Chemical Physics Impact最新文献

Heavy metal toxicity in water is a serious problem with harmful effects on human health and the ecosystem. This research studied a silicate-based material as an adsorbent for removing four heavy metals from aqueous solutions. The target metal pollutants selected include manganese (Mn²⁺), copper (Cu²⁺), cobalt (Co²⁺), and zinc (Zn²⁺). First, theoretical tools including potential energy surface analysis, Natural Population Analysis, AIM, Wiberg Bond Index, QTAIM, and topological methods offer profound insights into the nature of interactions present in the Mg₂O₈Si₃M (M = Mn²⁺, Cu²⁺, Co²⁺, Zn²⁺) clusters. Second, the synthesis and characterization of eco-friendly hydrated amorphous magnesium silicate (MgOSiO₂nH₂O) was developed. Last, a simple kinetic adsorption test was applied to assess the material selectivity towards heavy metals and support theoretical results. The kinetic adsorption study was analyzed through the pseudo-first and second-order kinetics, Elovich, and the intraparticle diffusion models. The theoretical analysis of the adsorption energies indicates that the adsorption of four metal ions on the Mg₂O₈Si₃ surface is energetically favorable in all cases. The material displayed the following adsorption sequence: Cu²⁺ (59 mg g^-1) > Zn²⁺(25 mg g^-1) ≈ Co²⁺ (23 mg g^-1) > Mn²⁺ (15 mg g^-1). This knowledge can then be used to design and optimize low-cost silicate-based materials for effective heavy metal removal, contributing to efforts to address environmental pollution and protect public health.

A library of chlorophenyl, thiophenyl, and biphenyl clubbed 3′,4,4′,5-tetrahydro-2′H-[1,3′-bipyrazole]-2′-carbaldehydes was produced via aldolic condensation followed by hetero-cyclization. Synthesized moieties were characterized by IR, ¹H, and ¹³CNMR spectral analysis. The molecular docking was conducted utilizing microbial target proteins, 1JX9, and 5C1P to explore the binding interactions of scaffolds. Analogues 4f, 4l, 4r, and 4x exhibited the best docking score of -10.3 kcal/mol with 1JX9 whereas scaffolds 4l and 4o showed maximum docking of -10.4 and -10.2 kcal/mol with target protein 5C1P. Further, scaffolds 4f, 4I, 4l, 4o, 4 u, and 4v showed excellent (pMIC: 1.92 µM/mL) antibacterial activity against S. aureus, B. subtilis, E. coli, P. aeruginosa whereas; analogues 4c, 4l, 4o, 4r, and 4v exhibited admirable (pMIC: 1.92 µM/mL) antifungal activity against R. oryzae fungal strain. Also, analogues were tested for their radical scavenging ability and 4a, 4 g, 4i, 4p, and 4x exhibited good antioxidant activity with 4i standing out as a propitious scaffold with 93.25  % radical scavenging activity. SAR study revealed that biphenyl, 4‑hydroxy-3‑methoxy phenyl, and thiophenyl moieties on the bipyrazole-carbaldehyde scaffold are accountable for virtuous antibacterial, antifungal, and antioxidant activity, respectively. Further in-silico ADME, pharmacokinetic, and toxicity properties were studied, forecasting less-toxic analogues (300 < LD₅₀ ≤ 5000). These findings collectively underscore the potential of the synthesized compounds, with 4l, 4o, 4v and 4x standing out as particularly promising candidates for further exploration.

The present work involves synthesis, characterisation and study of absorption, emission and electrochemical properties of cobalt(III) bis-terpyridine complexes with varying substituent at the 4’-position of the central pyridine ring of terpyridine moiety. The work clearly demonstrates the modulation of the light harvesting window with changing the substituent viz. phenyl, naphthalenyl and thienyltriphenylamine. The naphthalenylterpyridine based cobalt complex shows considerable room temperature luminescence. Cyclic voltammetry data of the complexes reveal a reversible Co^III/II based redox feature. DFT based structure optimisations for all the complexes were performed at the B3LYP level using 6-31G (d,p) and LANL2DZ basis sets. TD-DFT based theoretical calculations were performed with the optimised structures to simulate the experimental absorption spectrum for all the complexes and hence the electronic transitions for the observed absorption peaks were assigned.

