Synthesis of Graphene Oxide (GO) by Modified Hummer’s Method with Improved Oxidation through Ozone Treatment

Graphene Oxide (GO) is one of the common members of the graphene family owing to its unprecedented and unique properties. These properties attract researchers to use GO in several potential applications such as a transparent electrode in light-emitting diodes (LED), biosensors and solar cells, etc. In this work, GO was produced through the oxidation of graphite by potassium permanganate using modified Hummer’s method and this was followed by ozone treatment. The crystallographic structure, chemical properties, surface morphologies, and optical properties of before and after treatment of GO were determined by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and UV- visible spectroscopy. The FTIR observation confirmed the formation of GO from graphite flakes. XRD results showed peak at11.6˚ with a different interlayer spacing of 0.7nm and 0.8nm for GO and ozone-treated graphene oxide (O- GO) respectively. While for both GO and O- GO all the peaks were at the same position. Further, SEM micrographs of GO exhibited the multilayered graphene oxide with variable thickness. While the rough surface of O- GO suggests the reduction of GO particle size due to ozonation. Ultraviolet-visible spectra of GO at 223.2 nm was noted which is attributed to atomic C- C bonds but O- GO exhibited the peak shift at 232.7 nm thereby suggesting a higher surface more

Ali Dad Chandio, Asif Ahmed Shaikh, Iftikhar Ahmed Channa, Muhammad Shahzad Bacha, Jahanzeb Bhatti, Muhammad Yasir Khan and Shahid Bhutto

TDDFT-DFT Theoretical Method and Topological Analysis to the Behavior Understanding of Two Tungsten Carbonyl Complexes

We present here a study based on Density Functional Theory (DFT) calculations, to contribute to the understanding of the complexes behavior based on tungsten carbonyls ([W(C7H7NS)(CO)5], [W ( C3H6N2S)(CO)5 ] ), which consider as targets molecules of biological interest and easily detectable probes by IR spectroscopy. The results showed good agreements between the calculated and experimental values of the geometric parameters for the two complexes. A peak in the IR spectrum at 2030 cm-1 is due to the stretching of the C-O triple bond, according to the AIM analysis (0.07 <ρ <0.15 ), the existence of an intermediate interaction between the tungsten and the CO ligand. Moreover, these complexes are stable, the spectra of TD–DFT analysis showed these complexes absorb in the same domain of wavelengths, through absorption features at about 110-160 nm, characterized by natural transitions of HOMO/LUMO; of type MLCT for both complexesread more

M. A. E. Dems

Photocatalytic System using Iron-Based Catalysts: Effect of External Ions on CO2-to-CO Conversion

Herein, we report four self-assembly Iron(II/III) complex consisting triethanolamine (TEOA) as ligand and an FeIII(TPA)Cl3 (TPA= 3-(2-pyridine methyl) amine) as contrast catalyst, for photochemical reduction of CO2 to CO under visible light. The photocatalytic systems were assembled by [Ru(bpy)3]Cl2 as photosensitizer, and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo-[d]-imidazole (BIH) as electron donor. Experiments are conducted to study the relationship between CO production and the external ions. Different external counterions are provided to assist the discussion of the influence of these external ions on catalysis. Density functional theory calculations confirmed that the external ions have an effect on the CO yield. Moreover, a mechanism involving proton-coupled electron transfer is more

X-B Lu, N-X Li, T-W Jie, Q-Q Xu and Z Yang

Crystal Structure, Theoretical Analyses and Thermodynamic Properties of a Ni(II) Complex Based on ONO Donor Tridentate Acylhydrazone

A novel complex [Ni(C10H8O5N3)2]·H2O·(CH3OH) (1) (C10H9O5N3= 2-[(4-nitro- benzoyl)-hydrazone]-propionic acid) has been prepared by reaction of NiCl2 with C10H9O5N3 in mixed solvent of methanol and water. The Ni(II) complex in octahedral geometry was characterized by elemental analysis and X-ray single crystal diffraction. Isothermal titration calorimetry (ITC) was performed to observe the reactions between Ni(II) and C10H9O5N3 in methanol solvents. The results showed that the binding constant (Ka), enthalpy change (ΔH), entropy change (ΔS), and Gibbs free energy change (ΔG) of the system are 5.2×105, -11.82 kJ·mol-1, 69.78 J·mol-1·K-1 and -32.62 kJ·mol-1, respectively. In addition, the structure was optimized and frontier molecular orbital (FMO) of (1) were analyzed by B3LYP and HF methods with 6-31g more

