous cells MCF-7, HeLa, A549, and two non-tumorigenic cells HEK293 and HBE. The selective cytotoxicity potential of PCU1 against A549 cells driven us to examine the mechanistic pathways comprehensively by carrying out various assays viz, cell cycle arrest, Annexin V-FTIC/PI assay, autophagy, intercellular localization, mitochondrial membrane potential 'MMP', antiproliferative assay, and gene expression of TGF-β and MMP-2.

Biocompatible tryptophan-derived copper (1) and zinc (2) complexes with norharmane (β-carboline) were designed, synthesized, characterized, and evaluated for the potential anticancer activity in vitro and in vivo. The in vitro cytotoxicity of both complexes 1 and 2 were assessed against two cancerous cells: (human breast cancer) MCF7 and (liver hepatocellular cancer) HepG2 cells with a non-tumorigenic: (human embryonic kidney) HEK293 cells. The results exhibited a potentially decent selectivity of 1 against MCF7 cells with an IC50 value of 7.8 ± 0.4 μM compared to 2 (less active, IC50 ~ 20 μM). Furthermore, we analyzed the level of glutathione, lipid peroxidation, and visualized ROS generation to get an insight into the mechanistic pathway and witnessed oxidative stress. These in vitro results were ascertained by in vivo experiments, which also supported the free radical-mediated oxidative stress. The comet assay confirmed the oxidative stress that leads to DNA damage. The histopathology of the liver also ascertained the low toxicity of 1.

Aerogels are a unique class of materials that possess intriguing properties such as very light weight, low bulk density, high porosity, heat resistance, very high specific surface area, low dielectric constant, and low refractive index. Synthetic polymer-based aerogels have poor biodegradability, toxic precursors along with hazardous degradation products make them inadequate for use. Focus has shifted to the fabrication of aerogels from biological materials. Polysaccharides, proteins, polymers derived from biomass have been exploited to produce bio-aerogels. The biological synthesis of aerogels is advantageous because these materials are biodegradable, biocompatible, abundant in nature, and involve no toxic materials making them candidate of choice for various biomedical and environmental applications. Therefore, this article attempts to review the different types of bio-inspired aerogel materials, there synthesis and environmental applications.

Statistics show that more than 700 thousand tons of dye are produced annually across the globe. Around 10&ndash, 20% of this is used in industrial processes such as printing and dyeing, while about 50% of the dye produced is discharged into the environment without proper physicochemical treatment. Even trace amounts of dye in water can reduce oxygen solubility and have carcinogenic, mutagenic, and toxic effects on aquatic organisms. Therefore, before dye-containing wastewater is discharged into the environment, it must be properly treated. The present study investigates the green synthesis of nickel ferrite NiFe2O4 (NIFE) spinel magnetic nanoparticles (MNPs) via chemical coprecipitation of a solution of Ni2+/Fe3+ in the presence of a biopolymer blend of chitosan (CT) and ascorbic acid (AS). The magnetic nanomaterial was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy&ndash, energy dispersive X-ray analysis (SEM-EDX), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-Vis), differential scanning calorimetry (DSC), and vibrating-sample magnetometry (VSM). The material was further explored as a catalyst for the photocatalytic degradation of malachite green (MG) under visible light irradiation coupled with ultrasonic waves. The combination of 90 min of visible solar light irradiation with 6.35 W&middot, mL&minus, 1 ultrasonic power at pH 8 resulted in 99% of the photocatalytic efficiency of chitosan-ascorbic acid@NIFE (CTAS@NIFE) catalyst for 70 mg&middot, L&ndash, 1 MG. The quenching of the photocatalytic efficiency from 98% to 64% in the presence of isopropyl alcohol (IPA) suggested the involvement of hydroxy (&bull, OH) radicals in the mineralization process of MG. The high regression coefficients (R2) of 0.99 for 35, 55, and 70 mg&middot, L&minus, 1 MG indicated the sonophotocatalysis of MG by CTAS@NIFE was best defined by a pseudo first-order kinetic model. The mechanism involves the adsorption of MG on the catalyst surface in the first step and thereby mineralization of the MG by the generated hydroxyl radicals (&bull, OH) under the influence of visible radiation coupled with 6.34 W&middot, mL&ndash, 1 ultrasonic power. In the present study the application of photodegradation process with sonochemistry results in 99% of MG mineralization without effecting the material structure unlike happens in the case adsorption process. So, the secondary pollution (generally happens in case of adsorption) can be avoided by reusing the spent material for another application instead of disposing it. Thus, the ecofriendly synthesis protocol, ease in design of experimentation like use of solar irradiation instead of electric power lamps, reusability and high efficiency of the material suggested the study to be potentially economical for industrial development at pilot scale towards wastewater remediation.

Herein, we report PAN-g-Alg@Ag-based nanocatalysts synthesis via in situ oxidative free-radical polymerization of acrylonitrile (AN) using Alg@Ag nanoparticles (Alg@Ag NPs). Various analytical techniques, including FTIR, XRD, SEM, TEM, UV&ndash, Vis, and DSC, were employed to determine bonding interactions and chemical characteristics of the nanocatalyst. The optimized response surface methodology coupled central composite design (RSM&ndash, CCD) reaction conditions were a 35-min irradiation time in a 70-mg L&minus, 1 2,4-dinitrophenol (DNP) solution at pH of 4.68. Here, DNP degradation was 99.46% at a desirability of 1.00. The pseudo-first-order rate constant (K1) values were 0.047, 0.050, 0.054, 0.056, 0.059, and 0.064 min&minus, 1 with associated half-life (t1/2) values of 14.74, 13.86, 12.84, 12.38, 11.74, 10.82, and 10.04 min that corresponded to DNP concentrations of 10, 20, 30, 40, 50, 60, and 70 mg L&minus, 1, respectively, in the presence of PAN-g-Alg@Ag (0.03 g). The results indicate that the reaction followed the pseudo-first-order kinetic model with an R2 value of 0.99. The combined absorption properties of PAN and Alg@Ag NPs on copolymerization on the surface contributed more charge density to surface plasmon resonance (SPR) in a way to degrade more and more molecules of DNP together with preventing the recombination of electron and hole pairs within the photocatalytic process.

