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A simplified synthetic approach involving sulfonylation followed by amino group alkylation produced new 2-aminothiazole derivatives. UV/Vis, infrared, and NMR spectroscopies confirmed their structures. Compounds 36, 22, 34, and 35 showed strong inhibition against Jack bean and Bacillus Pasteurii urease, with IC50 values from 14.06 to 20.21 µM/mL. Compounds 20, 26, 21, 29, 30, 31, and 32 exhibited potent inhibitory effects against α-glucosidase and α-amylase, with IC50 values between 20.34 and 37.20 µM/mL. Compounds 33, 26, and 27 demonstrated potent DPPH scavenging, with IC50 values around 34.4-39.2 µM/mL. FMO analysis showed compounds 21, 22, 24, and 25 having parallel aromatic ring systems due to π cloud interactions, while compounds 32 and 38 had distinct electronic density distributions. Compound 22 had HOMO and LUMO energy gaps of 5.805 eV, with bromo and fluoro substitutions in compounds 21 and 24 slightly increasing the gaps to 6.089 eV and 6.078 eV, respectively. Nitro groups in compounds 25 and 32 reduced the gaps to 0.384 eV and 1.187 eV. All compounds demonstrated high gastrointestinal absorption, non-permeability to the blood-brain barrier, and optimal skin permeation (Log Kp between -5.83 and -6.54 cm/s). Compounds 22, 24, and 38 had promising QED scores of 0.719, 0.707, and 0.860, respectively, with synthetic accessibility scores from 2.057 to 2.517. ADMET predictions indicated minimal toxicity, cardiovascular safety, and significant inhibitory potential for CYP enzymes. Strong in silico binding affinities (binding energies -5.75 to -7.63 kcal/mol) and metabolic stability suggest these derivatives are promising candidates for further drug development.
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In this work, chemical modification of the chitosan with ethyl acetoacetate was performed through a base-catalyzed reaction in which epichlorohydrin facilitated the insertion as well as nucleophilic substitution reaction to graft the 1,3-dioxo moiety across the linear chains of the base biopolymer to establish specificity and selectivity for U(VI) removal. The modified chitosan (EAA-CS) was intercalated into phosphate rich alginate matrix (PASA). Later on, the WO3-doped composites with different WO3 to PASA mass ratio were prepared and characterized using FTIR, XPS, SEM-EDS, XRD, and elemental mapping analysis. WO3 significantly contributed to chemically stable inorganic-organic composites with improved porous texture. Among the prepared composites, MCPS-3 microspherical beads, having mass ratio of 30.0 % w/w, exhibited excellent sorption capacity for U(VI) at an optimal pH 4.5. The successful U(VI) sorption was validated by the existence of two U4f peaks at 392.25 and 381.36 eV due to U4f5/2 and U4f7/2 sub-peaks with an intensity ratio of 3:4, respectively. Batch mode sorption kinetics followed pseudo-second-order rate equation (R2 ≈ 0.99, qe,th ≈ 116.88 mg/g, k2 = 0.86 × 10-4 g/mg.min-1) and equilibrium sorption data aligns with Langmuir (R2 = 0.99, qm = 343.85 mg/g at 310 K and pH = 4.5, KL = 2.00 × 10-2 L/mg) and Temkin models (R2 ≈ 0.99). Thermodynamic parameters ΔHo (30.51 kJ/mol), ΔSo (0.19 kJ/mol.K) and ΔGo (-25.64, -26.89, and - 27.91 kJ/mol) at 298, 305, and 310 K, respectively, suggested that the uptake process is feasible, endothermic and spontaneous. Based on these findings, it is reasonable to conclude that MCPS-3 could be a better hydrogel-based biomaterial for appreciable uranium recovery.
