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The study was conducted to explore the anticholinesterase inhibition property of eugenol derived molecules. Ten eugenol derivatives were synthesized and evaluated for the inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) by Ellman’s method. Most of the tested derivatives showed higher inhibition on BChE than AChE, however, their overall inhibitory activity was weak. In contrast, three derivatives (compounds 3,6,9) showed higher and good AChE inhibitory activity of more than 50% inhibition at 10 μg/mL. Among them, compound 9bearing a ethyl substituent at para position of the benzoyl ring showed the most potent AChE inhibition, with IC50 of 5.64 μg/mL. Ligand-protein docking simulation was also performed for the most active derived molecules (compounds 3,6,9).

A magnetic nanoparticles/reduced graphene oxide modified glassy carbon electrode (MNP/rGO/GCE) was fabricated via one-step facile synthesis route for the simultaneous determination of ascorbic acid (AA), dopamine (DA), along with uric acid (UA). A series of diseases and disorders has been associated with irregular levels of these respective analytes, thus early detection is highly crucial. Physical and electrochemical characterization of the modified electrode was conducted by using Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) analysis, X-Ray Diffraction (XRD) analysis and Brauneur-Emmet-Teller (BET), Cyclic Voltammetry (CV) and Electron Impedance Spectroscopy (EIS). The results obtained confirmed the formation of MNP/rGO composite. Differential pulse voltammetry (DPV) of MNP/rGO/GCE displays three well-defined peaks which associated to AA, DA and UA, respectively. The response towards DA is linear in the concentration range of 15 nM to 100 µM with a detection limit of 0.19 nM while a response to AA and UA is also linear in the concentration range of 10 µM to 100 µM with a limit of detection 0.22 µM and 45 nM respectively. The proposed modified electrode offers a good response towards simultaneous detection of three different electroactive species with excellent electron transfer rate, great capacitance and ideal diffusive control behavior.

Synthesis of nanoparticles by using plant have sparked interest among researchers due to environmentally safe, inexpensive and simple method to compare with chemical method. Use of plant in synthesis zinc oxide nanoparticles (ZnO NPs) that act as reducing and capping agent are more recommended, due to high production of product and rate of synthesis is faster than using microorganism. This study focus on the synthesis of ZnONPs by using leaf extract of aloe vera (Aloe bardenisis miller) with different concentration (30%, 40% and 50%) and various calcination temperature which are 500 ˚C, 700 ˚C and 900 ˚C for 4 hours. Fourier – transform infrared spectroscopy (FTIR), Thermogravimetric Analysis (TGA), scanning electron microscopy (SEM), X-ray Diffraction (XRD) and Brunauer-Emmet and Teller (BET) were used to characterize the prepared samples. FTIR spectra showed present wavenumber in between 400-500 cm-1 indicated the presence of Zn-O stretch. Powder XRD pattern confirmed the hexagonal wurtzite structure with average particles size from 24.19 nm to 67.69 nm for all concentration and temperature by using Scherer’s equation. For SEM analysis the images show irregular shape for concentrations 30% and 50% with size range from 500 nm to 900 nm while for concentration 40% cubic shape was observe with size range from 140 nm to 900 nm. All characterize show that formation of ZnO NPs depend on the concentration and calcination temperature. Sample 30% and 50% ZnO NPs was applied in lithium battery at voltage from 0.01 to 3. 1.2 mAhg-1 was recorded for sample 30% ZnO NPs while 100 mAhg-1.

Sansevieria is an ornamental plant that has many hybrids and varieties make them difficult to distinguish. The most common varieties used for medicinal purposes are Sansevieria trifasciatam which is known for cure of many diseases. However, little attention is given to this plant in proving it medicinal worth and capability as an antioxidant agent. This study was initiated to set up a metabolite classes profile and the potential enzymatic antioxidant of the variations of these plants. Crude extracts of S. trifasciata var. Laurentii and S. trifasciata var. Zeylanica were prepared from their leaves, and solvent used has different polarities. Qualitative phytochemical analysis was carried out using the extracts. Phytochemical screening suggested both of these samples contain carbohydrates in all extracts. It also show that flavonoid was found in hexane and ethyl acetate extracts while did not observed in the methanol extracts for both samples. However, alkaloid, phenol and tannin were positive in all of the methanol extracts except for hexane and ethyl acetate extracts. For the biological activity, all extracts were selected for the determination of enzymatic antioxidant activity test using catalase (CAT) assay and guaiacol peroxidase (gPOD) assay using UV-VIS spectrophotometer. Based on the results, CAT specific activity was the highest in methanol extract of S. trifasciata var. Laurentii (3.15 ± 0.50 units/mg protein) compared to S. trifasciata var. Zeylanica (2.20 ± 0.05 units/mg protein). For gPOD specific activity, ethyl acetate extract of S. trifasciata var. Laurentii shows the highest activity which is 1.46 × 10-2 ± 0.02 units/mg protein compared to the other crude extracts.