In the present study, mesoporous silica nanoparticles (MSNs) synthesized through sol&ndash, gel process and calcined at 600 &deg, C were further surface functionalized by a copolymer chain of L-ascorbic acid (AS) and polyaniline (PAni) by in situ free radical oxidative polymerization reaction. The surface modification of MSNs by AS-g-PAni was confirmed by using various analytical techniques, namely FTIR, XRD, SEM&ndash, EDX, TEM and AFM. The composition of AS-g-PAni@MS was found to be composed of C (52.53%), N (20.30%), O (25.69%) and Si (1.49%), with 26.42 nm as the particle size. Further, it was applied for the adsorption of crystal violet (CV) dye under batch, as well as fixed bed method. RSM&ndash, BBD was taken into consideration, to optimize the various operational parameters effecting the adsorption through batch method. To explore maximum efficiency of the material, it was further subjected to adsorption of CV under fixed bed method, using the variable bed heights of 3.7, 5.4 and 8.1 cm. Based on high value of regression coefficient (R2) and low value of RMSE given as (0.99, 0.02) for 3.7 cm, (0.99, 0.03), the breakthrough data were very well defined by the Thomas model, with optimum concurrence of stoichiometric adsorption capacity values. The external mass transfer equilibrium data were well fitted by the Langmuir model, with maximum monolayer adsorption capacity of 88.42 mg g&minus, 1 at 303K, 92.51 mg g&minus, 1 at 313 K, 107.41 mg g&minus, 1 at 313 K and 113.25 mg g&minus, 1 at 333 K. The uptake of CV by AS-g-PAni@MS was well defined by pseudo second order model with rate constant K2 = 0.003 L mg&ndash, 1 min&ndash, 1 for 50 and 0.003 L mg&ndash, 1 for 60 mg L&ndash, 1 CV. The adsorption reaction was endothermic with enthalpy (&Delta, H) value of 3.62 KJ mol&minus, 1 and highly efficient for treatment of CV-contaminated water for more the five consecutive cycles.

We report the facile hydrothermal synthesis of polyaniline (PANI)-modified molybdenum disulfide (MoS2) nanosheets to fabricate a novel organic&ndash, inorganic hybrid material. The prepared 3D nanomaterial was characterized by field emission scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction studies. The results indicate the successful synthesis of PANI&ndash, MoS2 hybrid material. The PANI&ndash, MoS2 was used to study the extraction and preconcentration of trace mercury ions. The experimental conditions were optimized systematically, and the data shows a good Hg(II) adsorption capacity of 240.0 mg g&minus, 1 of material. The adsorption of Hg(II) on PANI&ndash, MoS2 hybrid material may be attributed to the selective complexation between the&ndash, S ion of PANI&ndash, MoS2 with Hg(II). The proposed method shows a high preconcentration limit of 0.31 &micro, g L&minus, 1 with a preconcentration factor of 640. The lowest trace Hg(II) concentration, which was quantitatively analyzed by the proposed method, was 0.03 &micro, 1. The standard reference material was analyzed to determine the concentration of Hg(II) to validate the proposed methodology. Good agreement between the certified and observed values indicates the applicability of the developed method for Hg(II) analysis in real samples. The study suggests that the PANI&ndash, MoS2 hybrid material can be used for trace Hg(II) analyses for environmental water monitoring.

Advanced glycation endproducts (AGEs) are the final product of glycation, highly reactive in nature and contribute directly or indirectly to numerous complications related to diabetes. In this study, the antiglycation activity of glyburide was investigated using HSA as model protein, both against glucose and methylglyoxal mediated glycation. The possible mechanism of action was also deciphered using biophysical and computational tools. Approximately 70% inhibition of both early and advanced glycation end products were recorded in the presence of glyburide. Free lysine modification was reduced by glyburide treatment and improvement in biochemical markers such as free thiol groups and carbonyl content was observed. Interaction studies revealed that glyburide showed moderate to strong binding affinity towards HSA with binding constant in the order of 106 M−1. The interaction of glyburide with HSA was entropically favourable and spontaneous in nature. Molecular dynamics simulation deciphered that glyburide-HSA complex was quite stable where RMSD, RMSF, Rg, SASA, and secondary structure of HSA remained approximately same over the entire simulation period. The average binding energy of the MD simulation for glyburide-HSA complex was found to be −15.386 kJ mol−1. The findings demonstrate the antiglycation potential of glyburide and its possible mechanism of action.

Foodborne pathogens are one of the major cause of food-related diseases and food poisoning. Bacterial biofilms and quorum sensing (QS) mechanism of cell–cell communication have also been found to be associated with several outbreaks of foodborne diseases and are great threat to food safety. Therefore, In the present study, we investigated the activity of three tetrahedrally coordinated copper(I) complexes against quorum sensing and biofilms of foodborne bacteria. All the three complexes demonstrated similar antimicrobial properties against the selected pathogens. Concentration below the MIC i.e. at sub-MICs all the three complexes interfered significantly with the quorum sensing regulated functions in C. violaceum (violacein), P. aeruginosa (elastase, pyocyanin and alginate production) and S. marcescens (prodigiosin). The complexes demonstrated potent broad-spectrum biofilm inhibition in Pseudomonas aeruginosa, E. coli, Chromobacterium violaceum, Serratia marcescens, Klebsiella pneumoniae and Listeria monocytogenes. Biofilm inhibition was visualized using SEM and CLSM images. Action of the copper(I) complexes on two key QS regulated functions contributing to biofilm formation i.e. EPS production and swarming motility was also studied and statistically significant reduction was recorded. These results could form the basis for development of safe anti-QS and anti-biofilm agents that can be utilized in the food industry as well as healthcare sector to prevent food-associated diseases. Keywords: Copper compounds, Biofilm, Quorum sensing, Food safety, Pathogens

