001403   DEVI C L, NARAYANAN S S (Analytical Chemistry Dep, Madras Univ, Chennai - 600 025, Email: sriman55@gmail.com) : Poly(amido amine) dendrimer and silver nanoparticle–multi-walled carbon nanotubes composite with poly(neutral red)-modified electrode for the determination of ascorbic acid. Bull Mater Sci 2019, 42(2), 73.

A new film containing poly(amido amine) dendrimer, silver nanoparticles and multi-walled carbon nanotubes composite with poly(neutral red) was prepared on a paraffin wax impregnated graphite electrode. The PAMAM/AgNPs– MWCNT/PNR film exhibited promising electrocatalytic oxidation of ascorbic acid (AA) in acetate buffer solution of pH 4.0. The PAMAM/AgNPs–MWCNT/PNR film-modified electrode enhanced the sensitivity of detection of AA. The PAMAM/AgNPs–MWCNT/PNR film-modified electrode was characterized by cyclic voltammetry, chronoamperometry, hydrodynamic voltammetry (HDV) and difference pulse voltammetry. These experiments confirmed the electrocatalytic oxidation of AA by PAMAM/AgNPs–MWCNT/PNR film-modified electrode. The PAMAM/AgNPs–MWCNT/PNR modified electrode has been found to possess good electrocatalytic activity towards AA oxidation which has been observed at a lower oxidation potential of around 0.26 V with a higher current response. The electrochemical oxidation of AA by PAMAM/AgNPs–MWCNT/PNR-modified electrode involved a two proton and two electron process. A linear relationship between the catalytic current and AA concentration was obtained in the range from 0.16 to 2500 µM with a detection limit of 0.053 µM.

10 illus, 2 tables, 36 ref

001400   DANG L H, HUYNH N T, PHAM N O, NGUYEN C T, VU M T, DINH V T, LE V T, TRAN N Q (Graduate Univ of Science and Technology, Ho Chi Minh City 700000, Vietnam, Email: tnquyen@iams.vast.vn) : Injectable nanocurcumin-dispersed gelatin–pluronic nanocomposite hydrogel platform for burn wound treatment. Bull Mater Sci 2019, 42(2), 71.

To utilize the potent pharmaceutical properties of curcumin (Cur) and gelatin-based materials in tissue regeneration, we fabricated a thermosensitive nanocomposite hydrogel based on pluronic-grafted gelatin (PG) and nanocurcumin (nCur) to enhance burn healing. In this method, the amphiphilic PG played a role as a surfactant to prepare and protect nanosized Cur particles, which could overcome the poor dissolution of the phytochemical. The synthesized PG was identified by ¹H nuclear magnetic resonance. Depending on the amount of Cur, size distribution of the dispersed nCur ranged from 1.5 ± 0.5 to 16 ± 3.2 nm as observed using transmission electron microscopy and dynamic light scattering. The nCur-dispersed PG solution formed nCur–PG nanocomposite hydrogel on warming up to 35^◦C. Release profile indicated sustainable release of Cur from the injectable platform. Fibroblast cells were well proliferated on the nanocomposite hydrogel. The nCur–PG enhanced the healing process of second-degree burn wound. These results showed potential applications of the biomaterial in tissue regeneration.

10 illus, 36 ref

001485   VINH H X, THANG N C, TIEN D P T, HUY B T (Chemistry Dep, Changwon National Univ, Changwon 51140, Korea, Email: buithehuy.nt@gmail.com) : Structure and luminescence properties of K₂GdF₅:Tb³⁺ synthesized by solid-state reaction method. Bull Mater Sci 2019, 42(2), 70.

K₂GdF₅:Tb³⁺ material used in dosimetry field was synthesized by solid-state reaction method. The scanning electron microscopy image showed that the material exhibits porous surface with a very large surface area. The photoluminescence spectrum confirmed energy transfer process from Gd³⁺ ions to Tb³⁺ ions, and the luminescence of this material was entirely due to Tb ions. The high luminescent intensity at 542 nm was perfectly consistent with the sensitive wavelength range of photomultiplier tubes in the thermoluminescence (TL) reader. The TL-glow curve was very simple with the temperatures of the main peak in the range from 200 to 230^◦C, and the glow-curve shape was suitable for dosimetry purposes. The TL intensities of K₂GdF₅:10 mol % Tb³⁺ was higher than that of common CaSO₄:Dy³⁺ dosimeters. The estimation on available application of the prepared material in neutron dose measurement was carried out.

10 illus, 24 ref

001456   RAI U S, SINGH M, RAI R N (Chemistry Dep, Banaras Hindu Univ, Varanasi - 221 005, Email: usrai_bhu@yahoo.co.in) : Green synthesis, characterization and optical properties of eutectics and 1:1 intermolecular compounds: N,N-dimethylaminobenzaldehyde–anthranilic acid and 2-(4-(dimethylamino)benzylideneamino)benzoic acid– p-nitroaniline systems. Bull Mater Sci 2019, 42(2), 67.

Phase diagrams of N,N-dimethylaminobenzaldehyde (DMAB)–anthranilic acid (AA) and 2-(4- (dimethylamino)benzylideneamino)benzoic acid (DMABAB)–p-nitroaniline (PNA) systems, determined by the thaw-melt method, give two eutectics and a 1:1 intermolecular compound (IMC) in each case. Appropriate amounts (10 g) of each of the eutectics and the IMCs were prepared by a green synthetic method involving a solid state reaction without any solvent. These materials were characterized by X-ray diffraction, thermal and spectral methods and the optical properties of the pure components and the IMCs were studied. While negative values of heat of mixing in the case of a DMAB–AA system suggest clustering of molecules in both eutectic melts, those of positive value in E₁ and negative value in E₂ of the DMABAB–PNA system indicate the formation of a quasi-eutectic structure in E₁ melt and clustering of molecules in E₂ melt. The IMC of DMAB–AA system shows strong dual emission with two λ_max one at 380 nm and the second at 450 nm with a total quantum efficiency of 0.49. The IMC of DMABAB–PNA system also shows a similar observation with two λ_max one at 390 nm and second at 435 nm with a total quantum efficiency of 0.31.

