Deep blue emitting dual state fluorescent triphenylamine-dicyclohexylurea derivative: Multi-stimuli responsive fluorescence switching and methanol/water sensing.

A new deep blue emissive organic fluorophore (N-cyclohexyl-N-(cyclohexylcarbamoyl)-4-(diphenylamino)benzamide (NCDPB)) was designed and synthesized, which showed strong fluorescence both in solution and solid-state. Solid-state structural analysis of NCDPB revealed non-planar twisted molecular conformation with extended hydrogen bonding between the amide functionalities. The propeller shaped triphenylamine (TPA) and non-planar cyclohexyl unit prevented close π…π stacking and produced strong deep blue emission in the solid state (λmax = 400 nm, quantum yield (Φf) = 12.6 %). NCDPB also exhibited strong solvent polarity dependent tunable emission in solution (λmax = 402-462 nm, Φf = 1.15 (compared to quinine sulphate)). NCDPB showed reversible fluorescence switching between two fluorescence states upon mechanical crushing and heating/solvent exposure. Mechanical crushing caused red shifting of fluorescence from 400 to 447 nm and heating/solvent exposure reversed the fluorescence. Further, NCDPB also displayed off-on reversible/self-reversible fluorescence switching upon exposure to trifluoracetic acid (TFA) and NH3. The repeated fluorescence switching cycles indicated high reversibility without any significant change of fluorescence intensity. The drastically different fluorescence of NCDPB in CH3OH and EtOH was utilized to distinguish them and monitor CH3OH contamination in ethanol and benzene. It showed limit of detection (LOD) of methanol up to 0.25 % and 7 % in benzene and ethanol, respectively. The water sensitive fluorescence modulation of NCDPB in organic solvents was used to sensing water contamination in common organic solvents. Thus, integration of twisted TPA with H-bonding urea produced dual state emitting organic fluorophore with multi-responsive fluorescence switching and solvent sensing.

Nano round polycrystalline adsorbent of chicken bones origin for Congo red dye adsorption.

Nano round polycrystalline adsorbent (NRPA) of chicken bones origin was utilize as effective adsorbent in Congo red dye removal via aqueous media. The NRPA adsorbent was prepared via thermal decomposition and its structure was investigated with the aids of Transmission Electron Microscopy, Fourier Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy, Energy Dispersive X-ray Analysis (EDX), and X-ray Diffractometer (XRD). A monophasic apatite phase was confirmed from XRD investigation, while functional groups analysis showed that NRPA possessed CO32-, PO43- and OH- absorption bands. The maximum adsorption capacities derived from Langmuir isotherm is 98.216 mg g-1. From the combined values of n from Freundlich and separation factor (RL) of Langmuir models, the adsorption of CR by NRPA is favourable. Thermodynamic values of 5.280 kJ mol-1 and 16.403 kJ mol-1 K-1 were found for ΔH° and ΔS° respectively. The entire values of ΔG° which ranges from - 35.248 to - 459.68 kJ mol-1 were all negative at different temperatures. Thus, nano polycrystalline adsorbent of chicken bone origin can serve as excellent adsorbent in Congo red dye removal from waste water.

Quantum chemical framework for tailoring N/B doped phenalene derivatives to achieve high performance nonlinear optical materials.

Nonlinear optical (NLO) response materials are among the smartest materials of the era and are employed to modulate the phase and frequency of the laser. The present study presents a quantum chemical framework for tailoring nitrogen/boron doped derivatives of Dihydrodibenzo [de,op]pentacene through terminal and central core modifications. The derivatives of these compounds have been designed by introducing various π-conjugated connectors as well as B/N heteroatoms in the phenalene rings. Density functional theory (DFT) methods are used to optimize the ground state molecular geometries of designed compounds, represented as 1 to 4 (phenalene derivatives) and 1-BN to 4-BN (B/N doped phenalene derivatives) at the M06-2X/6-311G* level of theory. The highest value of 116.9 × 10-24 esu and 240.2 × 10-24 esu for isotropic and anisotropic linear polarizability is shown by compound 4. Among the designed compounds, 4-BN has achieved the highest γ amplitude of 1858 × 10-36 esu owing to its unique molecular structural design. Further analysis of electronic parameters, such as electron density difference (EDD) maps, the density of states, electrostatic potentials, transition density matrix (TDM) analysis, and frontier molecular orbitals analysis (FMOs), demonstrated the more effective intramolecular charge transfer (ICT) for the best compounds, resulting in a good NLO response. The compounds were also analyzed for their potential in photovoltaic applications based on factors such as open circuit voltage values determined to be between (0.14 eV and 1.82 eV), and light harvesting efficiency (0.425-0.909).