The development of preferentially selective cancer chemotherapeutics is a new trend in drug research. Thus, we designed and synthesized novel ternary complexes, [Cu(tryp)(Hnor)2(DMSO)]NO3 (1) and [Zn(tryp)(Hnor)2(DMSO)]NO3 (2) (tryp = DL-Tryptophane; Hnor = Norharmane, β-carboline; DMSO = Dimethyl sulfoxide), characterized with elemental analysis, FTIR, UV–vis, FL, NMR, ESI-MS, and molar conductivity. Furthermore, the TD-DFT studies with UV–vis and FTIR validated the proposed structures of 1 and 2. Moreover, we evaluated the HOMO-LUMO energy gap and found that 1 has a smaller energy gap than 2. Then, 1 and 2 were assessed for anticancer chemotherapeutic potential against cancer cell lines MCF7 (human breast cancer) and HepG2 (human liver hepatocellular carcinoma) as well as the non-tumorigenic HEK293 (human embryonic kidney) cells. The MTT assay illustrated the preferentially cytotoxic behavior of 1 when compared with that of 2 and cisplatin (standard drug) against MCF7 cells. Moreover, 1 was exposed to MCF7 cells, and the results indicated the arrest of the G2/M phases, which followed the apoptotic pathway predominantly. Generation of ROS, GSH depletion, and elevation in LPO validated the redox changes prompted by 1. These studies establish the great potential of 1 as a candidate for anticancer therapeutics.

Using a rare-earth metal-based catalytic system, methyl oleate has been transformed into corresponding keto-derivatives via a Meinwald rearrangement of epoxidized methyl oleate (EMO). YCl3 efficiently carried out ring-opening of EMO under solvent-free conditions within a short reaction time. Only 3 wt% of YCl3 is enough to deliver selectively keto-products in excellent yields without requiring any column purifications. Also, this catalytic approach is very effective with a representative set of biobased unsaturated fatty acid methyl esters (FAME). Overall, this effective synthesis of keto-derivatives promises novel materials with high biobased content and is very useful for industries of today and the future.

Herein, we report the synthesis and structural investigation of CuII-NaI heterobimetallic complex 1, which comprises of the compartmental Schiff-base ligand (H2L) derived from DACH (1,2-Diaminocyclohexane) and o-vanillin. B3LYP/TZVP DFT calculation was performed to get a deeper insight of the ground state electronic structure, and quantitative analysis of non-covalent interactions was carried out using Hirshfeld surface analysis to explore H-bonding, C-H···π, Cu···C-H and Cu···H-C interactions. Furthermore, in vitro DNA binding studies with Complex 1 demonstrated the electrostatic mode of interaction at the major groove of the DNA. Complex 1 showed the oxidative damage of pBR322 DNA via ROS generation. Additionally, in vitro cytotoxicity and genotoxicity of complex 1 were investigated on human breast cancer cells (MCF-7), revealed concentration-dependent cell viability at micromolar concentration level. Flow cytometric analysis confirmed the cytotoxic potential of complex 1 as the percentage of apoptotic cells were increased in the treatment group. Genotoxicity was evident in the induction of micronucleus and DNA fragmentation.

Two new homometallic Cu4O4 cubane clusters 1 and 2 have been synthesized by self-assembly of copper(II) acetate and ligand, 2-[(2-Hydroxy-3-methoxy-benzylidene)-amino]-2-hydroxymethyl-propane-1,3-diol (H4L) and characterized thoroughly by various spectroscopic techniques and single crystal X-ray diffraction analysis. Temperature-dependent magnetic susceptibility measurements have been performed to elucidate the antiferromagnetic and ferromagnetic nature in Cu4O4 clusters 1 and 2, respectively. In vitro DNA binding studies of cubane clusters were carried out by employing optical spectroscopic techniques. Gel electrophoretic mobility assay performed to examine the nuclease activity of the complexes 1 and 2 with pBR322 DNA, and results revealed oxidative DNA cleavage via reactive oxygen species (ROS) species viz., O2 ‾, 1O2, etc. In vitro cell proliferation via MTT assay was studied to calculate the cytotoxicity of complexes 1 and 2. The IC50 evaluated were ∼20 µM in MCF-7 (Breast) and ∼30–35 µM in HepG2 (Liver) cancer cell lines. Additionally, in the presence of 1 and 2, ROS and TBARS (Thiobarbituric acid reactive substance) levels amplified significantly, coupled with GSH (glutathione) levels in cancer lines. Hence, the results exhibited the major role of ROS in apoptosis induced by 1 and 2 clusters and validate their prospective to be efficient anticancer drug entities.

Speciation and accurate determination of class I carcinogen As(III) species from complex samples remains challenging either due to lack of selectivity and/or ultra-low analyte concentration or matrix interference. Sample preparation via preconcentration increases the analyte concentration far above the instrumental detection limit, and simultaneously clean up the sample for accurate analysis. Herein, we report a new nano-sorbent consisting of a magnetite Fe3O4 core coated with β-lactoglobulin (β-lg) shell. The prepared Fe3O4@β-lg sorbent are of uniform size with an average diameter of 1 µm. The Fe3O4@β-lg nanocomposite selectively binds As(III) over As(V) ions at wider pH range. Experiments were conducted to optimize the sample pH, column flow rate, preconcentration factor and suitable eluent to recover the sorbed analyte ions. The technique was effectively used to evaluate the As(III) species in ecological water samples. The detection limits (3σ/m) of the proposed method was found to be 0.98 ng L−1. The recovery of the spiked amount following the optimized procedure was ranges from 97.0 to 100%.

Sunset yellow is synthetic azo dye used to color food products in food industry. Sunset yellow has no toxicity if taken in permissible amounts. The daily acceptable intake of dye is 2.5 mg/Kg as per WHO health guidelines. Above the permissible limit, sunset yellow dye is dangerous posing serious threat to human health worldwide leading to multiorgan (gastric, immunological, neurological) failure related symptoms especially in children can cause DNA damage. Other symptoms include ADHD like behavior in children. This has led to Food Safety Agencies to regulate permissible limit of sunset yellow in food products. Therefore, it is necessary to develop method for the removal of dye in different foodstuffs. Nano-sized fluorescent carbon dots (CDs) have been synthesized from spices (fenugreek, cloves and cumin) under hydrothermal conditions. Characterization has been done through UV–Vis, TEM, FT-IR and XRD spectroscopy. Results reveals that CDs possess high water solubility due to surface rich hydroxyl groups, excellent photo-stability and are non-toxic. There was strong quenching of fluorescence intensity (F0/F) of CDs in the presence of sunset yellow food dye. Further, there was no effect to fluorescence intensity with the presence of interferences. The linear concentration range obtained was 0.25 µM-60.0 µM with the detection limit of 0.20 µM. The calculated relative standard deviation (RSD) for determination of sunset yellow was found to be 0.21%. The present method was applied successfully for the determination of sunset yellow dye in various food samples with recovery values of 99.8 and 103.6%.