Fengying Chen, YouYing Di and Guochun Zhang

Cholinesterase Inhibiting Terpenoid from Albizia kalkora

Albizia kalkora is potent source of phytocompounds. In recent phytochemical investigation one new triterpenoid Albizinoic acid A was isolated from the chloroform soluble fraction of medicinal plant Albizia kalkora. The structure was elucidated by physical, chemical, and spectroscopic analysis (FT-IR, 1D& 2D-NMR, Mass spectrometry). This bioactive compound exhibited inhibitory potential against Alzheimer’s disease (AD) causing enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). IC50 of Albizinoic acid A against cholinesterase were found 25.3± 0.02, AChE and 19.0±0.03, BChE while galanthamine as a positive control (0.5 ± 0.05, AChE and 8.5±0.01, BChE). This enzymes assay indicated that Albizinoic acid A has great potential of pharmacological more

Muhammad Afzal, Ejaz Ahmed, Ahsan Sharif

Identification and Pharmacological Evaluation of Syzygium cumini Derived Fixed Oils

Syzygium cumini L is an evergreen medicinal plant belonging to the family Myrtaceae, and is one of the important species of the genus Syzygium. S. cumini is traditionally used to treat various infections such as sore throat, bronchitis, dysentery, and other painful conditions. The aim of the current study was to evaluate fixed oil extracted from S. cumini for various in vitro and in vivo biological activities and identification of its fatty acids constituents. GC-MS analysis of the fixed oil revealed that the major constituents are palmitic acid methyl ester (56.45%) and stearic acid methyl ester (29.54%). Fixed oil isolated from S. cumini exhibited significant effect against Staphylococcus aureus, Shigella flexenari, and Bacillus subtilis with zone of inhibition of 28.09, 27.34, and 22.76 mm, respectively. In addition, the oil exhibited antifungal effect against Aspergillus flavus, Candida glabrata, Microsporum canis, and Fusarium solani with zone of inhibition of 80.77, 75.08, 70.98, and 65.56 mm, respectively. The oil also exerted analgesic potential at the dose of 10, 20, 40, and 60 mg/Kg with 35.44, 50.45, 65.98, and 80.34 % activity in acetic acid-induced writhing model. A mild muscle relaxant effect was noted in animal models. Taken all together, the fixed oil from S. cumini exhibits significant antimicrobial, antifungal and analgesic effects, which justifies the use of this plant in folk more

A. Rauf, T. Ahmad, H. Ahmad, I. A Khan, S.U.A. Shah, A. Ali, N. Muhammad, Y.S. Al-Awthan O. Bahattab, M.A. Al-Duais, M.S. Mubarak

Degradation of Phenol in the System TiO2 Nanoparticles and N-Containing Compound

The purpose this research was to study the decomposition of phenol in water under the influence of UV radiation in the presence of nanoparticles TiO2 and methyl-3-amicrotonate. The photochemical decomposition of phenol in the presence of UV in a system of TiO2+N containing substances was carried out. The TiO2 nanoparticles used in the reaction had a size from 10 to 30 nm and belonged to the rutile phase. Nano-TiO2 was studied by X-ray diffraction, TEM and SEM methods. All the XRD peaks were well-defined and corresponded to rutile phase TiO2. From the line broadening of the (101) diffraction peak by Scherrer’s method, the average crystal size TiO2 is about 10.3. The specific surface areas for TiO2 is 159.6 m2/g. X-ray structure analysis Fig of the studied nanocomposite materials were recorded on the Rigaku Mini Flex 600s powder diffractometer. X-ray tube with copper anode (Cu-Kα radiation, 30 kV and mA) was used to draw the diffraction specters at room temperature. At 2θ = 20°- 80° with discrete growth mode these specters were obtained as Δ2θ = 0.05° and the exposure time was τ =5 seconds. The photochemical process lasted 1 hour using a very small amount of white powder and 0.05 gr of TiO2 nanoparticles synthesized by the sol-gel method and N-containing substance. For the process 1 mgL-1of phenol solution was used. The process was monitored with a spectrophotometer “Varian Cary 50”. After the photochemical decomposition of phenol, the reaction product was analyzed on an Agilent 6980N/5975 by the method GC-MSD. The goal was to determine the percentage of photochemical decomposition of phenol in TiO2+N system and 60% decomposition of phenol was more

Sevinj Hajiyeva, Elmina Gadirova, Afsun Sujayev, Nedim Ozdemir

Cytotoxic, Thrombolytic and Antibacterial Evaluation of Synthesized Substituted and Un-Substituted Selenium-N-Heterocyclic Carbene Adducts