In situ fabrication of lanthanum-doped nickel oxide nanostructures using sol-gel for the degradation of rhodamine B.

Nanoscale science represents a thriving field of research for environmental applications within materials science. This study focuses on the fabrication of pure and La-doped nickel oxide (NiO) nanostructures with varying concentrations (1.0, 2.0, 3.0, and 4.0 wt%) of lanthanum using a facile sol-gel technique. This study explores the structural, morphological, chemical composition, and optical characteristics of the resulting pure and La-doped NiO nanostructures. Techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, UV-visible spectroscopy, and photoluminescence (PL) spectroscopy were used for material analysis. The observed trend in the energy band gap (Eg) values demonstrates a continuous decrease up to a La-doping concentration of 3 wt% in NiO. However, after this concentration (at 4.0 wt%), there is a noticeable increase in the energy band gap. At lower La-doping concentrations (up to 3 wt%), the incorporation of La ions into the NiO lattice may result in the formation of defects and oxygen vacancies. The presence of these imperfections may lead to new energy levels into the band gap, resulting in partial filling and a subsequent reduction in the band gap. Beyond a specific doping concentration (e.g., 3 wt%), excess La atoms may aggregate or cluster inside the NiO lattice. This agglomeration may cause structural distortions, strain, and disturbances in the crystal lattice, resulting in an increase in the band gap. The 3 wt% La-doped NiO sample demonstrated a notable 84% degradation efficiency of the synthesized nanomaterials coupled with its inherent stability, highlighting its dual attributes of effective pollutant removal and sustained performance. Furthermore, the cyclic stability of the optimized nanostructure is anticipated to be ∼77.42% after six cycles, suggesting promising future applications in photocatalysis.

Tuning the Magnetic Behavior of Zinc Ferrite via Cobalt Substitution: A Structural Analysis.

Cobalt-doped zinc ferrite is a contemporary material with significant structural and magnetic characteristics. Our study explores the magnetic properties of cobalt-substituted zinc ferrite (ZnxCo1-xFe2O4), synthesized via a simple sol-gel method. By varying the cobalt ratio from 0 to 0.5, we found that zinc substitution impacts both the magnetization and lattice parameters. FTIR analysis suggested the presence of functional groups, particularly depicting an M-O stretching band, within octahedral and tetrahedral clusters. X-ray diffraction analysis confirmed the phase purity and cubic structure. The synthesized materials exhibited an average particle size of 24-75 nm. Scanning electron microscopy revealed the morphological properties, confirming the formation of truncated octahedral particles. In order to determine the stability, mass loss (%), and thermal behavior, a thermal analysis (thermogravimetric analysis (TGA)/differential thermal analysis (DTA)) was performed. The magnetic properties of the synthesized ferrites were confirmed via a vibrating sample magnetometer (VSM). Finally, the highest saturated magnetization and lowest coercivity values were observed with higher concentrations of the cobalt dopant substituting zinc. The synthesized nanomaterials have good stability as compared to other such materials and can be used for magnetization in the near future.

Evaluation of selected tropical marine microalgal cultures for use in biophotovoltaic platforms.

In this study, the bioelectrical power generation potential of four tropical marine microalgal strains native to Malaysia was investigated using BPV platforms. Chlorella UMACC 258 produced the highest power density (0.108 mW m-2), followed by Halamphora subtropica UMACC 370 (0.090 mW m-2), Synechococcus UMACC 371 (0.065 mW m-2) and Parachlorella UMACC 245 (0.017 mW m-2). The chlorophyll-a (chl-a) content was examined to have a linear positive relationship with the power density (p < 0.05). The photosynthetic performance of strains was studied using the pulse-amplitude modulation (PAM) fluorometer; parameters measured include the following: maximum quantum efficiency (Fv/Fm), alpha (α), maximum relative electron transport rate (rETRmax), photo-adaptive index (Ek) and non-photochemical quenching (NPQ). The Fv/Fm values of all strains, except Synechococcus UMACC 371, ranged between 0.37 and 0.50 during exponential and stationary growth phases, suggesting their general health during those periods. The low Fv/Fm value of Synechococcus UMACC 371 was possibly caused by the presence of background fluorescence from phycobilisomes or phycobiliproteins. Electrochemical studies via cyclic voltammetry (CV) suggest the presence of electrochemically active proteins on the cellular surface of strains on the carbon anode of the BPV platform, while morphological studies via field emission scanning electron microscope (FESEM) imaging verify the biocompatibility of the biofilms on the carbon anode. KEY POINTS: • Maximum power output of 0.108 mW m-2 is recorded by Chlorella UMACC 258 • There is a positive correlation between chl-a content and power output • Proven biocompatibility between biofilms and carbon anode sans exogenous mediators.