One-pot synthetic method was adopted to prepare three isomers 4-(ortho-fluorophenyl)thiosemi- carbazide), 4-(meta-fluorophenyl)thiosemicarbazide and 4-(para-fluorophenyl)thiosemicarbazide. The products were obtained in ethanolic solution from a reaction between ortho, meta and para derivatives of fluorophenyl isothiocyanate and hydrazine hydrate. This work presents the theoretical Molecular Electrostatic Potential (MEP) and Highest Occupied Molecular Orbital-Lowest Unoccupied Molecular Orbital (HOMO-LUMO) computational data through Gaussview 5.0.9 and Gaussian09 software. Experimental Cole-cole plot for conductivity determination was also illustrated. The present data is important to manipulate the properties of compounds according to the position of a fluorine atom.

The structural investigation of synthesized compounds can be carried out by various spectroscopic techniques. It is an important prospect in order to elucidate the structure of the desired products before being further utilized. The preparation of new p-nitro stilbene Schiff base derivatives as an electrochemical DNA potential spacer was synthesized using (E)-4-(4-nitrostyryl)aniline from Heck reaction with aldehydes in ethanolic solution. The data presented here in this article contains FTIR, UV-Vis and 1H and 13C NMR of (E)-4-(4-nitrostyryl)aniline and nitrostyryl aniline derivatives.

This study describes a simple green one-pot synthesis of the Palladium Nanocatalyst (PdNC) using the crude extract of a seaweed Saragassum cervicorne (S. cervicorne). The formation of PdNC was monitored by Ultraviolet-visible (UV-Vis) spectroscopy. The characteristic functional groups of phytochemicals in extract and capped PdNC surfaces were identified by FTIR analysis. The Scanning electron microscopy (SEM) analysis of the extract revealed the smooth surface area while that of the catalyst was found to be rough and irregular whereas Energy-dispersive X-ray spectroscopy (EDS) confirms the existence of Pd in the catalyst. The powder X-ray diffraction (XRD) analysis confirmed the crystalline nature of PdNC with a cubic face-centred structure. The transmission electron microscopy (TEM) was used to record the images of PdNC with a particle size of 3.131 to 16.45 nm. TGA reports reveal the degradation of the PdNC occurred at 197.8 °C. The catalytic activity PdNC was tested against the reduction of hazardous azo-dyes such as Congo red (CR), Methyl orange (MO) and Methyl red (MR) with NaBH4 as electron donor. The PdNC catalysed azo-dyes in presence of aqueous NaBH4 and was examined by UV–visible spectroscopy where PdNC mediated the electron transfer from NaBH4 to azo-dyes as a carrier. The maximum degradation was observed for Methyl Orange (0.08 mM) of about 99.66% with 60 μg/μL PdNC. Congo red (0.1 mM) showed the highest degradation of 99.25% with a catalyst loading of 40 μg/μl while that of Methyl red (0.1 mM) with 80 μg/ μL catalyst was 95.45%. The preparation of catalyst using water and exploiting water-soluble components of S. cervicorne as reducing agents makes this one-pot preparation of catalyst a novel approach for the preparation of Pd nanocatalyst. The replacement of non-toxic solvents, as well as the use of unexplored brown seaweed, is of primary importance from an economic as well as environmental perspective. Therefore, the newly prepared PdNC is a promising catalytic material obtained by the green facile synthetic method and exhibit enhanced catalytic activity in stimulation on the reduction of harmful azo dyes.