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Alginatos , Quitosano , Óxidos , Ácido Fítico , Tungsteno , Uranio , Quitosano/química , Alginatos/química , Adsorción , Tungsteno/química , Óxidos/química , Ácido Fítico/química , Uranio/química , Cinética , Concentración de Iones de Hidrógeno , Purificación del Agua/métodosRESUMEN
In this work, novel monoclinic tungsten oxide (WO3)-encapsulated phosphate-rich porous sodium alginate (PASA) microspherical hydrogel beads were prepared for efficient U(VI) capture. These macroporous and hollow beads were systematically characterized through XRD, FTIR, EDX-mapping, and SEM-EDS techniques. The O and P atoms in the PO and monoclinic WO3 offered inner-spherical complexation with U(VI). The in situ growth of WO3 played a significant role inside the phosphate-rich biopolymeric network to improve its chemical stability, specific surface area, adsorption capacity, and sorption rate. The phytic acid (PA) served for heteroatom doping and crosslinking. The encapsulated WO3 mass ratio was optimized in different composites, and WO3/PASA3 (the microspherical beads with a mass ratio of 30.0 % w/w) exhibited remarkable maximum sorption capacity qm (336.42 mg/g) computed through the best-fit Langmuir model (R2 ≈ 0.99) and rapid sorption equilibrium, teq (150 min). The isothermal sorption studies were conducted at different temperatures (298, 303, and 308 K) and thermodynamic parameters concluded that the process of U(VI) sorption using WO3/PASA3 is endothermic and feasible having ΔHo (8.19 kJ/mol), ΔGo (-20.75, -21.38, and - 21.86 kJ/mol) and proceeds with a minute increase in randomness ΔSo (0.09 kJ/mol.K). Tungsten oxide (WO3)-encapsulated phosphate-rich porous microspherical beads could be promising material for uranium removal.
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Alginatos , Óxidos , Tungsteno , Uranio , Alginatos/química , Adsorción , Fosfatos , Porosidad , Termodinámica , Cinética , Uranio/química , Concentración de Iones de HidrógenoRESUMEN
The current research work focuses on the extraction and optimization of the hydrogel (AVM) from the seeds of Artemisia vulgaris using Box-Behnken design-response surface methodology (BBD-RSM). The AVM was obtained through a hot water extraction process. The influence of different factors, including pH (U = 4 to 10), temperature (V = 25 to 110 °C), seed/water ratio, i.e., S/W ratio (W = 1/10 to 1/70 w/v), and seed/water contact time, i.e., S/W time (X = 1 to 12 h) on the yield of AVM was evaluated. The p-value for the analysis of variance (ANOVA) was found to be <0.001, indicating that the yield of AVM mainly depended on the abovementioned factors. The highest yield of AVM, i.e., 15.86%, was found at a pH of 7.12, temperature of 80.04 °C, S/W ratio of 1/33.24 w/v, and S/W time of 8.73 h according to Design-Expert Software. The study of the pH-responsive behavior of AVM in tablet form (formulation AVT3) revealed that AVM is a pH-responsive material with significantly high swelling at pH 7.4. However, less swelling was witnessed at pH 1.2. Moreover, AVM was found to be a sustained release material for esomeprazole at pH 7.4 for 12 h. The drug release from AVT3 was according to the super case-II transport mechanism and zero-order kinetics.
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In this study, an innovative approach is followed to synthesize graft copolymerized chitosan with acetylacetone (AA-g-CS) through free-radical induced grafting. Afterwards, AA-g-CS and rutile have been intercalated uniformly into amino carbamate alginate matrix to prepare its biocomposite hydrogel beads of improved mechanical strength having different mass ratio i.e., 5.0 %, 10.0 % 15.0 % and 20.0 % w/w. Biocomposites have been thoroughly characterized through FTIR, SEM and EDX analysis. Isothermal sorption data showed good fit with Freundlich model as conferred from regression coefficient (R2 ≈ 0.99). Kinetic parameters were evaluated through non-linear (NL) fitting of different kinetic models. Experimental kinetic data exhibited close agreement to quasi-second order kinetic model (R2 ≈ 0.99) which reveals that chelation between heterogeneous grafted ligands and Ni(II) is occurring through complexation. Thermodynamic parameters were evaluated at different temperatures to observe the sorption mechanism. The negative values of ΔG° (-22.94, -23.56, -24.35 and - 24.94 kJ/mol), positive ΔH° (11.87 kJ/mol) and ΔS° (0.12 kJ/molK-1) values indicated that the removal process is spontaneous and endothermic. The maximum monolayer sorption capacity (qm) was figured as 246.41 mg/g at 298 K and pH = 6.0. Hence, 3AA-g-CS/TiO2 could be better candidate for economic recovery of Ni(II) ions from waste effluents.