8 illus, 2 tables, 29 ref

001429   KAUR B, CHAND S, SINGH K, MALIK A K (Chemistry Dep, Punjabi Univ, Punjab - 147 002, Email: balwindertahem1987@gmail.com) : Detoxification of dye contaminated water by Mn²⁺-doped ZnS nanostructures. Bull Mater Sci 2019, 42(2), 61.

Chemical co-precipitation route was successfully employed to synthesize polyethylene glycol-coated pure and doped Zn_1−xMn_xS (0 ≤ x ≤ 0.1) nanoparticles. The crystallographic and morphological analyses have been done by X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The formation of cubic crystal structure and quasi-spherical morphology has been revealed by XRD and TEM, respectively. The optical analyses have been done by UV– Vis absorption spectroscopy and energy resolved photoluminescence spectroscopy. Energy dispersive X-ray spectroscopy study has been carried to analyse the elemental composition. The doping concentration dependent photo-catalytic activity was checked to analyse the photo-catalytic potential of Zn_1−xMn_xS nanoparticles under UV irradiation.

9 illus, 22 ref

001384   ADEKOLA F A, OLOSHO A I, ADELEKE A A, ELETTA O A A, AGAJA S B (Industrial Chemistry Dep, Ilorin Univ, Ilorin 240003, Nigeria, Email: adebayoolosho@gmail.com) : Physico-mechanical assessment of plaster of Paris bandage produced from locally sourced materials. Bull Mater Sci 2019, 42(2), 59.

Despite the abundance of gypsum and other materials needed for the production of plaster of Paris (POP) in the country, Nigeria relies heavily on the importation of orthopaedic POP bandage. Therefore, the present study aimed at producing POP bandage (LPOP) from locally sourced pure gypsum and cassava starch. Physico-chemical parameters, such as amylose content, amylopectin content, water absorption capacity (WAC), swelling capacity (SC) and browning–charring temperature (BCT) were obtained for the starch binder. A slurry of pure gypsum powder and 2 % gelatinized starch binder was impregnated on cotton gauze and cured in an oven at 180^◦C for an hour to produce the LPOP. A comparative mechanical test was carried out on the LPOP and a POP bandage (CPOP) acquired from the market using a universal testing machine. The results showed that starch contains 9.06 mg per 100 g amylose and 24.1 mg per 100 g amylopectin which implied that it has a good binding property. The SC, WAC and BCT were evaluated to be 69.79, 81.94 and 190^◦C, respectively. The yielding tensile force for LPOP and CPOP are 148 and 460 N, respectively. The horizontal compressive strength of the LPOP and CPOP are 1712 and 1595 N while the vertical compressive strengths are 1070 and 623 N, respectively. These results show that the LPOP produced from locally sourced materials compete favourably in terms of mechanical properties with POP bandage in the market. Thus, based on its strength, it is recommended for orthopaedic casting.

5 illus, 4 tables, 34 ref

001415   HAMSAN M H, SHUKUR M F, AZIZ S B, KADIR M F Z (Malaya Univ, Kuala Lumpur 50603, Malaysia, Email: mfzkadir@um.edu.my) : Dextran from Leuconostoc mesenteroides-doped ammonium salt-based green polymer electrolyte. Bull Mater Sci 2019, 42(2), 57.

Biopolymer electrolytes based on dextran from Leuconostoc mesenteroides doped with ammonium nitrate (NH₄NO₃) are synthesized via a solution cast method. Fourier transform infrared analysis is used to determine the complexation between cation from the salt with functional groups of dextran. The ionic conductivity of undoped dextran film at room temperature is identified as (8.24 ± 0.31) × 10⁻¹¹ S cm⁻¹. A conductivity of (3.00 ± 1.60) × 10⁻⁵ S cm⁻¹ is achieved with the inclusion of 20 wt % NH₄NO₃ to the pure dextran film. The conductivity at a high temperature of the electrolyte obeys Arrhenius theory. Field emission scanning electron microscopy results show that the highest conducting sample has a porous surface. Results from the dielectric study show a non-Debye characteristic.

10 illus, 2 tables, 51 ref

001468   SOLAK E K, ASMAN G, MUHAMMET S M (Chemistry and Chemical Engineering Technologies Dep, Ostim, Gazi Univ, Ankara 06374, Turkey, Email: ebrukondolot@gazi.edu.tr) : Controlled release of huperzine-A from biocompatible copolymer microspheres. Bull Mater Sci 2019, 42(2), 55.

Huperzine-A (Hup-A) is a reversible acetylcholinesterase inhibitor used for patients suffering from Alzheimer’s disease. Hup-A has to be administered daily because of its short half-life time and narrow therapeutic range, making it less suitable for clinical use. In the present study, we studied its controlled drug delivery using biodegradable microspheres to avoid frequent dosing. Hup-A-loaded microspheres were prepared by an emulsion crosslinking method using a mixture of water and oil. Calcium chloride was used as a crosslinker. Primarily, we prepared sodium alginate (NaAlg) microspheres and investigated the in vitro release. The in vitro release studies were carried out successively at three different pH (1.2, 6.8 and 7.4) values for 2 h. To increase the durability of the NaAlg microspheres, NaAlg was blended with acrylamide (AAm)-grafted poly(vinyl alcohol) (PVA). It was determined that the presence of the PVA-g-AAm increased the physical resistance of the microspheres and also increased the amount of Hup-A loading and release. Additionally, the effect of the NaAlg/PVA-g-AAm (w/w) blend ratio, drug/polymer (w/w) ratio, crosslinker concentration and crosslinking period on the release of Hup-A was investigated. The prepared microspheres were characterized using Fourier transform infrared spectroscopy, differential scanning calorimetry and scanning electron microscopy.