Alkyl-substituted azolium salts (1-8) and their Se-N-heterocyclic carbene (Se-N-Het-C) adducts (9-12) were obtained in very reasonable yields. All synthesized azolium salts and their Se-N-Het-C adducts were characterized by different spectroscopic techniques such as FT-IR, 1HNMR, 13CNMR, and elemental analysis. It was found that all synthesized Se-N-Het-C adducts were stable at room temperature in both air and moisture. In-vitro these compounds (5-12) were assessed for their antimicrobial potential against Bacillus subtilis (B. subtilis), Macrococcus brunensis (M. brunensis), and Bacillus cereus (B. cereus) in vitro. Results of MIC and inhibition zone values revealed that the majority of the Selenium N-Heterocyclic carbene adducts were active against Bacillus subtilis (B. subtilis) than Macrococcus brunensis (M. brunensis) and Bacillus cereus (B. cereus) whereas opposite in the azolium salts (5-8). Compounds 5-8 have an inhibition zone of 16±0.1-26±0.3mm against all tested bacterial strains while selenium-NHC adducts 9-12 have a zone of inhibition (16±0.2 to 25 ± 0.4mm). Adduct 12 showed good activity against all tested strains with ZI values 25 ± 0.1, 22± 0.5, 17 ± 0.3 mm and MIC values 17 ± 0.2, 16 ± 0.4 and 18 ± 0.3 µg/mL against Bacillus subtilis (B. subtilis), Macrococcus brunensis (M. brunensis) and Bacillus cereus (B. cereus) respectively. Adduct 10 showed the highest thrombolysis i-e 86.9% and adduct 12 showed good hemolysis i-e 0.51%. Overall results of thrombolysis and cytotoxicity studies revealed that the compounds are safe for preclinical studies of mouse blood in more

Amna Kamal, Muhammad Adnan Iqbal, Haq Nawaz Bhatti and Abdul Ghaffar

Direct Enantioseparation of Lorlatinib Enantiomers by Liquid Chromatography on a Chiralpak IB Column

Enantiomeric forms of many drugs are known to have different physiological and therapeutic effects. Previous studies indicated that the inhibitory activity of an enantiomer of Lorlatinib on L1196M kinase was 300 times lower than that of Lorlatinib. In this study, an analytical method for the enantioseparation of Lorlatinib was established on a Chiralpak IB column. Baseline separation was obtained within 10 min using v(n-hexane): v(2-propanol): v(diethylamine) = 85:15:0.1 as mobile phase, and a resolution higher than 2.2. Various factors of HPLC such as the effect of chiral columns, the contents of mobile phase and column temperature were thoroughly investigated. Calibration curves were plotted within the concentration range between 10 and 1000 μg mL-1 (n = 8), and recoveries between 97.86% and 100.99% were obtained, with a relative standard deviation (RSD) lower than 1.6%. The LOD and LOQ for Lorlatinib were 10.34 and 34.49 μg mL-1, respectively, and those for its enantiomer were 11.76 and 39.21 μg mL-1, respectively. Validating factors such as the accuracy, precision, linear relationship, and LOD/LOQ confirmed that the method has the advantages of high efficiency, accuracy and stability and can be used to detect the enantiomeric purity of Lorlatinib. In addition, the chiral recognition mechanisms were discussed according to the thermodynamic parameters and simulation studies between racemates and more

Mengya Liao, Xin Wang, Qin Wang and Yiwen Zhang

Assessing the Effectiveness of Saponins from Alfalfa (Medicago sativa L.) to Mitigate Cypermethrin Residues in Apples

Pesticide residues on fruits and vegetables are of major health concern around the world. Some of these pesticide residues are extremely toxic and can become a major causative factor for various diseases such as cardiovascular disorders (CVDs), lung, endocrine, and nervous system damage, as well as the circulatory system, and reproductive system problems. This study was aimed at investigating the effectiveness of saponins isolated from alfalfa (Medicago sativa L.) seeds for mitigating cypermethrin residues on apples (Malus domestica Borkh.) in comparison to tap water, citric acid, and baking soda. Cypermethrin concentration applied to apples was 1 ml/L. After washing the apples with varying concentrations of different washing solutions, analysis for cypermethrin residues was performed using a UV/VIS spectrophotometer at a wavelength of 535 nm. The maximal removal of residues recorded for baking soda, tap water, and citric acid was 92.98, 72.50, and 74.59 % respectively. Saponins exhibited a maximum of 13.90 % of residual removal which was not as effective as other washing more

Soban Manzoor, Waqas Asghar, Rao Sanaullah Khan, Nauman Khalid