Targeting GABA receptors with chalcone derivative compounds, what is the evidence?

INTRODUCTION: In medicinal chemistry, privileged structures have been frequently exploited as a successful template for drug discovery. Common simple scaffolds like chalcone are present in a wide range of naturally occurring chemicals. Chalcone exhibits extensive biological activity and has drawn attention in this context due to its function in the GABA receptor. Epilepsy and GABA receptors are related. It is a chronic neurological condition that affects globally. AREAS COVERED: Numerous neurological disorders, including anxiety and epilepsy, have been related to GABA, the brain's most prevalent inhibitory neurotransmitter. We go through the role of GABA receptors in anxiety and epilepsy in this review. The structure-activity relationship of chalcone and its derivatives on the GABA receptor is covered in our final section. EXPERT OPINION: GABA is a potential therapeutic target for issues associated with the nervous system. We talk about the potential effects of chalcone as a treatment for epilepsy and anxiety on the GABA receptor. Therefore, thorough research is necessary in this regard; the value of in silico tools in developing and enhancing GABA agonists is significant.

Bioactivity properties of hydroxyapatite/clay nanocomposites.

The need for bioactive and non-toxic biomaterials is on a high demand in tissue engineering applications nowadays. Hydroxyapatite (HAp) is the chief constituent of teeth and bones in mammas. One of the major challenges with the use of HAp in engineering application is its brittleness and to overcome this, it's important to react it with a material that can enhanced it's fragility. To this end, HAp and HAp/clay nanocomposites were developed via wet chemical process to mimic natural HAp and to equally confer special properties such as mechanical properties, high surface area, crystallinity, high porosity, and biocompatibility on the biomaterial. The functional groups properties of the as-prepared nanocomposites analyzed by FT-IR showed that the HAp and clay posed reactive centers such as Al-Al-OH, Si-Si-OH, Si-O, PO43-, -OH, and Si-O-Al. The XRD results confirmed the formation of HAp/clay nanocomposite, while SEM and TEM images showed the morphologies of the prepared nanocomposites to be round shape particles. Besides, EDX result revealed the Ca/P ratio of HAp and HAp-C to be lower than that of stoichiometric ratio (1.67) which implies the presence of K, Na, Ca, Mg, Si and Al in the HAp/clay nanocomposite. The mechanical properties of the apatite were greatly enhanced by the addition of clay. The physiological behaviour of the fabricated apatite composites in saline solution showed steady increase in the values of the saline pH of the various biomolecules until day 5 and became fairly constant at day 7 with pH range of 7.30-7.38. Though the saline solution was acidic at the beginning due to dissolved carbon dioxide, the pH of the saline solution containing the nanocomposites gradually became neutral and fairly alkaline over time as a result of the presence of Lewis basis structures in the composites which helps in neutralizing the acidic solution. Furthermore, proliferation of apatites particles onto the surface of the nanocomposites was observed after treatment with simulated body fluids (SBF) media for 7 days. Thus, HAp/clay nanocomposites can be useful biomaterials in bone tissue engineering.

Heavy metals in five commonly consumed fish species from River Swat, Pakistan, and their implications for human health using multiple risk assessment approaches.