7 illus, 2 tables, 37 ref

001457   RIVERA M, RIVERA J M, AMELINES-SARRIA O, MARTÍNEZ-GARCÍA M (Nacional Autónoma de México Univ, 04510 Mexico) : Evaporated porphyrin films as nitrogen dioxide gas sensors. Bull Mater Sci 2019, 42(2), 50.

In this work, metal-free and copper(II) 5,10,15,20-tetrakis(-4-(methyl 2-phenoxyacetate)) porphyrin films were employed as nitrogen dioxide gas sensors. The films were vacuum evaporated and the sensor response was evaluated as changes in the optical absorption spectra, hydrophobic properties and conductivity at different gas concentrations. The morphology of the films obtained with scanning electron and atomic force microscopy before and after gas exposure indicated different interaction mechanisms. For instance, metal-free film exhibited an absorption phenomenon due to gas diffusion towards the bulk film because of the presence of pores at the film interface, while the copper-porphyrin film showed interfacial film degradation. From UV–vis results, differences in the gas content within the film were detected due to the formation of new peaks around 680 nm in agreement with morphological findings. Contact angle results exhibited less hydrophobic films after gas adsorption as a result of changes in the surface roughness. In addition, the conductivity values were not only dependent on the gas concentration but also on the molecular structure. For instance, gas absorption within the metal-free films truncated electron mobility paths decreasing the conductivity response in comparison with the copper system. Finally, the molecular packing arrangement and gas absorption were also investigated by using density functional theory, which provided some insights into the molecular-gas interactions and supported experimental results.

8 illus, 15 ref

001432   LEE D-J, JIN F-L, PARK S-J (Chemistry Dep, Inha Univ, Nam-Gu, Incheon 402-751, Republic of Korea) : Preparation of Cu nanoparticles by a pulsed wire evaporation process for conductive ink applications. Bull Mater Sci 2019, 42(2), 49.

In the present study, Cu colloidal nanoparticles and nanopowders were successfully synthesized by a pulsed wire evaporation process. Cu-based nano-inks were prepared by mixing Cu nanoparticles with acrylic resin and solvent. Cu nanoparticles with a particle size of <20 nm were uniformly dispersed in ethylene glycol. The Cu nanopowders were successfully coated with an organic solvent composed of a hydrocarbon compound. This organic coating effectively inhibited the oxidation of Cu nanopowders. In addition, the stability of dispersion of Cu nanoparticles in the inks was improved by a ball-milling process. The electrical conductivity of the prepared Cu nano-inks was 10–28 µS cm⁻¹ for 20–40 wt % of Cu.

10 illus, 1 table, 36 ref

001481   TONG S (Southwest Petroleum Univ, Chengdu 610500, Sichuan, People’s Republic of China, Email: tongshihong@126.com) : Effects of doping Pr³⁺ and Gd³⁺ into YAG:Ce phosphors on the luminescence properties. Bull Mater Sci 2019, 42(2), 48.

A series of (Y_0.98−x−yCe_0.02Pr_xGd_y)₃Al₅O₁₂ (x = 0−0.02, y = 0, 0.3) phosphors were prepared by a modified co-precipitation method. The phases, luminescence properties, effect of calcination temperature on luminescence properties and energy transfer (ET) were investigated. The results indicated that the doping of Pr³⁺ and Gd³⁺ in all samples did not produce any new phases but caused a slight lattice expansion. The series of (Y_0.98−xCe_0.02Pr_x )₃Al₅O₁₂ phosphors emit additional red light at 612 nm, and when x = 0.005, the red/yellow ratio of the emission spectrum is the largest. Compared with the (Y_0.975Ce_0.02Pr_0.005)₃Al₅O₁₂ phosphor, continued doping 30 at % Gd³⁺ in the (Y_0.675Ce_0.02Pr_0.005Gd_0.3)₃Al₅O₁₂ sample makes the peak wavelength of yellow light emission shift from 533 to 561 nm. Doping Pr³⁺ and Gd³⁺ results in the decrease of integrated emission intensity, but the emission intensity and the red/yellow ratio can be increased by raising the calcination temperature. In addition, there is only the ET from Ce³+ to Pr³⁺ in the (Y_0.675Ce_0.02Pr_0.005Gd_0.3)₃Al₅O₁₂ sample.

7 illus, 18 ref

001396   BOZGEYIK M S (Metallurgy and Ceramics Science Dep, Tokyo Institute of Technology, Tokyo 152-8550, Japan) : Investigating structural features of Ba and Zr co-substituted strontium bismuth tantalate thin films. Bull Mater Sci 2019, 42(2), 47.

Structural (crystal and microstructure), chemical and electronic states, and ferroelectric and electrical features of Ba and Zr co-substituted strontium bismuth tantalate (SBT) were probed in this study. Distinctly, Ba and Zr were substituted for Ta and Sr sites of Sr_0.8Bi_2.2Ta₂O₉ in the form of Sr_0.8−xBa_xBi_2.2Ta_2−yZr_yO₉. To investigate the impact of the co-substitution on the crystal structure, microstructure, ferroelectric and electrical properties, Sr_0.8−xBa_xBi_2.2Ta_2−yZr_yO₉ thin films were deposited on Pt/Ti/SiO₂/Si(100) wafers by sol–gel spin by coating method. Crystal structure, microstructure, chemical and electronic states, ferroelectric, capacitance and leakage current characteristics of the films were studied to investigate potential for one transistor type ferroelectric random access memories (1T-type FeRAMs). Successful substitutions up to 10 mol % lead to reduction of double remanent polarization (2P_r) to 10.26 µC cm⁻², and dielectric constant (ε_r) to 135. These values demonstrate that successful co-substitution of limited Ba and Zr in SBT with stable crystal structure has the ability to decrease P_r and ε_r values of the ferroelectric material which can be a candidate gate to be utilized in ferroelectric field-effect transistors (FeFETs) for 1T-type FeRAM applications.