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Quitosano , Contaminantes Químicos del Agua , Quitosano/química , Alginatos/química , Adsorción , Termodinámica , Cinética , Agua , Concentración de Iones de HidrógenoRESUMEN
The main objective of this study was to examine the impact of cellulose nanocrystals (CNCs) in advanced waterborne wood coatings such as polycarbonate urethane (PCU) and hybrid alkyd varnish (HAV) in terms of coating performance, mechanical properties, optical properties, and water permeation and uptake properties. The influence of CNCs on the overall quality of the various waterborne wood coatings was investigated by incorporating different percentages of CNCs. Varying CNC content in coating formulations showed that CNCs are effective for waterborne wood coatings; CNCs offer both higher scratch and impact resistance as compared to neat coatings and have a significant reduction in water vapor permeation through a film with little increase in water vapor uptake at high concentrations. It was observed that the CNC darkened and reduced gloss in the coatings and viscosified the dispersion. These research findings suggest that CNCs are well-dispersed at lower concentrations, but at high concentrations, agglomeration occurred. Thus, while CNCs can give better mechanical and permeation performances at contents of up to 5 wt %, at 1 wt % CNCs can still provide modest scratch and chip resistance improvement without loss of optical properties (gloss and color) while retaining a similar water uptake. Overall, it can be concluded that CNCs have the potential to be used as a reinforcement filler in high-performance waterborne wood coatings.
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In this research work, a hybrid biocomposite based on N-maleated chitosan, amino-thiocarbamate functionalised calcium alginate and anhydrous Titania nanoparticles (NMC-MCA-TiO2) was fabricated. The study involves the one pot facile synthesis of N-maleated chitosan and amino-thiocarbamate functionalised alginate under moderate conditions. Sorbent was conditioned in the form of hydrogel beads and characterized through FT-IR and SEM analysis. Newly grafted functional groups could act as potential chelating sites for enhanced Cu(II) sorption. Modified biopolymers were organo-functionalised which provided excellent support for immobilization of Titania nanoparticles (TiO2) as inorganic filler. Kinetic data illustrated the manifestation of intrinsic chemisorption instead of simple bulk/film diffusion. Equilibrium sorption data fitted well with Freundlich adsorption model (R2 ≈ 0.99) which designated the heterogeneous nature of sorbent. Maximum sorption capacity of biosorbent was found 192 mg/g at 298 K and pH = 6.0. Standard Gibbs free energy change ∆Go (-21.53, -21.97, and - 22.42 kJ/mol), standard enthalpy change ∆Ho (5.12 kJ/mol) and standard entropy change ∆So (0.09 kJ/mol K-1) values suggested that the sorption process to be spontaneous and endothermic. The sorbent 3NMC-MCA-TiO2 could be competitive candidate for economical and rapid adsorptive removal of Cu(II) from dilute contaminated liquids.
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Quitosano , Contaminantes Químicos del Agua , Adsorción , Alginatos/química , Quitosano/química , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , TitanioRESUMEN
Mixed superalkali clusters are a source of excess electrons, as their vertical ionization energies (2.81-3.36 eV) are much lower than those of alkali metals (even cesium (â¼3.85 eV)) and the superalkali Li3O (3.42 eV). In the present work, the geometric, electronic, and nonlinear optical (NLO) properties of mixed superalkali cluster-doped B12N12 nanocages are studied theoretically. All complexes, A-G, have very high interaction energies (-98.02 to -123.13 kcal mol-1) and are thermodynamically stable when compared to previously reported Li3O@B12N12 (-92.71 kcal mol-1). The designed complexes have smaller HOMO-LUMO energy gaps (3.36-4.27 eV) than pristine B12N12 (11.13 eV). Charge transfer in the complexes is studied through natural population analysis and non-bonding interactions are evaluated through quantum theory of atoms in molecules (QTAIM) and non-covalent interaction analyses. These complexes have absorption maxima (1076-1486 nm) in the near-infrared region (NIR) and they are transparent in the UV region. The first hyperpolarizability of complex C is 1.7 × 107 au, which is much higher than the value of 3.7 × 104 au for a pure Li3O superalkali-doped B12N12 complex calculated at the same level of theory, as reported by Sun et al. (Dalton Trans., 2016, 45, 7500-7509). The large second hyperpolarizability values also reflect the enhanced nonlinear optical response. The best computed values for the electro-optical Pockels effect, second harmonic generation, and hyper-Rayleigh scattering are 3.29 × 1010 au, 1.17 × 1010 au, and 6.71 × 106 au, respectively. Furthermore, the electro-optic dc-Kerr effect and electric-field-induced second harmonic generation have maximum values of 3.96 × 1011 au and 3.46 × 1010 au at 1064 nm. There are enhancements in the quadratic nonlinear refractive index (n2) values for complexes A-G, with a highest n2 value of 3.35 × 10-8 cm2 W-1 at 1064 nm. These results suggest that mixed-superalkali-doped B12N12 nanoclusters are potential candidates when designing high-performance NLO materials.
