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The existing work demonstrated the successful synthesis of WO₃ nanoparticles in one-pot system via self-assembly synthesis using triton-X as non-ionic polymer templating agent. The fast and efficient method was achieved by ultrasound irradiation. Characterization by using XRD, FTIR, XPS, UV-DRS, SEM, TEM and HRTEM demonstrated the formation of pure WO₃ having particle size of 10–25 nm. With the band gap energy of 2.25 eV, the prepared nanoparticles showed excellent photocatalytic performance towards tetracycline photooxidation with removal of 91.84 % during 60 of treatment.

Alzheimer's disease (AD) is a neurological illness. AD is often treated with rivastigmine (RV). The present study developed trilayer dissolving microneedle (TDMN) RV delivery system to overcome challenges in RV conventional forms. To enable the assessment of TDMN by ex vivo and in vivo methods, we developed a UV–Visible spectrophotometric method to quantify RV in four media using cobalt thiocyanate as a derivatization reagent. Guidelines set by the International Conference on Harmonization (ICH) were used to validate this approach. Results indicate a correlation coefficient of 0.9999 for all media, with the lower limit of quantification values for Phosphate Buffer Saline, rats’ plasma, skin, and brain matrices were 1.29, 0.67, 0.67, and 0.89 µg/mL, respectively. Significantly, the method is precise and accurate. Finally, to support this study's objective, TDMN formulation was developed, and direct application of the proposed method for quantifying RV in ex vivo and in vivo studies was conducted.

Contamination of water by toxic transition metal ions is increasing gradually. These metal ions cause various types of diseases. Therefore, some sew chemo-sensors 4,4′-((1E,1′E)-(propane-2,2-diylbis(4,1-phenylene))bis(diazene-2,1-diyl))bis(3,5-dihydroxybenzoic acid), [4,4′-((1E,1′E)-(oxybis(4,1-phenylene))bis(diazene-2,1-diyl))bis(3,5-dihydroxybenzoic acid), 4,4′-((1E,1′E)-(sulfonylbis(4,1-phenylene))bis(diazene-2,1-diyl))bis(3,5-dihydroxybenzoic acid), (E)-4-((4-(4-(2-(4-(4-carboxy-2,6-dihydroxyphenoxy)phenyl)propan-2-yl)phenoxy)phenyl)diazenyl)-3,5-dihydroxybenzoic acid] were synthesized and characterized by TLC, UV–Visible spectrophotometry, FTIR, and NMR techniques. The synthesized chemo-sensors exhibited the best performance in sensing the various types of transition metal ions by simply color variation. The detection of metal ions was also monitored by UV–Visible spectrophotometry through shifting in λ_max of chemo-sensors caused by interactions.

This research aimed to evaluate the chemical quality, antioxidant, and antimicrobial (antibacterial and antifungal) activity of essential oils (EOs) from three species of Eucalyptus: E. botryoides, E. cladocalyx, and E. grandis. The identification of the chemical profile of these essential oils revealed that 1,8-cineole, α-pinene, and β-(Z)-ocimene constitutes the significant compounds of these EOs. The antioxidant power tests of the essential oils of E. grandis and and E. cladocalyx shows a strong scavenging activity of the DPPH free radical with a percentage of 80.83 % and 80.46 % respectively at the concentration of 160 mg/mL, results confirmed by the FRAP test. As for the antimicrobial activity, the essential oils significantly inhibited the growth against all the strains studied. E. cladocalyx EOs were preferentially effective against fungi at the minimum inhibitory concentration of 1/2000 v/v, then E. grandis EOs were more effective against bacteria and fungi at the minimum inhibitory concentration of 1/1000 v/v. Finally, E. botryoides EO is less effective against the tested microbial strains.

A 1:1 cocrystal of 4-oxo-4-(pyridin-2-ylamino)butanoic acid (APS) and benzoic acid (BA), APS-BA (1:1), was prepared and characterized by Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA), Infrared (FT-IR), powder X-ray diffraction (PXRD) and single crystal X-ray diffraction (SCXRD) studies. Crystal structure reveals that APS-BA (1:1) is formed by joint N-H…O and O-H…N hydrogen bonding between APS and BA molecule resulting in a hetero-dimeric R²₂(8) motif. A pair of C-H…O interactions and another pair of O-H…O hydrogen bonds between APS molecules ensures formation of a one-dimensional zig-zag hydrogen bonded tape of APS molecules, with the BA molecules occupying pendant position. Hirshfeld surface analysis including energy framework and lattice energy calculations were performed and compared with those of the components APS and BA. Comparison of the computed energetics of individual interactions and the lattice energies showed that cocrystal formation is thermodynamically favoured.