This study analyzed the levels of heavy metals bioaccumulation in commonly consumed riverine fish species, including G. cavia, T. macrolepis, G. gotyla, S. plagiostomus, and M. armatus from River Swat in Pakistan, and quantify their potential risk to children and adults in general and fisherfolk communities using multiple pollution and risk assessment approaches. The highest metal detected by inductive coupled plasma mass spectrometry (ICP-MS) was Zn, which ranged from 49.61 to 116.83 mg/kg, followed by Fe (19.25-101.33 mg/kg) > Mn (5.25-40.35 mg/kg) > Cr (3.05-14.59 mg/kg) > Ni (4.26-11.80 mg/kg) > Al (1.59-12.25 mg/kg) > Cu (1.24-8.59 mg/kg) > Pb (0.29-1.95 mg/kg) > Co (0.08-0.46 mg/kg) > Cd (0.01-0.29 mg/kg), demonstrating consistent fluctuation with the safe recommendations of global regulatory bodies. The average bioaccumulation factor (BAF) values in the examined fish species were high (BAF > 5000) for Pb, Zn, Mn, Cu, Cr, Ni, and Cd, bioaccumulate (1000 > BAF < 5000) for Co, and probable accumulative (BAF <1000) for Fe, and Al, while the overall ∑heavy metals pollution index (MPI) values were greater than one (MPI > 1) indicating sever heavy metals toxicity in G. cavia, followed by S. plagiostomus, M. armatus, G. gotyla, and T. macrolepis. The multivariate Pearson's correlation analysis identified the correlation coefficients between heavy metal pairs (NiCr, CuCr, PbCr, AlCo, CuNi, and PbNi), the hierarchical cluster analysis (CA) determined the origin by categorizing heavy metal accumulation into Cluster-A, Cluster-B, and Cluster-C, and the principal component analysis (PCA) discerned nearby weathering, mining, industrial, municipal, and agricultural activities as the potential sources of heavy metals bioaccumulation in riverine fish. As per human risk perspective, S.plagiostomus contributed significantly to the estimated daily intake (EDI) of heavy metals, followed by G.cavia > M.armatus > G.gotyla > T.macrolepis in dependent children and adults of the fisherfolk followed by the general population. The non-carcinogenic target hazard quotient (THQ) and hazard index (HI) values for heavy metal intake through fish exposure were < 1, while the carcinogenic risk (CR) for individual metal intake and the total carcinogenic risk (TCR) for cumulative Cr, Cd, and Pb intake were within the risk threshold of 10-6-10-4, suggesting an acceptable to high non-carcinogenic and carcinogenic risk for both children and adults in the fisherfolk, followed by the general population.

Machine learning models for efficient characterization of Schottky barrier photodiode internal parameters.

We propose ANN-based models to analyze and extract the internal parameters of a Schottky photodiode (SPD) without presenting them with any knowledge of the highly nonlinear thermionic emission (TE) expression of the device current. We train, evaluate and demonstrate the ML models on thirty-six private datasets from three previously published devices, which denote current responses under illumination and ambient temperature of graphene oxide (GO) doped p-Si Schottky barrier diodes (SBDs). The GO doping levels are 0%, 1%, 3%, 5%, and 10%. The illumination ranged from dark (0 mW/cm2) to 30 mW/cm2. The predictions are then made completely at the intensity of 60 mW/cm2. For each diode, some values of the barrier height ([Formula: see text]), ideality factor (n), and series resistance ([Formula: see text]) independently calculated using the Cheung-Cheung method were included in the training dataset. The predictions are done at unspecified intensities on the model development data at 80 and 100 mW/cm2, and on external data at 5% and 20% GO doping which were not part of the development dataset. The ANN achieved a mean square error and mean absolute error score below 0.003 across all datasets. This demonstrates the effective learning capabilities of the ANN models in accurately capturing the photo responses of the photodiodes and accurately predicting the internal parameters of the Schottky Barrier Diodes (SBDs), all without relying on an inherent understanding of the thermionic emission (TE) equation for SBDs. The ANN models achieved high accuracy in this process. The proposed ML models can significantly reduce analysis time in device development cycles and can be applied to other datasets in various fields.

Synthesis and Computational Exploration of Morpholine Bearing Halogenated Sulfonamides as Potential Tyrosinase Inhibitors.

In the presented work, a new series of three different 4-((3,5-dichloro-2-[(2/4-halobenzyl)oxy]phenyl)sulfonyl)morpholines was synthesized and the structure of these compounds were corroborated by 1 H-NMR & 13 C-NMR studies. The in vitro results established all the three compounds as potent tyrosinase inhibitors relative to the standard. The Kinetics mechanism plots established that compound 8 inhibited the enzyme non-competitively. The inhibition constants Ki calculated from Dixon plots for this compound was 0.0025 µM. Additionally, computational techniques were used to explore electronic structures of synthesized compounds. Fully optimized geometries were further docked with tyrosinase enzyme for inhibition studies. Reasonably good binding/interaction energies and intermolecular interactions were obtained. Finally, drug likeness was also predicted using the rule of five (RO5) and Chemical absorption, distribution, metabolism, excretion, and toxicity (ADMET) characteristics. It is anticipated that current experimental and computational investigations will evoke the scientific interest of the research community for the above-entitled compounds.