New open–cubane tetranuclear copper(II) complex of formulation {[Cu4(HL)4(H2O)2]·(CH3OH)2·(H2O)5}(1) derived from Schiff base ligand 2–((E)–(1,3–dihydroxy–2–methylpropan–2–ylimino)methyl)–6–methoxyphenol (HL) was synthesized. The characterization of both ligand (HL) and tetranuclear Cu complex was carried out by analytical, spectroscopic and single crystal X–ray diffraction. The structure analyses revealed that in the tetranuclear core, the metal centers are mutually interconnected via two phenoxo oxygen and two alkoxo oxygen atoms of four H2L2− ligand to generate a distorted single–open [Cu4(μ3–O)2]6+ open cubane core with the four Cu atoms disposed in an extended “butterfly–like” arrangement. Binding of complex 1 with CT DNA was investigated by using vivid spectroscopic techniques to study the mode of the interaction of 1 towards CT DNA. The results obtained indicated that 1 avidly binds to CT DNA via electrostatic mode with an intrinsic binding constant, Kb value 4.63 × 104 M–1. Complex 1 showed an impressive nuclease activity generating single–strand breaks and the mechanistic investigation confirms the contribution of the reactive oxygen species (ROS). Likewise, the interaction of 1 with human serum album (HSA) revealed the change in intrinsic fluorescence intensity of HSA and was supposed to be associated with the microenvironment of Trp residue. Furthermore, the interaction of complex 1 with DNA and HSA was further investigated by the molecular docking studies which corroborated well with above findings. We have also tested 1 for cytotoxicity against the PC3 (Prostate) and K562 (Leukemia) cancer cell lines. The results exhibited were moderate when compared to standard drug viz, adriamycin (ADR).

Seeking to enrich the yet less explored field of scorpionate complexes bearing antioxidant properties, we, here, report on the synthesis, characterization and assessment of the antioxidant activity of new complexes derived from three scorpionate ligands. The interaction between the scorpionate ligands thallium(I) hydrotris(5-methyl-indazolyl)borate (TlTp4Bo,5Me), thallium(I) hydrotris(4,5-dihydro-2H-benzo[g]indazolyl)borate (TlTpa) and potassium hydrotris(3-tert-butyl- pyrazolyl)borate (KTptBu), and metal(II) chlorides, in dichloromethane at room temperature, produced a new family of complexes having the stoichiometric formula [M(Tp4Bo,5Me)2] (M = Cu, 1, Zn, 4, Cd, 7), [M(Tpa)2] (M = Cu, 2, Zn, 5, Cd, 8), [Cu(HpztBu)3Cl2] (3), [Zn(TptBu)Cl] (6) and [Cd(BptBu)(HpztBu)Cl] (9). The obtained metal complexes were characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance and elemental analysis, highlighting the total and partial hydrolysis of the scorpionate ligand TptBu during the synthesis of the Cu(II) complex 3 and the Cd(II) complex 9, respectively. An assessment of the antioxidant activity of the obtained metal complexes was performed through both enzymatic and non-enzymatic assays against 1,1-diphenyl-2-picryl- hydrazyl (DPPH&middot, ), 2,2&prime, Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+&middot, ), hydroxyl (HO&middot, ), nitric oxide (NO&middot, ), superoxide (O2&minus, ) and peroxide (OOH&middot, ) radicals. In particular, the complex [Cu(Tpa)2]&sdot, 0.5H2O (2) exhibited significant antioxidant activity, as good and specific activity against superoxide (O2&minus, &middot, ), (IC50 values equal to 5.6 &plusmn, 0.2 &mu, M) and might be identified as auspicious SOD-mimics (SOD = superoxide dismutase).

The designing of metal-based anticancer therapeutic agents can be optimized in a better and rapid way if the ligands utilized have standalone properties. Therefore, even when the organometallic/coordination complex (i.e., metallodrug) gets dissociated in extreme conditions, the ligand can endorse its biological properties. Herein, we have synthesized and characterized ɳ6-p-cymene ruthenium diclofenac complex. Furthermore, the ruthenium complex interactions with human serum albumin (HSA) and ct-DNA have been studied using various spectroscopic studies viz., UV, fluorescence, and circular dichroism and exhibited a significant binding propensity. Furthermore, in vitro cytotoxicity assays were carried out against human breast cancer “MCF-7” cell line. The ɳ6-p-cymene ruthenium diclofenac complex registered significant cytotoxicity with an IC50 value of ∼25.0 µM which is comparable to the standard drugs. The ɳ6-p-cymene ruthenium diclofenac complex was able to decrease the MCF-7 cell proliferation and induced significant levels of apoptosis with relatively low toxicity.

A novel coumarin based Schiff base sensor probe 1, was synthesized and structural elucidation was carried out by FTIR, UV–vis, 1H and 13C NMR and MS spectroscopy. The optical properties of the sensor probe were investigated by employing absorption and fluorescence titrations which showed specific recognition behaviour being highly selective towards Cd2+ over the other 3d transition metal ions. The strong fluorometric response of probe 1 towards Cd2+ ion is attributed to inhibition of C=N isomerization effect upon coordination of the metal ion. The binding stoichiometry was determined by Job’s plot and the probable sensing mechanism of the probe towards Cd2+ was investigated by employing FTIR spectra analysis and 1H NMR titration experiments. Computational validation of the sensing mechanism in various modes towards Cd2+ was also performed by carrying out the DFT studies which were found to be in good concordance with the experimental results. The reversible nature of the probe was studied by EDTA titration indicating that it can be reused. Interaction studies of the sensor probe with the BSA showed the practical applicability for the quantitative determination of Cd2+ concentration in the blood plasma. The lower detection limit of the probe upto 0.114 μM further proves its practical application in the sensing phenomenon.