This study investigates the antibacterial and antifungal properties of eight benzene sulfonamide derivatives synthesized and reported in our previous study using a combination of experimental and computational methods. In antimicrobial activity, the MIC values of all the eight tested compounds were approximately 125.00 μg/mL against eight bacterial and three fungal strains. However, the compound 8 was found to exhibit remarkable activity (MIC=31.25 μg/mL) against E. faecalis (bacteria) and C. parapsilosis (fungi) compared to the MIC values of rest of the compounds. Results of in-silico drug-likeness and pharmacokinetic (ADMET) assessment reveal that all the title compounds met the compliance of criteria of drug-likeness rules and exhibited zero violations across. Results of docking study demonstrates that the compound 8 showed the highest binding affinity (-8.7 kcal/mol) among the compounds against S. aureus TyrRS, whereas against S. aureus DHFR, compound 2 exhibited the highest binding afinity of -8.5 kcal/mol. Among the compounds docked against C. albicans DHFR and C. albicans N-myristoyl transferase, compound 8 demonstrated the highest binding affinity of -8 kcal/mol and -8.9 kcal/mol, respectively. The results of antibacterial and antifungal experiments substantiate the predictions made by computational studies and provide empirical evidence of antibacterial and antifungal potential of the reported benzene sulfonamide derivatives.

Yttrium Chromate (YCrO₄) nanoparticles (YCNPs) were synthesized using a solution combustion method with a green extract (NeemLeaves extract as a reducing agent. The as-obtained NPs are allowed for calcination at 600 °C. The PXRD pattern showed Bragg reflections confirming the formation of a pure tetragonal phase of YC NPs belonging to the space group I 41/a m d:1. without impurity peaks. The surface morphology revealed smaller, irregularly sized, and shaped NPs with pores and hollows which is the characteristic of solution combustion synthesis. UV–visible spectroscopic analysis confirmed the various absorbance peaks. The energy band gap, determined from Wood and Tauc's plot, was 3.08 eV. FTIR analysis confirmed the presence of specific functional groups in the sample. Electrochemical analysis revealed a specific capacitance range of 61.52 to 40.18 F/g within the scan range of 10 mV/s to 50 mV/s which is due to Increasing scan rate reduces specific capacitance by limiting ion diffusion into deeper pores, favoring interaction with the surface, thus decreasing utilization of active sites and overall capacitance. Collectively, these findings suggest that YCNPs hold promise for practical applications in advanced energy storage devices.

In the present-day nanotechnology is popular in all the fields of technology. The extended application of nanotechnology was utilized in drug delivery, dye absorption, wastewater removal, and in environmental pollutant eradication. However, it is important to follow green synthesis of nanomaterials for safety purposes. In the present study, the zinc nanomaterial was synthesized using a hydrothermal method from Crotalaria pallida leaf extract, which shows that the average size distribution of zinc nanomaterials that have been synthesized was 45 nm and cuboidal in shape. This is identified from the characterization studies that includes X-ray diffraction (XRD), UV–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Field emission scanning electron microscopy (FESEM), and Dynamic Light Scattering (DLS). Thus, the study has identified that the hydrothermal synthesis of nanomaterials is easy to synthesize, feasible and efficient. Some biological assays such as alpha-amylase and alpha-glucosidase inhibition for anti-diabetic activity, cytotoxicity assays for anticancer activities and various other biological assays were carried out for different purposes. All these assays have proved that the nanomaterial extracted from Crotalaria pallida leaf extract has applicability in various fields. Interestingly most of the assays provide increased activity in increased concentration of nanomaterial and proved their therapeutic effect on medicine.

Enzyme-based direct ethanol fuel cells (DEFCs) have the potential to become the next generation of energy devices without platinum catalysts. However, the development of DEFCs requires the search for new electrolytes that are compatible with ethanol fuel and enzymes. In this study, DEFCs with a combination of chitin electrolytes and ADH were fabricated and characterized. DEFCs using chitin electrolyte were also investigated for various ethanol fuel concentrations, and it was found that DEFCs using 50 mM ethanol achieved the highest power density. In addition, enzyme activity was measured and showed a maximum value when 50 mM ethanol was used, suggesting that the proton production reaction catalyzed by the enzyme determines the maximum power density of the bioelectrolyte DEFC. Furthermore, we successfully fabricated a highly portable solid bio-electrolyte DEFC and found that it achieved a maximum power density of 0.11 mW/cm² at an ethanol concentration of 25 %.