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The present study is based on the synthesis of a novel hybrid biosorbent using 1,2-cyclohexylenedinitrilotetraacetic acid modified crosslinked chitosan and amino-thiocarbamate moiety functionalized sodium alginate (CDTA-CS/TSC-CA). The fabricated sorbent was employed to investigate the efficient recovery of Cu(II) from aqueous media. CDTA-CS/TSC-CA was characterized using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Analysis confirmed the successful modification of both biopolymers and subsequent loading of Cu(II) ions. CDTA-CS/TSC-CA was casted in the form of hydrogel beads having different CDTA-CS to TSC-CA mass ratios i.e., 10.0-40.0% by mass. The hydrogel beads 4CDTA-CS/TSC-CA with CDTA-CS/TSC-CA mass ratio of 40.0% was found most effective for copper sorption. Equilibrium sorption results showed that initial concentration of copper, medium pH, contact time, sorbent dosage and temperature influenced the sorption capacity (qe). Rate of sorption data was interpreted using different kinetic models and found best fitted with pseudo second order rate expression (R2 ≈ 0.99), illustrating that the rate determining step includes the electron density transfer from sorbent coordination sites to central copper ions. Crank's RIDE equation and Elovich chemisorption model (ECM) revealed the presence of two sorption phases, initially rapid sorption followed by comparatively a slow uptake. Equilibrium sorption data was well depicted by Langmuir model and maximum monolayer adsorption capacity (qm) was computed as 276.53 mg·g-1 at 298 K. Standard Gibbs free energy change, ∆G° (-19.99, -20.18 and -20.36 kJ/ mol), standard enthalpy change, ∆H° (-8.95 kJmol) and standard entropy change, ∆S° (0.04 kJ/mol K-1) values suggested that the adsorption process is spontaneous and exothermic. Hence, 4CDTA-CS/TSC-CA was found efficient biosorbent for copper removal from its dilute effluents.
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Quitosano , Contaminantes Químicos del Agua , Adsorción , Alginatos/química , Quitosano/química , Cobre/química , Hidrogeles/química , Concentración de Iones de Hidrógeno , Iones , Cinética , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
In this study, organo-funtionalization of sodium-alginate has been carried out using phenylsemicarbazide as modifier to graft N, O-donor atoms containing functional groups (amino-carbamate moieties) to offer novel support for TiO2 immobilization. Hybrid composite made of aminocarbamated alginate, carboxymethyl chitosan (CMC) and titanium oxide TiO2 (MCA-TiO2) was prepared for the promising adsorptive remediation of Ni(II). FT-IR, SEM-EDX were employed to characterize MCA-TiO2. The optimization of TiO2 to modified alginate mass ratio was carried out and hydrogel beads with TiO2/MCA mass ratio of 10.0% (2MCA-TiO2) revealed highest sorption efficiency. The produced sorbents were adapted in the form of hydrogel beads for operation. Organic functionalization based on aminocarbamate (OCONHNH2) moieties on linear chains of alginate embedded additional chelating functional sites which enhanced sorption and selectivity. Batch mode experiments were conducted for optimization of pH and sorbent dose. Equilibrium sorption, kinetic and thermodynamic studies were performed to pattern the nature of sorption. Kinetic data was found in close agreement with pseudo-second order rate expression (PSORE). Isothermal equilibrium sorption data was well fitted with Langmuir adsorption model. Maximum sorption capacity was evaluated as 229 mg/g at 298 K and pH = 6.0.