Binuclear copper(II) cocrystal “[Cu2(valdien)2⋯2Cl2CHCOOH],” 1 was synthesized from H2valdien scaffold and anticancer drug pharmacophore “dichloroacetic acid” embedded with two Cu(II) connected via a hydrogen bonded network. [Cu2(valdien)2⋯2Cl2CHCOOH] 1 was thoroughly characterized by single-crystal XRD and by other spectroscopic techniques. The non-covalent interaction (NCI) index and Hirshfeld surface analysis were used to study the various kinds of interactions (O⋯H, N⋯H, H⋯Cl, Cu⋯H, C⋯O, N⋯O, C⋯Cl, and O⋯Cl, etc.) responsible for the stabilization of crystal lattice. [Cu2(valdien)2⋯2Cl2CHCOOH] 1 was validated as potential antitumor drug entity by studying its DNA binding profile, cleavage mechanism with pBR322 by gel electrophoretic assay and in vitro cytotoxicity on MCF-7 cancer cell lines. The mechanistic pathways were also deduced via dual staining AO/EB of cancer cells which confirmed the potential of the cocrystal [Cu2(valdien)2⋯2Cl2CHCOOH] 1 to act as effective anticancer agent towards breast cancers.

Coumarins are well known for the design of target-specific therapeutics for cancer oncology. In lieu of their potential applications as antitumor chemotherapeutics, a new coumarin-based copper(II) complex 1 was synthesized employing 6-methyl-3-((quinolin-8-ylimino)methyl)-3H-chromene-2,4-dione (L). The structure elucidation of 1 was done by various spectroscopic techniques (viz., IR, Raman, UV-vis, and EPR), elemental analysis and single crystal X-ray diffraction. Raman and IR combined with B3LYP/DFT frequency calculations were used to characterize the lattice dynamics with an emphasis on the doming mode vibrations of the copper site. Prominent features in the Raman and far-IR spectrum, indicative of doming modes, appeared in the 35–150 cm−1, other out-of-plane and in-plane mode of vibrations in the range of 160–250 cm−1 and 260–700 cm−1, respectively. Furthermore, preliminary in vitro binding studies of L and complex 1 with CT-DNA were carried out by various biophysical techniques. The results demonstrated that 1 avidly binds to CT DNA as compared to L and cisplatin (marketed drug in use for treating solid cancers) via a partial intercalative mode. Furthermore, pBR322 cleavage studies of 1 revealed the hydrolytically double-stranded cleavage pattern verified by T4 ligase religation. The cytotoxicity activity of L and complex 1 was carried out to evaluate cell growth inhibition in a human alveolar epithelial A549 cancer cells (human lung carcinoma) by the MTT assay. Interestingly, the IC50 value of complex 1 was found to be 4.6 ± 0.3 μM which is significantly lower as compared to the IC50 values of previously reported Cu(II) complexes. Furthermore, in the presence of 1, the level of reactive oxygen species (ROS) and thiobarbituric acid reactive substance (TBARS) displayed significant increase, coupled with reduced glutathione (GSH) levels on the A549 cancer cell. Thus, the results confirm the important role of ROS generation and discover Cu(II) complex 1 induced cell apoptosis and validate its potential to act as a robust anticancer drug entity.

New organoruthenium [(η 6 -arene)Ru II (L)Cl]Cl ( 1 : arene = p -cymene, L = L 1 ; 2 : arene = p -cymene, L = L 2 ; 3 : arene = benzene, L = L 1 ; 4 : arene = benzene; L = L 2 ; L 1 = bis(3,5-dimethylpyrazolyl)parabenzoic acid, L 2 = bis(3,5-dimethylpyrazolyl)metabenzoic acid) have been synthesized and characterized by analytical and spectroscopic methods. The molecular structure of [(η 6 - p -cymene)RuCl(L 1 )]Cl ( 1 ) was determined by single crystal X-ray diffraction studies. Preliminary in vitro binding studies of 1 – 4 with CT DNA were carried out by employing various biophysical techniques which revealed their avid DNA binding via non-covalent binding mode viz; partial intercalation of the η 6 -arene group as well as electrostatic surface interaction through one oxygen atom of the phosphate backbone of the DNA helix; however, complexes 1 and 3 display higher binding propensity in comparison to 2 and 4 , as quantified by K b . The interaction was further analysed by HPLC technique. The results of the cleavage experiments of pBR322 DNA with 1 and 3 displayed significantly good cleavage at 20–40 μM, following the oxidative pathway. These findings have revealed that the hydrophobic arene, and the chloride leaving group have important roles in the novel mechanism of recognition of DNA by (η 6 -arene)ruthenium(II) complexes, and will aid the design of more effective anticancer complexes, as well as new site-specific DNA reagents. Furthermore, the anticancer activity of the complexes 1 and 3 on 15 cell lines of different histological origin has been studied. It has been observed that 1 exhibits higher cytotoxicity than 3 , and the cells undergo apoptotic cell death.

A diaminobenzophenone Schiff base derived probe 1, was synthesized and structure elucidation was carried out by spectroscopic studies viz., FT–IR, UV–vis, 1H, and 13C NMR and mass spectrometry. The sensing phenomenon with different metal ions (Cr3+, Mn2+, Fe2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+) was investigated by employing absorption and fluorescence titrations, which demonstrated that probe 1 exhibited selective fluorescent sensing behavior towards Fe2+ ion among various other metal ions. The porobes selceteclivity towards Fe2+ was also examined by colorimetric assay which revealed a change in the color from light yellow to brown upon addition of Fe2+ ion. A remarkable increase in the fluorescence intensity of probe 1 was observed towards Fe2+ ion, which was found to be associated with the inhibition of photoinduced electron–transfer (PET) and C N isomerization processes, respectively. The chemosensor exhibited an association constant value of 6.173 × 107 M−2 as determined by using non–linear least square fit data. Job’s plot calculated the binding stoichiometry, and the sensing phenomenon of Fe2+ towards the probe was further supported by Density Functional Theory (DFT) calculations and 1H NMR studies. The detection limit of probe 1 was found to be 0.0363 µM, which is below the permissible limits according to the WHO guideline (5 μM) for Fe2+ ions in the drinking water. Furthermore, the practical application of probe 1 was studied by analyzing the content of Fe2+ in different water samples.