Oxidation of phenylboronic acid to phenol is one of the important industrial processes and it is generally employed in the plastic, explosive and drug manufacturing industries. Over the past decades, numerous efficient methods have been described for the generation of phenols from phenylboronic acids in the presence of oxidant. However, these methods suffered from various limitations, including the use of expensive, toxic reagents and sophisticated protocol to synthesise the phenols. Additionally, some of these reported literatures employed endangered metals, in which mankind is facing the risk of limited supply of these elements in 20 years’ time from now. As such, a viable alternative and green method for achieving organic synthesis is highly sought after by the chemists of today. Herein, we report for the first time a facile, efficient and alternative method in the preparation of phenols from phenylboronic acids using non-endangered metal as catalyst. In all cases, all phenols were afforded in satisfactory yields (81–96%) by employing column-free method. In the recyclability study, the Sm2O3 catalyst was found to possess good catalytic performance, even after being reused for five consecutive times (96–91%). In addition, SEM result revealed that the morphology of the recycled Sm2O3 catalyst was well preserved after five successive uses, which indicate no observable changes occurred in the recovered catalysts. As a final note, the current method is anticipated to be useful for industries manufacturing chemical intermediates as it provides an alternative method of catalysis by using a non-endangered metal in organic transformations.

In this study, a polypyrrole/nickel (PPy/Ni) nanocomposite has been synthesized through an in situ polymerization method. X-ray diffraction, Raman spectroscopy and Fourier transform infrared spectrometer confirm the formation of PPy in the PPy/Ni nanocomposite. From the scanning and transmission electron microscopy images, one can see that the nickel nanoparticles, which are approximately 21 nm, are encapsulated in the PPy nanofibres. Cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy are used to test the electrochemical performance of the PPy/Ni electrode. The specific capacitance of the PPy/Ni is approximately 488 F g −1 at a current density of 250 mA g −1 , which is superior to that of pure PPy (408 F g −1 ) and also demonstrates good cyclability and low charge-transfer resistance.

This study highlights on a convenient and optimised method for the preparation of nanocrystalline magnesium oxide (MgO) catalyst via sol-gel combustion method. Nanocrystalline MgO was prepared by using polyvinyl alcohol (PVA) as a complexing agent and metal nitrate (Mg (NO 3 )2.6H2O) as a precursor. The obtained MgO powder was calcined at 200 °C, 400 °C, 600 °C and 800 °C. All the MgO calcined samples including commercial MgO were characterised using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-Ray diffraction (XRD) and N2 adsorption-desorption Brunauer–Emmett–Teller (BET). From FTIR analysis, the appearance of a peak at 3700 cm-1 represent the O-H stretching bonded with Mg and the broad absorption peak at 3421 cm-1 indicates O-H stretching band which is due to the absorption of moisture from the surrounding. (BET) results indicate the MgO sample that has been calcined at 400 °C shows the largest surface area. SEM images show there is porosity in all MgO powder. While XRD patterns revealed that higher temperature of calcination gives higher crystallinity of the MgO samples.

Electrochemical DNA sensor (E-DNA) have received attention in numerous application due to its high sensitivity, low cost, rapid response, simple, portability, and easy to operate. The objective of this study was to synthesis three Schiff bases derived from 4-amino-4'-nitrostilbene and 4-alkoxybenzaldehyde derivatives to be use as a potential linker in E-DNA. Schiff bases reaction are form from condensation reaction between primary amine and aldehyde at 79 °C using ethanol as solvent. All compounds are investigated and discussed by Fourier transform-infrared spectrometer (FTIR), UV-Vis spectrophotometer and Nuclear Magnetic Resonance (NMR). FTIR showed formation of C=N (imine) stretching vibrations at range 1604 cm-1 to 1608 cm-1. In UV-vis, absorbance of C=N (imine) group can be observed at peak range 385 nm to 388 nm. While in the 1H NMR the peak of CH=N (Imine) group was found at δH 8.34 ppm and 13C NMR for three Schiff bases were discovered at δC 158.80, 158.79 and 158.78 ppm.