Thiazolidin-4-one sixteen analogues (1–16) were synthesized, characterized and tested against urease inhibitory potential. All synthesized analogues showed varied degrees of IC₅₀ values from excellent to good potency as compared to standard thiourea. Analogues 8, 7 and 5 were the most potent analogue with IC₅₀ values 1.10 ± 0.20, 2.30 ± 0.30 and 4.50 ± 0.10 µM respectively among the series. These analogues showed many folds better potency as compared to standard thiourea. All other analogues also showed excellent potency which was many folds better than standard thiourea. Structure-activity relationship was established and binding interactions of the most potent analogues were confirmed through molecular docking studies.

Kinetics of isosorbide (S) oxidation by Ce(IV) in aqueous HClO₄ medium has been examined via spectrophotometric technique at fixed ionic strength and temperature. The reaction showed a 1: 2 stoichiometry (S: Ce(IV)). The reaction was studied under pseudo-first order conditions. The dependency of the rate of oxidation reaction on the reactants’ concentrations showed that the reaction was first order in [Ce(IV)], whereas in both [H⁺] and [S], its order was lower than unity. The oxidation rate was directly proportional to ionic strength as well as dielectric constant of the reaction medium. However, it should be mentioned that adding Ce(III) had remarkably not affect the rate. The isosorbide oxidation product was recognized as (1S,4S,5R)-4-hydroxy-2,6-dioxabicyclo[3.3.0]octan-8-one). A mechanistic scheme for oxidation coherent with the observed kinetics was proposed. The rate-law expression was derived which was agreed with the acquired outcomes. The calculated activation quantities recommended construction of a rigid intermediate through the reaction and such process was endothermic and non-spontaneous.

The titled salt was synthesized by adding 2-Amino-4-methyl pyridine and Oxalic acid at 1:1 ratio, crystallizes in P2₁/n space group. The crystal structure of the salt 2-amino-4-methylpyridinium oxalate has been determined from the single crystal X-ray analysis. The crystal structure reveals that a protonation process took place in the solid; this confirms the compound is a salt. The molecular structure of the salt forms hydrogen bonding interactions in the crystal. The crystal structure is stabilized by N–H···O and C–H···O type of interactions. The Hirshfeld surface and 2D fingerprint plot analysis has been performed to understand the weak and strong interactions of the salt molecule. The nitrogen atoms N1 and N2 of 2A4MP are hydrogen bonded with a carboxyl group of oxalate forms a $R_2^2$(8) ring motif via intermolecular interactions N1–H1A···O1, N2–H2B···O2. The QTAIM analysis of electron density at the critical points of intermolecular interactions shows the charge density distribution of weak and strong interactions. The in-silico ADME predicts that the salt exhibits the drug-likeness property, high bioavailability and high gastrointestinal absorption.

The following study explores the potential use of Marrubium vulgare L. essential oil as a plant-based anticorrosion agent against copper in 0.5 M H₂SO₄. Through electrochemical experiments, the oil significantly reduces copper deterioration in this sulfurous atmosphere. Based on of potentiodynamic polarization curves, Marrubium vulgare L. has a 95.51 % efficiency in preventing corrosion at a concentration of 1 g/l oil. An appropriate electrical circuit model is employed to calculate electrochemical impedance characteristics. The Surface investigation (SEM/EDX) identifies a protective layer on the copper substrate, significantly blocking active copper corrosion sites.

The surface components of mild steel used in field applications are always subject to wear and corrosion attacks. Epoxy coatings serve to improve the surface properties of mild steel; nonetheless, they do not deliver a multiplexed advantage compared to their coating with inert non-metallic particles. The parametric addition of maize cob ash nanoparticles modified with 0.5 wt% silver nanoparticles in the epoxy coating of mild steel was investigated. The coating was done using the spraying method. The transmission and scanning electron microscope, X-ray diffraction and electrochemical test in mixed acid environment were used in the characterization of the developed composites coating. A 42.86 and 96.16 % improvement in hardness values and corrosion resistance of mild steel was obtained at modified 8 wt% maize cob ash nanoparticles/epoxy coating. The corrosion potential of the coated samples tends to be higher, whereas that of the uncoated mild steel is lower. This study demonstrates that epoxy-8 wt% maize cob ash nanoparticles modified with 0.5 wt% silver nanoparticles can be used to enhance the anti-corrosion of mild steel in a mixed acid environment.