Epoxy resins (EP) have been used as a thermos-setting material in the field of coating, casting, bonding agent, and laminating. However, a major drawback associated with its use is the lack of good flaming properties, and it is responsible for heavy smoke along with hazardous gases considerably limiting its uses in various fields. In this study, N-ethanolamine triazine-piperizine, a melamine polymer (ETPMP), was established as a new charring-foaming agent and was successfully synthesized with ethanolamine, piperizine, cyanuric chloride, and melamine as precursor molecules via the nucleophilic substitution reaction method. Elemental analysis and Fourier transform infrared (FTIR) spectroscopy analysis were applied to approve the synthesis of ETPMP and confirmation of its structure and characterization. The epoxy coating of intumescent flame retardant (IFR) was equipped by introducing ETPMP, ammonium polyphosphate (APP), and copper oxide (CuO) in multiple composition ratios. CuO was loaded at various amounts into the IFR-coating system as a synergistic agent. The synergistic action of CuO on IFR coatings was scientifically examined by using different analytical tests such as vertical burning test (UL-94V), limited oxygen index (LOI), thermal gravimetric analysis (TGA), cone calorimeter, and scanning electron microscope (SEM). The results showed that small changes in the amount of CuO expressively amplified the LOI results and enhanced the V-0 ratings in the UL-94V test. The TGA data clearly demonstrate that the inclusion of CuO can transform the thermal deprivation behavior of coatings with a growing char slag proportion with elevated temperatures. Information from cone calorimeter data affirmed that CuO can decrease the burning factors by total heat release (THR) together with peak heat release rate (PHRR). The SEM images indicated that CuO can enrich the power and compression of the intumescent char that restricts the movement of heat and oxygen. Our results demonstrate a positive influence of CuO on the epoxy-headed intumescent flame retardant coatings.

Ethylenediamine modified Ammonium polyphosphate (EDA-MAPP), and Charring-Foaming Agents (CFA) was prepared via a simple chemical approach and further utilizes for the preparation of Epoxy resin based intumescent flame retardation coatings. The ratio belongs to MAPP and CFA was fixed at 2:1 ratio. Comparative thermo gravimetric analysis TGA study of Modified Ammonium polyphosphate (MAPP) and Ammonium polyphosphate (APP) investigated. Sb2O3 was introduced into flame retardation coating formulation at various amounts to evaluate the synergistic action of Sb2O3 along with flame retardant coating system. The synergistic action of Sb2O3 on flame retardation coating formulation was studied by vertical burning test (UL-94V), thermo gravimetric analysis (TGA), Limited Oxygen Index (LOI), and Fourier Transform Infra-Red spectroscopy (FTIR). The UL-94V results indicated that adding Sb2O3 effectively increased flame retardancy and meets V-0 ratings at each concentration. The TGA results revealed that the amalgamation of Sb2O3 at each concentration effectively increased the thermal stability of the flame retardant coating system. Cone-calorimeter study results that Sb2O3 successfully minimized the combustion parameters like, Peak Heat Release Rate (PHRR), and Total Heat Release (THR). The FTIR result shows that Sb2O3 can react with MAPP and generates the dense-charred layer which prevents the transfer of heat and oxygen.

Water pollution caused by metal contamination is of serious concern. Direct determination of trace metal ions in real water samples remains challenging. A sample preparation technique is a prerequisite before analysis. Herein, we report the facile water-based hydrothermal synthesis of cadmium sulfide nanoparticles on a cellulose nanofiber surface to prepare a new adsorbent material. Field emission scanning electron microscopy, high-resolution tunneling electron microscopy, elemental mapping and X-ray photoelectron microscopy were used to characterize the surface morphology, structural determination, elemental composition and nature of bonding. The nanoadsorbent (cadmium-sulfide-decorated cellulose nanofibrils (CNFs@CdS)) was employed for the solid-phase extraction and determination of trace Hg(II) from aqueous media. The experimental conditions were optimized systematically and the data show a good Hg(II) adsorption capacity of 126.0 mg g&minus, 1. The CNFs@CdS adsorbent shows the selective removal of Hg(II) accordingly to the hard and soft acid&ndash, base theory of metal&ndash, ligand interaction. A high preconcentration limit of 0.36 &micro, g L&minus, 1 was obtained with a preconcentration factor of 580. The lowest level of trace Hg(II) concentration, which was quantitatively analyzed by the proposed method, was found to be 0.06 &micro, 1. No significant interferences from the sample matrix were observed in the extraction of Hg(II). Analysis of the standard reference material (SRM 1641d) was carried out to validate the proposed methodology. Good agreement between the certified and observed values indicates the applicability of the developed methodology for the analysis of Hg(II) in tap water, river water and industrial wastewater samples.

Here we report a material β-CD/PANI/MWCNTs prepared through oxidative free radical polymerization of aniline (C6H5NH2) monomer in the presence of β-CD and MWCNTs. Indigenous analytical techniques like SEM, TEM, XRD, XPS, UV–vis, and FTIR were analyzed for the characterization of the material. The principle utility of the material was extrapolated towards the visible light-mediated photodegradation of crystal violet (CV) dye. The optimized values of process variables like radiation time 120 min, pH of the dye solution as pH 5, photocatalyst dose as 15 mg, and the concentration of CV as 135 mg L−1 were taken form RSM-CCD model at 298 K temperature. The desirability of the experiment was found to be D = 0.95 with qe, exp = 179.25 mg g−1 (93.54%) and qe, cal = 184.76 mg g−1 (95.39%) of CV degradation. The bandgap energy (Eg) of the material using Tauc's plot was found to be 3.2 eV. Benzoic acid (BA) as a trapping agent decreases the photodegradation capacity drastically suggesting the major role of •OH− radical as reactive oxidant (RO) for the CV degradation. The rate-determining step, as suggested by the pseudo-first-order model in heterogeneous catalysis, follows the adsorption of CV molecule on β-CD/PANI/MWCNTs surface and thereby their dissipation through reactive OH• radicals. The values of first-order rate constants (K1) having values of 0.014, 0.015, 0.016, 0.018 and 0.019 min−1 and a t1/2 values of 49.5, 46.2, 43.3, 38.5 and 36.5 min were calculated for 30, 60, 90, 120 and 135 mg L−1 of CV with 15 mg of photocatalyst.