8 illus, 2 tables, 24 ref

001447   NOORI S M (Tehran Univ, Tehran, Iran) : Synthesis and characterization of Ni–Si₃N₄ nanocomposite coatings fabricated by pulse electrodeposition. Bull Mater Sci 2019, 42(2), 44.

Pure Ni and Ni–silicon nitride (Si₃N₄) nanocomposite coatings have been successfully fabricated on copper substrates by a pulse electrodeposition method employing the Watts bath. The obtained coatings were characterized with X-ray diffractometry and scanning electron microscopy. Also, surface hardness and the corrosion behaviour of the coatings were analysed by potentiodynamic polarization and electrochemical impedance spectroscopy in a 3.5 % NaCl solution. It was found that incorporation of Si₃N₄ particulates has reduced the crystallite size and also changed the growth orientation of the crystallite from (111) to (220) and (200) crystal planes. The co-deposition of Si₃N₄ in the Ni matrix led to better properties of these coatings. Accordingly, the hardness value of nanocomposite coatings was about 80–140 Hv higher than that of pure nickel due to dispersion-strengthening and matrix grain refining and increased with the enhancement of incorporating Si₃N₄ particle content. The presence of the Si₃N₄ particulates slightly decreases the current efficiency. The current efficiency was decreased by increasing current density from 1 to 4 A dm⁻². Moreover, the corrosion resistance of nanocomposite coatings was significantly higher than the pure Ni deposit. Also, the Ni–Si₃N₄ coating produced at a density of 4 A dm⁻² showed the lowest corrosion rate (0.05 mpy).

9 illus, 6 tables, 30 ref

001413   GHOSH R, SUDHA V, HARINIPRIYA S (SRM Institute of Science and Technology, Kattankulathur - 603 203) : Thermodynamic analysis of electrodeposition of copper from copper sulphate. Bull Mater Sci 2019, 42(2), 43.

The free energy of activation of copper electrodeposition from copper sulphate solution is derived in terms of the dehydration energy of copper sulphate, hydration number of copper sulphate, solvated work function of the host metal and coordination number of the host metal on which the copper deposition is carried out. The free energy of activation for copper electrodeposition on 31 different host metals had been evaluated. The trend in the free energy of activation on different metals is studied and feasible electrodeposition of copper for appropriate applications had been suggested. The methodology is extended to obtain the exchange current densities for copper electrodeposition on different surfaces of Pt in acid medium and compared with the existing literature.

6 illus, 2 tables, 45 ref

001406   DHOBLE L R, ITANKAR P R, PRASAD S K (Pharmaceutical Sciences Dep, Nagpur Univ, Nagpur, Maharashtra) : Formulation, development and evaluation of sennoside enriched Senna extract tablets of different concentrations. J Pharmacogn Phytochem 2019, 8(2), 2043-8.

Senna, a plant of ethnopharmacological importance has been traditionally used in the treatment of chronic constipation. Ancient texts from Ayurveda have mentioned the potency of Senna as a laxative. The traditional methods incorporated for formulation of Senna for the treatment of constipation, suffer from inherent drawbacks like compound-specific isolation and extraction, lack of standardisation, safety and efficacy standards and non availability in modern dosage forms. Therefore, it was proposed to prepare uncoated oral dosage form tablets of optimized and enriched extracts from dried Senna leaves. It was also envisaged to standardize the product making it acceptable for the modern generation of end users. Maceration process was used for extraction of dried Senna leaves. The physicochemical and preliminary phytochemical screening studies were performed. Hydroalcoholic extracts were prepared in concentrations of 50 %, 70 %, 80 % and 100 % ethanol. Enrichment of the Senna extracts was done using Borntrager’s process. It was observed that 70 % ethanol enriched Senna extract resulted in higher yield value as compared to the other extracts. The presence of Sennosides was asserted using TLC coupled UV analysis. In HPLC analysis, Sennoside B was used as the marker compound, wherein 70 % ethanol enriched extract showed relatively higher concentration of Sennosides. Senna enriched and optimized extract tablets were prepared by using wet granulation method. Evaluation parameters of Senna tablets were found to be within the Pharmacopoeial limits. During dissolution studies, it was found that 70 % enriched ethanolic extract of Senna resulted in higher % cumulative release of tablet ingredients at 90 minute time interval. Hence, 70 % enriched Senna extract can be considered as the optimum concentration in terms of extraction, analysis, concentration of total Sennosides, formulation and evaluation, so as to achieve the desired therapeutic and pharmacological benefits of the product.

5 illus, 6 tables, 40 ref

001469   SOWBARANIGA R, CHITRA M (Botany Dep, Government Arts Coll, Coimbatore, Tamil Nadu) : Phytocompounds identification in Cucumis dipsaceus Ehrenb ex. Spach fruits by gas chromatography-mass spectrometry (GC-MS) analysis. J Pharmacogn Phytochem 2019, 8(2), 1453-8.