Investigating the potential of organic semiconductor materials by DFT and TD-DFT calculations on aNDTs.

The effects of substituting electron withdrawing and electron donating functional groups on the electronic and optical properties of angular naphthodithiophene (aNDT) were studied. Substitutions were made to the aNDT molecule at position 2 and 7, respectively. The computed ionization parameters and reorganisation energies distinguished between the p-type and n-type semiconducting natures of the unsubstituted aNDT molecule and those with the -C2H5, -OCH3, -NO2, and -CN substituents. However, the aNDT molecule with C2H5 as a substitution showed p-type behaviour since it had the largest electron reorganisation energy of about 0.37 eV. The ambipolar semiconducting property of methoxy [-OCH3-] substituted aNDT molecule was revealed from the RMSD value of 0.03 Å for both positive and negative charges with respect to neutral geometry. The absorption spectra differ significantly from those of unsubstituted aNDT, which reveals the impact of functional group substitution that changes the energy level of the molecules. The maximum absorption (λmax) and oscillator strength (f) at the excited states in vacuum was investigated using time dependent density functional theory (TD-DFT). The aNDT with electron withdrawing group [-NO2] substitution has a maximum absorption wavelength of 408 nm. Studying the intermolecular interactions between aNDT molecules was also accomplished with the help of Hirshfeld surface analysis. The current work provides insight into the development of novel organic semiconductors.

Ultrasensitive and Specific Clustered Regularly Interspaced Short Palindromic Repeats Empowered a Plasmonic Fiber Tip System for Amplification-Free Monkeypox Virus Detection and Genotyping.

The urgent necessity for highly sensitive diagnostic tools has been accentuated by the ongoing mpox (monkeypox) virus pandemic due to the complexity in identifying asymptomatic and presymptomatic carriers. Traditional polymerase chain reaction-based tests, despite their effectiveness, are hampered by limited specificity, expensive and bulky equipment, labor-intensive operations, and time-consuming procedures. In this study, we present a clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a-based diagnostic platform with a surface plasmon resonance-based fiber tip (CRISPR-SPR-FT) biosensor. The compact CRISPR-SPR-FT biosensor, with a 125 µm diameter, offers high stability and portability, enabling exceptional specificity for mpox diagnosis and precise identification of samples with a fatal mutation site (L108F) in the F8L gene. The CRISPR-SPR-FT system can analyze viral double-stranded DNA from mpox virus without amplification in under 1.5 h with a limit of detection below 5 aM in plasmids and about 59.5 copies/µL when in pseudovirus-spiked blood samples. Our CRISPR-SPR-FT biosensor thus offers fast, sensitive, portable, and accurate target nucleic acid sequence detection.

Exploring the inhibitory potential of novel piperidine-derivatives against main protease (Mpro) of SARS-CoV-2: A hybrid approach consisting of molecular docking, MD simulations and MMPBSA analysis.

In the current study, a hybrid computational approach consisting of different computational methods to explore the molecular electronic structures, bioactivity and therapeutic potential of piperidine compounds against SARS-CoV-2. The quantum chemical methods are used to study electronic structures of designed derivatives, molecular docking methods are used to see the most potential docking interactions for main protease (MPro) of SARS-CoV-2 while molecular dynamic and MMPBSA analyses are performed in bulk water solvation process to mimic real protein like aqueous environment and effectiveness of docked complexes. We designed and optimized piperidine derivatives from experimentally known precursor using quantum chemical methods. The UV-Visible, IR, molecular orbitals, molecular electrostatic plots, and global chemical reactivity descriptors are carried out which illustrate that the designed compounds are kinetically stable and reactive. The results of MD simulations and binding free energy revealed that all the complex systems possess adequate dynamic stability, and flexibility based on their RMSD, RMSF, radius of gyration, and hydrogen bond analysis. The computed net binding free energy ( Δ G b i n d ) as calculated by MMPBSA method for the complexes showed the values of -4.29 kcal.mol-1 for P1, -5.52 kcal.mol-1 for P2, -6.12 kcal.mol-1 for P3, -6.35 kcal.mol-1 for P4, -5.19 kcal.mol-1 for P5, 3.09 kcal.mol-1 for P6, -6.78 kcal.mol-1 for P7, and -6.29 kcal.mol-1 for P8.The ADMET analysis further confirmed that none of among the designed ligands violates the Lipinski rule of five (RO5). The current comprehensive investigation predicts that all our designed compounds are recommended as prospective therapeutic drugs against Mpro of SARS-CoV-2 and it provokes the scientific community to further perform their in-vitro analysis.