Antimicrobial resistance among pathogenic bacteria has become a global threat to human health. Due to poor progress in development of new antimicrobial drugs, there is a need for the development of novel alternative strategies to combat the problem of multidrug resistance. Moreover, there is focus on ecofriendly approach for the synthesis nanoparticles having efficient medicinal properties including antivirulence properties to tackle the emergence of multi-drug resistance. Targeting quorum sensing controlled virulence factors and biofilms has come out to be a novel anti-infective drug target. The silver nanoparticles (Ag@CC-NPs) were synthesized from aqueous extract of Carum copticum and characterized using UV-vis absorption spectroscopy, fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Ag@CC-NPs were checked for its ability to inhibit quorum sensing-mediated virulence factors and biofilms against three test pathogens at sub-MIC values. There was ~75% inhibition of violacein production by Ag@CC-NPs against C. violaceum. The P. aeruginosa virulence factors such as pyocyanin production, pyoverdin production, exoprotease activity, elastase activity, swimming motility and rhamnolipid production were inhibited by 76.9, 49.0, 71.1, 53.3, 89.5, and 60.0% at sub-MIC. Moreover, virulence factors of S. marcescens viz. prodigiosin production, exoprotease activity, and swarming motility was reduced by 78.4, 67.8, and 90.7%. Ag@CC-NPs also exhibited broad-spectrum antibiofilm activity with 77.6, 86.3, and 75.1% inhibition of biofilms of P. aeruginosa, S. marcescens, and C. violaceum respectively. The biofilm formation on glass coverslip was reduced remarkably as evident from SEM and CLSM analysis. The findings revealed the in vitro efficacy of Ag@CC-NPs against bacterial pathogens and can be exploited in the development of alternative therapeutic agent in management of bacterial infections for topical application, mainly wound infection, or coating of surfaces to prevent bacterial adherence on medical devices.

Cancer and the associated secondary bacterial infections are leading cause of mortality, due to the paucity of effective drugs. Here, we have synthesized silver nanoparticles (AgNPs) from organic resource and confirmed their anti-cancer and anti-microbial potentials. Microwave irradiation method was employed to synthesize AgNPs using Pandanus odorifer leaf extract. Anti-cancer potential of AgNPs was evaluated by scratch assay on the monolayer of rat basophilic leukemia (RBL) cells, indicating that the synthesized AgNPs inhibit the migration of RBL cells. The synthesized AgNPs showed MIC value of 4–16 µg/mL against both Gram +ve and Gram -ve bacterial strains, exhibiting the anti-microbial potential. Biofilm inhibition was recorded at sub- MIC values against Gram +ve and Gram -ve bacterial strains. Violacein and alginate productions were reduced by 89.6 and 75.6%, respectively at 4 and 8 µg/mL of AgNPs, suggesting anti-quorum sensing activity. Exopolysaccharide production was decreased by 61–79 and 84% for Gram +ve and Gram -ve pathogens respectively. Flagellar driven swarming mobility was also reduced significantly. Furthermore, In vivo study confirmed their tolerability in mice, indicating their clinical perspective. Collective, we claim that the synthesized AgNPs have anti-metastasis as well as anti-microbial activities. Hence, this can be further tested for therapeutic options to treat cancer and secondary bacterial infections.

Development of multidrug resistance among pathogens has become a global problem for chemotherapy of bacterial infections. Extended-spectrum β-lactamase- (ESβL-) producing enteric bacteria and methicillin-resistant Staphylococcus aureus (MRSA) are the two major groups of problematic MDR bacteria that have evolved rapidly in the recent past. In this study, the aqueous extract of Murraya koenigii leaves was used for synthesis of silver nanoparticles. The synthesized MK-AgNPs were characterized using UV-vis spectroscopy, FTIR, XRD, SEM, and TEM, and their antibacterial potential was evaluated on multiple ESβL-producing enteric bacteria and MRSA. The nanoparticles were predominantly found to be spheroidal with particle size distribution in the range of 5–20 nm. There was 60.86% silver content in MK-AgNPs. Evaluation of antibacterial activity by the disc-diffusion assay revealed that MK-AgNPs effectively inhibited the growth of test pathogens with varying sized zones of inhibition. The MICs of MK-AgNPs against both MRSA and methicillin-sensitive S. aureus (MSSA) strains were 32 μg/ml, while for ESβL-producing E. coli, it ranged from 32 to 64 μg/ml. The control strain of E. coli (ECS) was relatively more sensitive with an MIC of 16 μg/ml. The MBCs were in accordance with the respective MICs. Analysis of growth kinetics revealed that the growth of all tested S. aureus strains was inhibited (∼90%) in presence of 32 μg/ml of MK-AgNPs. The sensitive strain of E. coli (ECS) showed least resistance to MK-AgNPs with >81% inhibition at 16 μg/ml. The present investigation revealed an encouraging result on in vitro efficacy of green synthesized MK-AgNPs and needed further in vivo assessment for its therapeutic efficacy against MDR bacteria.

In the present study, a facile environmentally friendly approach was described to prepare monodisperse iron oxide (Fe3O4) nanoparticles (IONPs) by low temperature solution route. The synthesized nanoparticles were characterized using x-ray diffraction spectroscopy (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM) measurements, Fourier-Transform Infrared Spectroscopy (FTIR), and Thermogravimetric analysis (TGA) analyses. XRD patterns revealed high crystalline quality of the nanoparticles. SEM micrographs showed the monodispersed IONPs with size ranging from 6 to 9 nm. Synthesized nanoparticles demonstrated MICs of 32, 64, and 128 μg/ml against Gram negative bacteria i.e., Serratia marcescens, Escherichia coli, and Pseudomonas aeruginosa, respectively, and 32 μg/ml against Gram positive bacteria Listeria monocytogenes. IOPNs at its respective sub-MICs demonstrated significant reduction of alginate and exopolysaccharide production and subsequently demonstrated broad-spectrum inhibition of biofilm ranging from 16 to 88% in the test bacteria. Biofilm reduction was also examined using SEM and Confocal Laser Scanning Microscopy (CLSM). Interaction of IONPs with bacterial cells generated ROS contributing to reduced biofilm formation. The present study for the first time report that these IONPs were effective in obliterating pre-formed biofilms. Thus, it is envisaged that these nanoparticles with broad-spectrum biofilm inhibitory property could be exploited in the food industry as well as in medical settings to curtail biofilm based infections and losses.