Phytochemicals identification is necessary to explore its usefulness towards medicinal value and commercial products preparation. Cucumis dipsaceus Ehrenb ex. Spach is a less explored plant in India and the present study focused to find out the phytochemicals present in its fruits by Gas Chromatography –Mass Spectrometry analysis. Fruit extracts were prepared using Petroleum ether, Acetone, Ethanol and Water solvents by successive soxhlet extraction. Crude extracts were subjected to GC-MS analysis and the spectra of the obtained components were compared with the GC-MS NIST (2008) library. The results revealed the presence of bioactive compounds, Octadecanoic acid, Pentadecanoic acid, Eicosanic acid, Oleic acid, Tetradecanal, octadecanal, Pentadecanal, Tridecanoic acid, alkyne and amide compounds. Thus, the present study explored the presence of bioactive compounds in fruits of Cucumis dipsaceus.

4 illus, 1 table, 22 ref

001488   YADAV M, KUSHAWAHA D K, CHATTERJI S, MAURYA G S, RAI A K, WATAL G (Chemistry Dep, Allahabad Univ, Prayagraj, Uttar Pradesh) : Inhibitory effect of C. esculenta on α-Amylase and α-glucosidase enzyme activity: A LIBS based study. J Pharmacogn Phytochem 2019, 8(2), 1402-6.

The present study deals with the evaluation of inhibitory activity of Coloasia esculenta for α-amylase and α-glucosidase enzymes. Correlation of activity with LIBS based phytoelemental profile of C. esculenta is uniqueness of the study. Varied concentrations ranging from 1 to 10 mg/ml of aqueous extract of C. esculenta were screened for their α-amylase and α-glucosidase inhibitory activities in vitro. Appreciable α-glucosidase and α-amylase inhibitory efficacies were observed in a concentration dependent manner. C. esculenta showed maximum α-glucosidase and α-amylase inhibition of 56.92 and 73.85 % at 10 mg/ml concentration with IC₅₀ value at 6.05 and 6.19 mg/ml respectively. However, standard drug, acarbose showed maximum α-glucosidase and α-amylase inhibition of 95.52 and 98.17 % at 1 mg/ml concentration with IC₅₀ value at 1.83 and 0.25 mg/ml respectively. LIBS analysis reveals the presence of phytoelements viz. Mg, Ca, K and Na which are well known antidiabetic elements and hence could be responsible for inhibitory activities of both the carbohydrate hydrolyzing enzymes. Thus, it could be stated that, the plausible mechanism for antidiabetic efficacy of C. esculenta in vivo, could be due to its α-glucosidase and α-amylase enzyme inhibition activity and as such it can be explored as a potential candidate for the management of diabetes.

4 illus, 2 tables, 26 ref

001487   WANI A A, JAN I, DAR A A, MUBASHIR S, SOFI K A, SOFI J A, DAR I H (Sher-e-Kashmir Univ of Agricultural Sciences and Technology (SKUAST-K), Srinagar, Jammu and Kashmir) : Dissipation behaviour, quantification and risk assessment of chlorpyrifos in green pea by gas chromatograph. J Pharmacogn Phytochem 2019, 8(2), 1357-62.

The present study was conducted to evaluate the persistence, half-life, dissipation behaviour and risk assessment of Chlorpyrifos on green pea by gas chromatography-electron capture detector. Chlorpyrifos 20 EC at 300g.a.i.ha^-1 was applied during fruiting stage followed by another application at 10 day interval. The samples were extracted by using quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. Herein we report a modified accurate and cost-effective gas chromatography method for the determination of average deposits of Chlorpyrifos on green pea. The initial deposits were found to be 1.37 mg kg^-1 and reached below limit of determination after 15 days at recommended dosage with half-life period of 1.77 days. For risk assessment studies, a waiting period of 15 days at the recommended dosages is suggested safe for the consumption of green pea. The developed method is simple, sensitive, selective and repeatable and can be extended for Chlorpyrifos based standardisation of herbal formulations containing green pea and its use in pesticide industries.

5 illus, 3 tables, 22 ref

001438   MEHRA N, JAIN N K (Devi Ahilya Vishwavidyalaya Indore, Indore, Madhya Pradesh) : Comparative phytochemical screening of Curcuma angustifolia, Curcuma decipiens and Curcuma longa by using GC-MS. J Pharmacogn Phytochem 2019, 8(2), 1227-34.

Present research was constructed to find out the phytochemical compounds of methanol, ethanol and acetone extracts of Curcuma longa, Curcuma angustifolia and Curcuma decipiens. This investigation also revels the comparision of methanolic extract of these selected species of family zingiberaceae by gas chromatography and mass spectrometry technique. The main goal of this study to compare phytochemicals of cultivated species with wild species of genus Curcuma. The results obtained from GCMS indicate that 34 phytochemicals were found in Curcuma angustifolia, 63 phytochemicals were found in Curcuma decipiens and 53 phytochemicals were found in Curcuma longa. 10 phytochemical compounds of Curcuma longa were identical with Curcuma angustifolia and 14 with Curcuma decipiens, while other phytochemicals of these wild species were different from Curcuma longa and can be used to treat various diseases.

5 tables, 20 ref

001385   AFRIN N S, HOSSAIN M A, SAHA K (Chemistry Dep, Jahangirnagar Univ, Dhaka-1342, Bangladesh) : Phytochemical screening of plant extracts and GC-MS analysis of n-Hexane soluble part of crude chloroform extract of Cuscuta reflexa (Roxb.). J Pharmacogn Phytochem 2019, 8(2), 560-4.