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Alginatos/química , Quitosano/química , Nanocompuestos/química , Níquel/química , Titanio/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Estructura Molecular , Nanocompuestos/ultraestructura , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
In the current study, cellulose was extracted from the plant dunchi fiber by using an ecofriendly method followed by preparation of nanocellulose. The procedure involved an alkali treatment and chlorine-free bleaching for removal of lignin and hemicelluloses from material. Fourier transform infrared (FTIR) spectroscopy provided the evidence about removal of hemicellulose and lignin. The morphological changes in the surface of lignocellulosic fibers were studied through scanning electron microscopy (SEM). X-ray Diffraction (XRD) analysis measured the degree of crystallinity of extracted cellulosic material. By using Segal method, the degree of crystallinity was found 66.7%. Crystal thickness was determined by Scherrer equation and its value was found to be 40.07 Å. The values were closed to the values observed for commercial microcrystalline cellulose (MCC). The TGA curve showed the thermal degradation pattern of the cellulosic material and it was closed to the thermal behavior of pure cellulose. Finally, nanocellulose was produced by acid hydrolysis from the obtained cellulosic material. Transmission electron microscopy (TEM) showed the existence of nanocellulose with an average aspect ratio of 10.45 ± 3.44. In the future, dunchi fiber has a potential to be used as a renewable source to produce cellulose and subsequently its nanocellulose for a wide range of applications in composite materials.
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Celulosa/química , Polisacáridos/química , HidrólisisRESUMEN
A novel hybrid biocomposite based on amino-thiocarbamate derivative of alginate, carboxymethyl chitosan and TiO2 (TiO2/TSC-CMC) was fabricated and characterized using Fourier transform Infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDX). The TiO2/TSC-CMC mass ratio (5.0-30.0%) was optimized and 3TiO2/TSC-CMC (hydrogel beads with TiO2/TSC-CMC mass ratio of 20.0%) was selected as the best sorbent for effective biosorption of Ni(II). Batch sorption experiments were conducted, instantaneous and equilibrium sorption capacities were investigated as function of pH, sorbent dose, initial metal concentration, contact time and temperature. Kinetic data could be well explained through pseudo second order rate equation (PSORE) depicting that the rate determining step involves the transfer of electron density from sorbent functional sites to central metal ion. Langmuir model fitted well with isothermal sorption data and maximum monolayer sorption capacity (qm) was computed as 172 mg/g at pH 6.0 and temperature 298 K. The values of thermodynamic parameters such as standard enthalpy change (16.94 kJ/mol) and standard Gibbs energy change (-18.67, -19.48, -20.57, and -21.38 kJ/mol) and standard entropy change (0.12 kJ/mol·K) concluded that sorption process is endothermic, spontaneous and resulted with increase in randomness. Hence, 3TiO2/TSC-CMC was found efficient and reusable sorbent.
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Alginatos/química , Materiales Biocompatibles/química , Quitosano/análogos & derivados , Quitosano/química , Níquel/química , Tiocarbamatos/química , Titanio/química , Adsorción , Hidrogeles/química , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Temperatura , TermodinámicaRESUMEN
The present work is focused on pyrolysis of polystyrene waste for production of combustible hydrocarbons. The experiments were performed in an indigenously made furnace in the presence of a laboratory synthesised copper oxide. The pyrolysis products were collected and characterised. The Fourier transform infrared spectra showed that the liquid fraction contains C-H, C-O, C-C, C=C and O-H bonds, which correspond to various aliphatic and aromatic compounds. Gas chromatography-mass spectrometry traced compounds ranging from C1 to C4 in the gaseous fraction, whereas in the liquid fraction 15 components ranging from C3 to C24 were detected. From the results it has been concluded that CuO as a catalyst not only increased the liquid yield but also reduced the degradation temperature to great extent. Fuel properties of the pyrolysis oil were determined and compared with standard values of commercial fuel oil. The comparison suggested potential application of pyrolysis oil for domestic and commercial use.