Nitrogen-doped carbon dots: Recent developments in its fluorescent sensor applications.

Doped carbon dots have attracted great attention from researchers across disciplines because of their unique characteristics, such as their low toxicity, physiochemical stability, photostability, and outstanding biocompatibility. Nitrogen is one of the most commonly used elements for doping because of its sizeable atomic radius, strong electronegativity, abundance, and availability of electrons. This distinguishes them from other atoms and allows them to perform distinctive roles in various applications. Here, we have reviewed the most current breakthroughs in nitrogen-doped CDs (N-CDs) for fluorescent sensor applications in the last five years. The first section of the article addresses several synthetic and sustainable ways of making N-CDs. Next, we briefly reviewed the fluorescent features of N-CDs and their sensing mechanism. Furthermore, we have thoroughly reviewed their fluorescent sensor applications as sensors for cations, anions, small molecules, enzymes, antibiotics, pathogens, explosives, and pesticides. Finally, we have discussed the N-CDs' potential future as primary research and how that may be used. We hope that this study will contribute to a better understanding of the principles of N-CDs and the sensory applications that they can serve.

Bias and illumination-dependent room temperature negative differential conductance in Ni-doped ZnO/p-Si Schottky photodiodes for quantum optics applications.

In this article, evidence for the existence of illumination and bias-dependent negative differential conductance (NDC) in Ni-doped Al/ZnO/p-Si Schottky diodes, and the possible mechanism for its origin, are presented. The atomic percentages of Ni doping were 0%, 3%, 5%, and 10%. NDC is observed between -1.5 V to -0.5 V in reverse bias under illumination, but only at certain doping levels and specific forward bias. Furthermore, the devices show excellent optoelectronic characteristics in the photoconductive and photovoltaic modes, with device open circuit voltages ranging from 0.03 V to 0.6 V under illumination.

Computational modeling of imines based anti-oxidant and anti-esterases compounds: Synthesis, single crystal and In-vitro assessment.

Molecular modeling strategy was adopted to check the biological potential of the imine based molecules against free radical, acetylcholine esterase and butyrylcholine esterase. Three Schiff based compounds as (E)-2-(((4-bromophenyl)imino)methyl)-4-methylphenol (1), (E)-2-(((3-fluorophenyl)imino)methyl)-4-methylphenol (2) and (2E,2E)-2-(2-(2-hydroxy-5-methylbenzylidene)hydrazono)-1,2-diphenylethanone (3) were synthesized with high yield. The synthesized compounds were characterized with the help of modern techniques such as UV, FTIR and NMR while exact structure was depicted with Single Crystal X-Ray diffraction technique which disclosed that compound 1 is orthorhombic, while 2 and 3 are monoclinic. A hybrid functional (B3LYP) method with general basis set of 6-31 G(d,p) were applied to optimize synthesized Schiff bases. The contribution of in-between molecular contacts within a crystalline assembly of compounds were studied using Hirshfeld surface analysis (HS). In order to check the ability of the synthesized compounds toward free radical and enzyme inhibition, in vitro models were used to assess the radical scavenging and enzyme inhibition potential which depicted that compound 3 showed highest potential (57.43 ± 1.0%; DPPH, 75.09 ± 1.0%; AChE and 64.47 ± 1.0%; BChE). The ADMET assessments suggested the drug like properties of the synthesized compounds. It was concluded from results (in vitro and in silico) that synthesized compound have ability to cure the disorder related to free radical and enzyme inhibition. Compound 3 was shown to be the most active compared to other compounds.

Synthesis, crystal structure, spectroscopic and computational investigations of the newly synthesized Schiff bases scaffold as enzyme inhibitor.