The phytochemical constituent of chloroform and methanol extracts of Cuscuta reflexa (whole plant) was identified by phytochemical screening and gas chromatography-mass spectroscopy (GC-MS) techniques. Qualitative analysis of the plant sample revealed the presence of steroids, terpenoids, flavonoids, phenolic compounds and cumarins in both the extracts, but flavonoids, alkaloids, saponines and tannins are present only in methanol extract. The GC-MS analysis of n-hexane soluble part of chloroform extract of C. reflexa revealed eight major peaks with comparatively higher peak area due to Tetrapentacontane (29.98 %), Tris(2,4-di-tert-butylphenyl) phosphite (20.87 %), Tris(2,4-di-tert-butylphenyl) phosphate (13.40 %), 7,9-Di-tert-butyl-1-oxaspiro (4,5)deca-6,9-diene-2,8-dione (2.66 %), 2,4-Di-tert-butylphenol (2.62 %), Dotriacontane (2.31 %), Eicosane (2.28 %) and 4,6-dimethyl-dodecane (2.17 %). Overall, the study summarizes the information regarding the presence of pharmaceutically important bioactive constituents.

1 illus, 3 tables, 29 ref

001402   DEEPA S, PRIYA V (Botany Dep, PSG Coll of Arts & Science, Tamil Nadu - 641 014) : GC-MS analysis on methanolic seed extract of Majidea zanguebarica J. kirk. J Pharmacogn Phytochem 2019, 8(2), 556-9.

The present study was carried out to identify the chemical compounds of Methanolic seed extract of Majidea zanguebarica by GC-MS method. A major phytoconstituents has been studied in the name of classical chemistry, the GC-MS analysis revealed the presence of 20 compound in extract namely 1,4- Anhydro-d-mannitol, Cyclobutane carboxylic acid, cyclobutyl ester, 2,6-Dicyclopentyl-4-methylphenol, Methyl hexadec-9-enoate, l-(+)-Ascorbicacid 2,6-dihexadecanoate, 9-Octadecenal (Z), Butyl dodecanoate, Ethyl 2-methylcyclopropanecarboxylate, Oleic Acid; Methyl 18-methylnona-decanoate, Docosanoic acid, methyl ester, Oleic anhydride and Tetracosanoic acid, methyl ester etc.

1 illus, 1 table, 6 ref

001470   SREEJAI R, RAJU A, BENCHAMIN D, JENSY ROSHAN F, SUJITHA S , KURUP B S (St. Stephen’s Coll, Kerala - 689 695) : Comparative study of anti-microbial and phytochemical analysis of Piper longum and Piper nigrum. J Pharmacogn Phytochem 2019, 8(2), 195-7.

The present research deals with the comparative analysis of Anti-Microbial and Phytochemical properties of Piper longum and Piper nigrum. Six isolates of microorganisms were used to check the antimicrobial properties. Agar well diffusion method and Agar disc diffusion method was employed. The volatile oil content was absent in both plant materials. Water extractive value for P. nigrum was about 7.6 % and P. longum was 12 % alcohol soluble extractive value for P. nigrum was only 2 % and P. longum was found to be 7.6 %. Both plant species are rich in phytochemical constituents such as alkaloids, steroids, flavonoids etc. The present result suggests that alcoholic extract of P. nigrum is a curing agent for diseases caused by E. coli.

1 illus, 4 tables, 12 ref

001388   ALINEZHAD H, AHMADI A, HAJIABBASI P (Organic Chemistry Dep, Mazandaran Univ, Babolsar, Iran, Email: heshmat@umz.ac.ir) : Application of SiO₂ nanoparticles as an efficient catalyst to develop syntheses of perimidines and tetraketones. J Chem Sci 2019, 131(4), 34.

In this paper, we explore the catalytic activity of SiO₂ nanoparticles (NPs) as an eco-friendly, efficient and reusable catalyst in the synthesis of 2,3-dihydro-1H-perimidines as well as tetraketones. For tetraketones syntheses, a simple tandem Knoevenagel condensation following Michael addition procedure is performed by the reaction between benzaldehydes and 5,5-dimethyl-1,3-cyclohexanediones under solvent-free condition using SiO₂ NPs as an efficient solid catalyst. In addition, for 2,3-dihydro-1H-perimidines syntheses, cyclocondensation of various aldehydes with 1,8-diaminonaphthalene is achieved under solvent-free condition using SiO₂ NPs as a catalyst at room temperature. The results showed catalytic enhancement in both synthetic procedures. In this work, 4-(2,3-dihydro-1H-perimidin-2-yl)benzonitrile and 2-(pyridin-4-yl)-2,3-dihydro-1Hperimidine are synthesized as new compounds. Also, reusability study of SiO₂ NPs was done to ensure its applicability as a recycled catalyst in this work.

1 illus, 9 tables, 39 ref

001393   BAHRUJI H, BOWKER M, DAVIES P R (Brunei Darussalam Univ, Gadong BE 1410, Brunei Darussalam, Email: hasliza.bahruji@ubd.edu.bn) : Influence of TiO₂ structural properties on photocatalytic hydrogen gas production. J Chem Sci 2019, 131(4), 33.

A range of commercially produced TiO₂ was deposited with Pd nanoparticles and the activities of the anaerobic, ambient temperature photocatalytic hydrogen production from water-methanol mixture were evaluated. The photocatalytic reactions were carried out in the liquid and gas phase conditions with the rate of hydrogen evolutions were higher was when in the gas phase. The Pd/TiO₂ catalysts were characterised using XRD, N₂ adsorption, infrared and XPS in order to investigate the influence of structural properties of TiO₂ in determining photocatalytic activity. A positive relationship was established in the rate of hydrogen production from the gas and liquid phase conditions with the size of crystallite TiO₂. Analysis of the surface properties of TiO₂ using XPS shows the presence of surface hydroxyl that also influenced the photocatalytic activity of TiO₂.

4 illus, 1 table, 44 ref

001467   SOGUKOMEROGULLARI H G, YALCIN S P, CEYLAN U, AYTAR E, AYGÜN M, RICHESON D S, SÖNMEZ M (Chemistry Dep, Gaziantep Univ, Gaziantep, Turkey, Email: msonmez@gantep.edu.tr) : Synthesis of Fe and Cu metal complexes derived from ‘SNS’ Pincer type ligands and their efficient catalyst precursors for the chemical fixation of CO₂. J Chem Sci 2019, 131(4), 32.