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Poliestirenos , Pirólisis , Catálisis , Cobre , Calor , Hidrocarburos , ÓxidosRESUMEN
In present study, pure and amino-carbamate moiety grafted calcium alginate hydrogel beads (CA, PSC-CA) were prepared for their biosorption performance in the recovery of silver ions. The produced sorbents were characterized using FTIR, SEM, EDX and TGA. FTIR and SEM-EDX confirmed the successful modification and loading of silver ions onto hydrogel beads. When compared with CA, PSC-CA showed enhanced sorption but comparable kinetics. Equilibrium sorption studies showed that pH, sorbent dose, contact time and adsorbate concentration influenced the sorption capacity. The uptake kinetic data was well demonstrated by pseudo second order rate equation (PSORE). Elovich equation and the resistance to intra-particle diffusion model (RID) suggested that there were two phases of sorption, first one was rapid followed by relatively slow uptake step. Equilibrium isothermal sorption data was well fitted by Langmuir and Sips models. The separation factor RL was found as 0 < RL < 1 which indicated favourable sorption. The maximum monolayer sorption capacity was computed as 210 mg/g at 298 K. Thermodynamic studies revealed the sorption process to be spontaneous and exothermic. PSC-CA hydrogel beads were found as cost-effective and efficient sorbent for economically-competitive recovery of Ag(I).
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Alginatos/química , Carbamatos/química , Hidrogeles/química , Plata/química , Iones , Cinética , Termodinámica , AguaRESUMEN
Benzocaine is well-known for its role as an anesthetic agent and largely used in oral ulcers, ear pain and dental complications. Along with lidocaine and other local anesthetics, benzocaine has marked it as an anesthetic agent in surgical procedures and as Na+ channels blocker, as well. Analogues of benzocaine have been found to possess biological potentials including antibacterial, antifungal and anti-cancer. Some derivatives were found to have conspicuous action against tuberculosis. The current review focuses to explore the century-long potential of the molecule and its analogs that have appeared in the literature. Furthermore, highlighting the biological potential of benzocaine and its analogues shall open-up new dimensions of future research to design more potent analogues.
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Anestésicos Locales/química , Anestésicos Locales/farmacología , Benzocaína/análogos & derivados , Benzocaína/farmacología , Desarrollo de Medicamentos , Anestésicos Locales/uso terapéutico , Animales , Antiinfecciosos/química , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Benzocaína/uso terapéutico , Desarrollo de Medicamentos/métodos , Descubrimiento de Drogas/métodos , HumanosRESUMEN
The quinolinyl chalcones series (A1-A14) were screened for antimalarial activity. According to in vitro antimalarial studies, many quinolinyl chalcones are potentially active against CQ-sensitive and resistance P. falciparum strains with no toxicity against Vero cell lines. The most active quinolinyl chalcones A4 (with IC50 0.031 µM) made a stable A4-heme complex with - 25 kcal/mole binding energy and also showed strong π-π interaction at 3.5 Å. Thus, the stable A4-heme complex formation suggested that these quinolinyl chalcones act as a blocker for heme polymerization. The docking results of quinolinyl chalcones with Pf-DHFR showed that the halogenated benzene part of quinolinyl chalcones made strong interaction with Pf-DHFR as compared to quinoline part. A strong A4-Pf-DHFR complex was formed with low binding energy (- 11.04 kcal/mole). The ADMET properties of quinolinyl chalcones were also studied. The in vivo antimalarial studies also confirmed the A4 as an active antimalarial agent.