The current project was planned to access the enzyme inhibition potential of the synthesize imines; (E)-2-(2-hydroxy-4,5-dimethoxybenzylideneamino)benzonitrile 1 and (E)-2-(((3-hydroxy-4-methylphenyl)imino)methyl)-4-methoxyphenol 2 by the reported protocol of our continuous research and also assess their theoretical function in term of in silico action. The structural characterization of imines was done through advanced techniques i.e., FTIR, 1H NMR, 13C NMR, and UV spectroscopy. Moreover, a single X-Ray diffraction technique (SCXRD) was employed for real structural identification of imines dimensions, which revealed that compound 1 has a triclinic crystal system although 2 has a monoclinic one. A 2D fingerprint plot and Hirshfeld surface analysis (HS) was employed in the crystalline assembly of compounds to check intermolecular contacts and also their degree of contributions. Both compounds were optimized by B3LYP functional mode using a certain basis set (6-31G). The practical data (XRD) and theoretical data (DFT) of both molecules were compared and found between a sound coherence. Molecular docking studies in term of in silico assessment were conducted against enzymes of the esterase and alpha-glucosidase family. The docking outputs give a forecast about compounds that could be employed as protein inhibitors against analyzed protein surfaces.

A water coordinated Ni complex and a 2D Ni-MOF: topology dependent highly enhanced electrocatalytic OER activity.

Metal-organic frameworks (MOFs) with their tunable topology, functionality and coordination environment have been considered as potential materials for various applications including electrocatalysis. Herein, we have synthesised a water coordinated nickel based 2D metal-organic framework (Ni-MOF) and a coordination complex (Ni-C) and investigated their electrocatalytic OER activity. The Ni-MOF showed a 2D sheet structure with one water coordination whereas a four water molecule coordinated charged complex was formed in the Ni-C. Thermogravimetric analysis (TGA) confirmed their water coordination and good thermal stability. Interestingly, electrocatalytic OER studies showed strongly enhanced activity for the Ni-MOF and that it required a low overpotential (194 mV) to produce a geometric current density of 10 mA cm-2. The Ni-C required 225 mV to produce 10 mA cm-2. The post-catalytic analysis suggested that the Ni-MOF and Ni-C are converted to nickel hydroxides/oxyhydroxides during electrocatalysis and acted as the catalytic centre. The low Tafel slope and charge transfer resistance further supported the higher activity of Ni-MOF based nickel hydroxides/oxyhydroxides. Chronoamperometric studies revealed the excellent stability of the Ni-MOF based catalyst over 72 h. The present study revealed the potential of developing highly active electrocatalysts based on Ni-MOFs by optimizing the topology and coordination environment.

Carbazole fluorophore with an imidazole/thiazole unit: contrasting stimuli-induced fluorescence switching, water-sensing and deep-blue emission.

Carbazole-based, π-conjugated donor-acceptor fluorophores were synthesized by integrating imidazole/thiazole units. Then, we investigated the impact of subtle structural changes on fluorescence properties. Carbazole integrated with imidazole (Cz-I) and carbazole integrated with thiazole (Cz-T) showed strong fluorescence in solution (quantum yield (Φ f) = 0.18 (Cz-I) and 0.14 (Cz-T) compared with the standard quinine sulfate) and solid-state (Φ f = 8.0% (Cz-I) and 14.6% (Cz-T)). Cz-I showed relatively more blue-shifted emission in solution compared with the solid-state (λ max = 417 nm (CH3CN) and 460 nm (solid)). Cz-T exhibited deep-blue emission in the solid-state compared with solution (λ max = 455 nm (CH3CN) and 418 nm (solid)). Interestingly, Cz-T exhibited a drastic change in fluorescence in organic solvents (CH3CN, THF, CH3OH, DMSO) with a low percentage (1%) of water. Cz-I showed reversible fluorescence switching between two fluorescence states upon exposure to trifluoracetic acid (TFA)/ammonia (NH3). In contrast, Cz-T displayed reversible/self-reversible off-on fluorescence switching upon exposure to TFA or NH3. Mechanofluorochromic studies of Cz-I showed a slight reduction in fluorescence intensity upon crushing and reversal to the initial state upon heating. Cz-T exhibited off-on reversible/self-reversible fluorescence switching upon crushing/heating. Computational studies indicated that thiazole integration improved the electron-withdrawing characteristics compared with imidazole and contributed to contrasting fluorescence responses. Thus, a simple change of nitrogen with sulfur produced contrasting self-assembly in the solid-state that led to different functional properties and stimuli-induced fluorescence switching.