Potassium bromate (PB) is a commonly used food additive, a prominent water disinfection by-product, and a class IIB carcinogen. It exerts a various degree of toxicity depending on its dose and exposure duration consumed with food and water in the living organisms. The present investigation aims to demonstrate the protective efficacy of zinc oxide nanoparticles (ZnO NPs) derived from Ochradenus arabicus (OA) leaf extract by green technology in PB-challenged Swiss albino rats. The rodents were randomly distributed, under the lab-standardized treatment strategy, into the following six treatment groups: control (group I), PB alone (group II), ZnO alone (group III), ZnO NP alone (group IV), PB + ZnO (group V), and PB + ZnO NPs (group VI). The rats were sacrificed after completion of the treatment, and their blood and liver samples were collected for further analysis. Group II showed extensive toxic effects with altered liver function markers (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, gamma-glutamyl transferase, glutathione-S-transferase, and thioredoxin reductase) and compromised redox status (SOD, CAT, GR, GPx, GSH, MDA, and total carbonyl content). The histopathological analysis and comet assay further supported the biochemical results of the same group. Besides, group III also showed moderate toxicity evidenced by an alteration in most of the studied parameters while group IV demonstrated mild toxicity after biochemical analysis indicating the excellent biocompatibility of the NPs. However, group VI exhibited attenuation of the PB-induced toxic insults to a significant level as compared to group II, whereas group V failed to show similar improvement in the studied parameters. All these findings entail that the ZnO NPs prepared by green synthesis have significant ameliorative property against PB-induced toxicity in vivo. Moreover, administration of the NPs improved the overall health of the treated animals profoundly. Hence, these NPs have significant therapeutic potential against the toxic effects of PB and similar compounds in vivo, and they are suitable to be used at the clinical and industrial levels.

Herein, we have synthesized and characterized a new benzimidazole-derived “BnI” ligand and its copper(II) complex, [Cu(BnI)2], 1, and zinc(II) complex, [Zn(BnI)2], 2, using elemental analysis and various spectroscopic techniques. Interaction of complexes 1 and 2 with the biomolecules viz. HSA (human serum albumin) and DNA were studied using absorption titration, fluorescence techniques, and in silico molecular docking studies. The results exhibited the significant binding propensity of both complexes 1 and 2, but complex 1 showed more avid binding to HSA and DNA. Also, the nuclease activity of 1 and 2 was analyzed for pBR322 DNA, and the results obtained confirmed the potential of the complexes to cleave DNA. Moreover, the mechanistic pathway was studied in the presence of various radical scavengers, which revealed that ROS (reactive oxygen species) are responsible for the nuclease activity in complex 1, whereas in complex 2, the possibility of hydrolytic cleavage also exists. Furthermore, the cytotoxicity of the ligand and complexes 1 and 2 were studied on a panel of five different human cancer cells, namely: HepG2, SK-MEL-1, HT018, HeLa, and MDA-MB 231, and compared with the standard drug, cisplatin. The results are quite promising against MDA-MB 231 (breast cancer cell line of 1), with an IC50 value that is nearly the same as the standard drug. Apoptosis was induced by complex 1 on MDA-MB 231 cells predominantly as studied by flow cytometry (FACS). The adhesion and migration of cancer cells were also examined upon treatment of complexes 1 and 2. Furthermore, the in vivo chronic toxicity profile of complexes 1 and 2 was also studied on all of the major organs of the mice, and found them to be less toxic. Thus, the results warrant further investigations of complex 1.

Two new complexes of copper(II), [CuL2], and zinc(II), [ZnL2], with a tridentate –ONN′– Schiff base ligand (L), a bioactive scaffold derived from 2-aminobenzimidazole and 2-hydroxy-3-methoxybenzaldehyde, were synthesized and characterized using various spectroscopic techniques, viz, IR, 1H and 13C NMR, EPR, HRMS, and elemental analysis and purity analysis using UPLC studies. Both the complexes are non-electrolytic by nature. The newly synthesized compounds were screened for acetic acid-induced analgesic and yeast-induced antipyretic activities in mice and carrageenan-induced paw edema in rats (anti-inflammatory). The results showed that the [CuL2] compound (at 100 mg kg−1 b.w) possessed potent anti-inflammatory activity whereas [ZnL2] (at 50 mg kg−1 and 100 mg kg−1 b.w) exhibited significant analgesic activity when compared with standard drugs. Both the complexes have apparently moderate and nearly akin antipyretic activity.

Hyperglycaemic conditions facilitate the glycation of serum proteins which may have predisposition to aggregation and thus lead to complications. The current study investigates the glycation induced structural and functional modifications of chickpea cystatin (CPC) as well as biological toxicity of the modified protein forms, using CPC-glucose as a model system. Several structural intermediates were formed during the incubation of CPC with glucose (day 4, 8, 12, & 16) as revealed by circular dichroism (CD), altered intrinsic fluorescence, and high ANS binding. Further incubation of CPC with glucose (day 21) formed abundant β structures as revealed by Fourier transform infrared spectroscopy and CD analysis which may be due to the aggregation of protein. High thioflavin T fluorescence intensity and increased Congo red absorbance together with enhanced turbidity and Rayleigh scattering by this modified form confirmed the aggregation. Electron microscopy finally provided the valid physical authentication about the presence of aggregate structures. Functional inactivation of glucose incubated CPC was also observed with time. Single cell electrophoresis of lymphocytes and plasmid nicking assays in the presence of modified CPC showed the DNA damage which confirmed its biological toxicity. Hence, our study suggests that glycation of CPC not only leads to structural and functional alterations in proteins but also to biotoxic AGEs and aggregates.