Two novel tridentate SNS pincer type ligands, 2,6-bis[[(2$\text{'}$-methoxyphenyl)thio]methyl]pyridine (L1) and 2,6-bis[[(2$\text{'}$-chlorophenyl)thio]methyl]pyridine (L2), each possessing two sulfur and one nitrogen donor functionalities (SNS), based on 2,6-bis(thioether)pyridine ligands were prepared and metallised with CuCl₂ · 2H₂O and FeCl₂ · 4H₂O metal salts. Two new unanticipated complexes were obtained from the L2 ligand, the dimeric bidentate Cu(I) complex [Cu₂(κ²−L2)₂Cl₂] and tridentate Fe(II) complex [Fe(κ³−L2)Cl₂] while two new tridentate pincer-type complexes M(κ³-L1)Cl₂] (M = Cu, Fe) were formed from the L1 ligand. It was observed that the structure of this Cu(I) complex has a tetrahedral geometry using single crystal Xray diffraction analysis. In addition, catalytic properties of metal complexes towards the formation of cyclic carbonates from CO₂ and epoxides were investigated. The less sterically hindered Fe(II) complex with the L1 ligand [Fe(κ³−L1)Cl₂] (2) showed the best catalytic activity. Several parameters including temperature, time, epoxide identity and CO₂ pressure were investigated to find the optimum catalytic reaction conditions. Moreover, DFT studies of these compounds are presented in the study.

4 illus, 1 table, 72 ref

001451   PANT S, GHORAI P K (Chemical Sciences Dep, Indian Institute of Science Education and Research Kolkata, West Bengal - 741 256, Email: pradip.ghorai@gmail.com) : Impact of length scale of attraction on the dynamical heterogeneity: A molecular dynamics simulation study. J Chem Sci 2019, 131(4), 31.

We investigate the role of the length scale of attraction on the dynamical heterogeneity in threedimensional core-softened (CS) model liquid having interaction potential of two different length scales. Using the simple CS model, we have shown that the presence of heterogeneity is attributed to the existence of attractive interactions in a system. The time scale associated with the peak position of the non-Gaussian parameter is found to be strongly dependent on the temperature for different length scale of attraction. The dynamical heterogeneity dramatically decreases with the increase in temperature. We further characterize dynamical heterogeneity by calculating new non-Gaussian parameter which indicates the existence of much longer relaxation timescale than that suggested by the peak position in the non-Gaussian parameter. Furthermore, we have shown the presence of particles, whose displacement distribution deviates from the Gaussian distribution and contributes towards the origin/presence of heterogeneity.

6 illus, 1 table, 28 ref

001387   AKBAS E, CELIK S, ERGAN E, LEVENT A (Chemistry Dep, Van Yuzuncu Yil Univ, 65080 Van, Turkey, Email: esvakbas@hotmail.com) : Synthesis, characterization, quantum chemical studies and electrochemical performance of new 4,7-dihydrotetrazolo[1,5-a]pyrimidine derivatives. J Chem Sci 2019, 131(4), 30.

In this study, 4,7-dihydrotetrazolo[1, 5-a]pyrimidine derivatives (1–5) were prepared via Multicomponent Cyclocondensation Reactions (MCRs). All structures were determined by using FT-IR, ¹H/¹³C NMR and elemental analyses. The compounds were investigated as corrosion inhibitors using density functional theory (DFT) at the level of B3LYP/6-31G (d, p). According to the calculations, compound 1 appears to be a good inhibitor for corrosion. In addition, the electrochemical properties of the novel systems were investigated by CV.

7 illus, 2 tables, 23 ref

001461   SHAMALA D, SHIVASHANKAR K, CHANDRA, MAHENDRA M (Chemistry Dep, Bangalore Univ, Karnataka - 560 001, Email: shivashankark@gmail.com) : Zinc chloride catalyzed multicomponent synthesis of pyrazolopyridocoumarin scaffolds. J Chem Sci 2019, 131(4), 29.

An efficient synthesis of a series of pyrazolopyridocoumarins is reported by condensation of 4- hydroxycoumarin, benzaldehydes and 1-alkyl-5-amino-pyrazoles in the presence of 10 mol % zinc chloride in ethanol under reflux conditions through one-pot reaction. The significant attraction of this protocol is being a simple procedure, mild reaction condition, and excellent yield. The molecular structure of the compound (4e) is established by single crystal X-ray structure determination.

2 illus, 2 tables, 53 ref

001411   GARCIA-VANEGAS J J, RAMIREZ-VILLALVA A, FUENTES-BENITES A, MARTINEZ-OTERO D, GONZALEZ-RIVAS N, CUEVAS-YANEZ E (Autónoma del Estado de México Univ, Estado de México, Mexico, Email: ecuevasy@uaemex.mx) : Synthesis and in-vitro biological evaluation of 1,1-diaryl-2-(1,2,3)triazol-1-yl-ethanol derivatives as antifungal compounds flutriafol analogues. J Chem Sci 2019, 131(4), 27.

A small library of diverse 1,1-diaryl-2-(1,2,3)triazol-1-yl-ethanol derivatives was designed and prepared from CuAAC reaction as the key step. The molecular structure of some representative compounds was unambiguously determined from X-ray diffraction studies. In addition, synthesized 1,2,3-triazoles were evaluated for activity against filamentous fungi (Mucor hiemalis, Aspergillus fumigatus, Trichosporon cutaneum, and Rhizopus oryzae) and yeasts that belong to the genus Candida. Two compounds showed high activity against C. utilis (MIC 0.5 μg/mL) and A. fumigatus (MIC 4 μg/mL) which is close to itraconazole used as reference compound.