The nature of functional proteins adsorbed on solid surfaces is interesting from the perspective of developing of bioelectronics and biomaterials. Here we present evidence that citrine (one of yellow fluorescent protein variants) adsorbed on modified gold surfaces would not undergo denaturation and energy transfer among the adsorbed citrine molecules would occur. Gold substrates were chemically modified with 3-mercaptopropionic acid and tert-butyl mercaptan for the preparation of hydrophilic and hydrophobic surfaces, respectively. A pure solution of citrine was dropped and dried on the modified gold substrates and their surface morphology was studied with scanning tunnelling microscopy (STM). The obtained STM images showed multilayers of citrine adsorbed on the modified surfaces. On hydrophobic surfaces, citrine was adsorbed more randomly, formed various non-uniform aggregates, while on hydrophilic surfaces, citrine appeared more aligned and isolated uniform protein clusters were observed. Fluorescence lifetime and anisotropy decay of these dried citrine layers were also measured using the time correlated single photon counting method. Fluorescence anisotropy of citrine on the hydrophobic surface decayed faster than citrine on the hydrophilic surface. From these results we concluded that fluorescence energy migration occurred faster among citrine molecules which were randomly adsorbed on the hydrophobic surface to compare with the hydrophilic surface.

This is a preliminary study of alkoxy substituted Heck-schiff base compound as recognition layer in electrochemical DNA sensor for liver cancer. 4-(4-nitrostyryl)aniline was synthesized by bis (triphenylphosphine) palladium (II) dichloride as catalyst and has been characterized by using Fourier transform-infrared spectrometer (FTIR), UV-Vis spectrophotometer and Nuclear Magnetic Resonance (NMR) spectra. The result obtained from FTIR show that there are formation of N=O (NO2) asymmetric stretching vibrations 1340 cm-1. In UV-vis, absorbance of NO2 can be observed at peak 410 nm. While in the 1H NMR and 13C NMR the peak of C-C coupling was found in the range of δH 6.84-7.09 ppm and δC 125.23 ppm.

Methyl 4-(4-aminostyryl) benzoate was successfully prepared and characterized. The compound was characterized via Fourier transform infrared (FT-IR), 1H and 13C nuclear magnetic resonance (NMR) and UV-Visible analysis (UV-Vis). From the FT-IR result, it can be concluded that there is absorption of interest in carbon-carbon bond formation at 1624 cm−1 and it is assigned as C=C. While 1H NMR result showed the presence of methoxy resonance as singlet and the resonance of carbon-carbon bond formation at the expected regions. 13C showed the most deshielded regions appeared at carbons of carbonyl which is at δC 166.01 ppm and the carbons for methyl group at 50.97 ppm. In UV-Vis analysis, there are two important peaks that can be observed which is attributed in the presence of n-π* and π-π* electronic transition of C=O chromophores. The result suggested that the synthesized compound has great potential to act as precursor for formation of Schiff base derivatives. However, this study is still under preliminary st...

This research studied the synthesis of graphite oxide and reduced graphite oxide via a low- cost manufacturing method. The process started with the chemical oxidation of commercial graphite powder into graphite oxide by Staudenmaier's method, followed by the chemical reduction of graphite oxide in ammonium hydroxide vapor. Subsequently, graphite oxide and reduced graphite oxide were assembled into a thin film, and microscale liquid droplets were placed into the film surface for measurement of wettability and contact angle. It is found that a graphite oxide sheet is hydrophilic while a reduced graphite oxide is hydrophobic with a contact angle equal to 120°C and 53°C respectively.

This research aim to synthesis and characterize several p-cyano stilbene Schiff base molecules as a potential linker in electrochemical DNA sensor. Schiff base reaction is form from condensation reaction between primary amine and aldehyde at 79 °C using ethanol as solvent. All compounds are investigated and discussed by Fourier transform-infrared spectrometer (FTIR) and Uv-vis spectrophotometer. For computational study, structure drawings were constructed using GaussView 5.0. Geometry optimization has been carried out using density functional theory (DFT) at bB3LYP/6 31G and performed using Gaussian09 software. FTIR showed formation of C≡N stretching vibrations at 2224 cm-1 also another important stretching at 1604 cm-1 and 1249 cm-1 which represent C=N and C-O mode respectively. In UV-vis, absorbance of C=N (imine) group can be observed at peak range 363 nm and transition of aromatic C=C can be seen at 238 nm. Theoretical and experimental results obtained are comparable and p-cyano stilbene Schiff base compounds were successfully synthesised and can be further applied as a linker in E-DNA sensor.