This study reports the synthesis and characterization of a novel series of 5-nitro-N-phenyl-3-(phenylamino)-1H-indazole-1-carboxamide derivatives (5a-5v) obtained through the reaction of 3-chloro-5-nitro-N-phenyl-1H-indazole-1-carboxamide (4) with diverse aniline derivatives in isopropanol. The compounds underwent thorough biological evaluation encompassing antibacterial, antifungal, and in addition to antioxidant potential assessed through DPPH (IC₅₀ = 0.105-0.513 μmol/mL) and ABTS assays (IC₅₀ = 0.124-0.538 μmol/mL). Remarkably, compound 5b displayed exceptional antibacterial efficacy, while compounds 5k, 5p, and 5q exhibited noteworthy antifungal potential. Compound 5k showed the most significant antioxidant activity. Molecular docking studies unveiled robust binding interactions with target enzymes (PDB ID: 3SRG), and molecular dynamics simulations indicated the stability of the most active compound at the binding site. Additionally, favourable drug-likeness and ADMET properties underscore the promising therapeutic potential of these derivatives, urging further investigations for potential clinical applications. The multifaceted activities, including antibacterial, antifungal, and antioxidant properties, make these derivatives compelling candidates for in-depth exploration in the pursuit of novel therapeutic agents.

Dynein, a motor protein, harnesses chemical energy from ATP hydrolysis to generate mechanical output as it travels along microtubular tracks. Essential to this process is the microtubule-binding domain (MTBD), which facilitates the interaction with and detachment from microtubules. Previous studies have proposed that the mechanism governing this interaction is primarily driven by the coiled-coil stalk attached to the MTBD. However, conflicting arguments suggest the presence of two-way communications, where the binding and unbinding mechanisms may also influence the nucleotide state of dynein. In this study, we employed all-atom explicit solvent simulations, enhanced sampling techniques, and coarse-grained methodologies to systematically investigate the effects of stalk and MT on the structural stabilities of different conformations of MTBD and their sequence of events during the transition from one to another. We found that the globular MTBD domain without stalk and MT predominantly resides in its weak binding configuration. Upon introduction of a limited length of stalk and interaction with MT, a balance between the strong and weak binding configurations is restored. Further introduction of the full-length stalk and interaction with MT strengthen the kinetic stability of these two configurations. We have also explored the sequence of events of the relevant transition between these two states using coarse-grained simulation protocols both in the presence and absence of interaction with MT. In the absence of MT interactions, we found a mixed conformational state of the system that corresponds to the already published crystal structure of Dynein. In the presence of MT, the conformational change of the stalk precedes the conformational change of the MTBD globular domain. Our findings support the view that the nucleotide state of the AAA+ ring determines the state of the MTBD domain through stalk, shedding light on the intricate mechanisms governing dynein's interaction with microtubules.

Dihydrofolate reductase (DHFR) enzyme regulates de-novo folate synthesis in Plasmodium falciparum, hence a critical malaria drug target. Pyrimethamine inhibits DHFR, but resistance and lack of cross-species activity are key challenges. Therefore, this study is set to investigate more potent nitrogenous heterocyclic compounds against DHFR. Docking and MD simulations were employed to gain insight into the compounds’ binding free energies and conformational stabilities, while cross-species activity was determined using sequence alignment. Among the 500 screened compounds, PMD_01 (−12.2 kcal/mol), PMD_02 (−11.1 kcal/mol), PMD_03 (−10.7 kcal/mol), and PMD_04 (−10.7 kcal/mol) have the highest binding affinities against pfDHFR compared to pyrimethamine (−7.9 kcal/mol). Critical amino acids for binding interactions in the active site of pfDHFR include Leu45, Thr107, Ile164, and Thr170. PMD-bound systems showed higher binding free energy than pyrimethamine, except PMD_03. Hydrogen bonding interactions with Gly159, Ser101, Ser104, Ser160, Ile157, and Lys48 played significant roles in the binding interaction of these compounds as opposed to Asp53 in pyrimethamine. The four systems converged around 1.90 Å RMSD and showed more stability than pyrimethamine-bound and unbound pfDHFR. The pocket's residues across the four plasmodia were highly conserved, but Phe116 and Ile164 replaced Met in P. knowlesi and Tyr in the other species. PMD_01, PMD_02, PMD_03, and PMD_04 showed promising inhibition against pfDHFR and are, thus, potential antimalarial agents against plasmodia DHFR homologues.