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Antimaláricos/química , Antimaláricos/farmacología , Chalconas/química , Chalconas/farmacología , Plasmodium falciparum/efectos de los fármacos , Animales , Chlorocebus aethiops , Hemo/metabolismo , Humanos , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/metabolismo , Simulación del Acoplamiento Molecular , Plasmodium falciparum/metabolismo , Proteínas Protozoarias/metabolismo , Quinolinas/química , Quinolinas/farmacología , Tetrahidrofolato Deshidrogenasa/metabolismo , Células VeroRESUMEN
Poly(N-isopropylacrylamide-co-acrylamide) (PNA-BIS-2) microgels were synthesized by free radical precipitation polymerization in aqueous medium. Spherical Ag nanoparticles with diameter of 10-20â¯nm were fabricated inside the PNA-BIS-2 microgels by in-situ reduction of silver nitrate using sodium borohydride as reducing agent. The Ag nanoparticles- loaded hybrid microgels were characterized by Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Energy dispersive X-ray (EDX), Scanning transmission electron microscopy (STEM), Ultraviolet visible spectroscopy (UV Visible), Thermogravimetric analysis (TGA) and X-ray diffraction (XRD). Ag contents in the hybrid system were determined by inductively coupled plasma - optical emission spectrometry (ICP-OES). Various nitroarenes were successfully converted into their respective aromatic amines with good to excellent yields (ranging from 75% to 97%) under mild reaction conditions. The catalyst has ability to successfully convert substituted nitroarenes into desired products keeping many functionalities intact. The catalyst can be stored for long time without any sign of aggregation and can be used multiple times without any significant loss in its catalytic activity.
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Water contamination is a worldwide critical issue for the present society to avoid competition and maintain an environmentally friendly scenario. Removal of various pollutants including inorganic and organic compounds from water is a big challenge nowadays. Worldwide attention to promote polluted water and technologies related to its treatment has been adversely increased. The utilization of metal/metal oxide nanoparticles (NPs) for this purpose has gained much attention due to its exceptional properties imparted by reduced size and effective surface area. Moreover, metal/metal oxide NPs-based innovation for improved expulsion productivity is an ingenious area for research and development but the use of such NPs presents some serious risks. Herein, the advanced requisition of NPs for polluted water treatment is highlighted along with the difficulties related to them and their toxic impacts when used as water purifiers. Additionally, the plausible fate of metal/metal oxide NPs incorporated in the water for purification and salient future challenges are deliberated.
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Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Metales/química , Óxidos/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Contaminantes Químicos del Agua/toxicidadRESUMEN
Acrylamide based microgels have gained a lot of attention in the last three decades due to their potential applications in various fields based on their responsive behavior and chemical stability. In this article, the synthesis, properties, and applications of poly(N-isopropylacrylamide-co-acrylamide) [P(NIPAM-Am)] microgels and P(NIPAM-Am) microgels having an additional ionic moiety in their network [P(NIPAM-Am-IM)] are reviewed. These microgels may swell/deswell reversibly with slight changes in environmental conditions such as change in temperature/pH/ionic strength etc. of the medium. This responsive behavior makes the microgels a potential candidate for use in the field of nanotechnology, drug delivery, sensing and catalysis. A critical overview of the recent research progress in this area along with future perspectives is presented. The discussion is concluded with suggested possible future studies for further development in this area.
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Nyctanthes arbor-tristis (NAT) is commonly used traditionally for the treatment of rheumatism and inflammatory diseases. Current study evaluates the antiarthritic potential of NAT using Freund's adjuvant-induced arthritic rat model. Treatments with methanolic, ethyl acetate, and n-hexane extracts were continued for consecutive 20 days. Macroscopic arthritic scoring and water displacement plethysmometry were used to evaluate arthritic development. Hematological and biochemical parameters were investigated and ankle joints were processed for histopathological evaluation. Qualitative phytochemical analysis and GC-MS analysis were conducted for identification of constituents. NAT extracts suppressed arthritic scoring, paw edema, infiltration of inflammatory cells, pannus formation, and bone erosion. The plant extracts ameliorated total leukocytes and platelet counts and nearly normalized red blood cells (RBC) counts and hemoglobin (Hb) content. The extracts were found safe in terms of hepatotoxicity and nephrotoxicity as determined by aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and urea levels. Comparative analysis showed that ethyl acetate extract produced the highest inhibition of paw edema. The major constituents found in ethyl acetate extract can be classified into three major classes, that is, terpenes, terpenoids, fatty acids, and iridoid glycosides. Current study showed that Nyctanthes arbor-tristis ameliorated experimental rheumatoid arthritis and ethyl acetate extract possessed the highest inhibitory activity.