3 illus, 4 tables, 21 ref

001433   LI Z, LU H, LIU Z, MA X (Northwest Normal Univ, Lanzhou- 730 070, People’s Republic of China, Email: lizheng@nwnu.edu.cn) : Sequential Michael addition/retro-Claisen condensation of 1,3-diarylpropan-1,3-diones with nitrostyrenes: One-step synthesis of 4-nitro-1,3-diarylbutan-1-ones. J Chem Sci 2019, 131(4), 26.

The sequential Michael addition/retro-Claisen condensation of 1,3-diarylpropan-1,3-diones with nitrostyrenes is described. 4-Nitro-1,3-diarylbutan-1-ones were efficiently synthesized in good to high yield under mild, transition-metal-free condition. This one-step method involving sequential carbon-carbon bond formation and cleavage provides a good alternative to the synthesis of various γ -nitro ketones.

2 tables, 29 ref

001489   YAMINI V, REDDY K M, KRISHNA A S, LAKSHMI J K, GHOSH S (Organic Synthesis and Process Chemistry Div, CSIR-Indian Institute of Chemical Technology, Telangana - 500 007, Email: subhash@iict.res.in) : Formal total synthesis of mandelalide A. J Chem Sci 2019, 131(3), 25.

In this article the formal total synthesis of mandelalide A has been described in details. The highly convergent and flexible strategy developed for mandelalide A involved the construction of key building blocks ent-9 and 7, and their assembly to the target compound. For the synthesis and coupling of these building blocks, the Brown’s crotylation, Sharpless asymmetric dihydroxylation followed by in situ Williamson type etherification, modified Prins cyclization, Masamune-Roush olefination and Heck cyclization were employed, the latter being crucial for the highly stereoselective formation of the macrocycle of mandelalide A. Initially, Julia Kocienski olefination, ring-closing metathesis reaction were investigated for the synthesis of the aglycone of the proposed structure of the mandelalide A, and found to be unsuccessful.

1 illus, 2 tables, 25 ref

001407   DINDA S, PATRA S C, GANGULY S (Chemistry Dep, St. Xavier’s Coll, West Bengal - 700 016, Email: icsgxav@gmail.com) : Rhodium(III) complex with pyrene-pyridyl-hydrazone: Synthesis, structure, ligand redox, spectral characterization and DFT calculation. J Chem Sci 2019, 131(3), 24.

The pyridylhydrazone ligand incorporating a pendant pyrene moiety HL has been synthesized starting from 2-hydrazinopyridine and its coordinating behaviour towards rhodium(III) have been scrutinized. The complex of type [RhL(PPh₃)₂Cl₂], incorporating five-membered chelate ring has been isolated and the structure has been authenticated by single-crystal X-ray diffraction study. The ligand exhibits an oxidative response at ∼1.2 V upon coordination with rhodium(III) and the optoelectronic properties as well as theoretical exploration have been performed by the density functional theory (DFT) as well as time-dependent density functional theory (TD-DFT) analyses.

6 illus, 3 tables, 50 ref

001442   MOHAJERI S, DOLATI A, REZAIE S S (Materials Science and Engineering Dep, Sharif Univ of Technology, Tehran, Iran, Email: smohajeri@alum.sharif.edu) : Electrochemical sensors based on functionalized carbon nanotubes modified with platinum nanoparticles for the detection of sulfide ions in aqueous media. J Chem Sci 2019, 131(3), 21.

Vertically aligned carbon nanotube (CNT) arrays were synthesized by thermal chemical vapor deposition (CVD) on stainless steel substrates coated by cobalt nanoparticles as catalyst. Morphological and elemental analyses conducted by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that bamboo-like CNTs were blocked by Co nanoparticles at the tips. The fabricated nanotubes underwent functionalization by electrochemical oxidation in sulfuric acid, and the subsequent structural studies, as well as Fourier transform infrared (FTIR) spectroscopy confirmed that the tips of functionalized CNTs were opened while oxygenated functional groups were generated at the sidewalls and tube endings. In order to enhance the catalytic performance of the functionalized CNT-based electrodes, platinum nanoparticles were deposited on nanotubes by the potentiostatic and pulse potential electrodeposition processes, and the optimum operating parameters in both techniques were determined. The catalytic activities of these two electrodes towards methanol oxidation were determined by cyclic voltammetry (CV) testing, and a superior electrocatalytic activity and poisoning tolerance were detected for the electrode prepared by pulse deposition. The sensing performance of the pulse plated Pt/CNT electrode for the electrochemical detection and oxidation of dissolved sulfide ions was investigated. A sensitivity of 0.632 μA μM⁻¹cm⁻² and a detection limit of 0.26 μM were obtained, indicating the enhanced capabilities of the developed sensor as a promising candidate for various industrial and environmental applications.

15 illus, 2 tables, 44 ref

001395   BHAT S K, PRASAD J D, HEGDE M S (Chemistry Dep, Mangalore Univ, Mangalore - 574 199, Email: jprasad2003@gmail.com) : Recyclable Pd ionic catalyst coated on cordierite monolith for high TOF Heck coupling reaction. J Chem Sci 2019, 131(3), 20.

Pd²⁺ ionic catalyst, Ti_0.97Pd_0.03O_1.97 was coated over cordierite monolith by solution combustion method. The catalyst coated on the cordierite is nano-crystalline as seen from XRD studies. Coated catalyst was used for Heck coupling reactions with different substrates of aryl halides and olefins. Thus handling nanocrystalline catalyst powder is avoided by fixing it on a solid catalyst cartridge. Heck coupled products were characterized using ¹H NMR, ¹³C NMR, Mass and FTIR spectroscopy. This catalyst showed high selectivity towards Heck coupling reaction. Turnover frequencies (TOF) for each of the reactions were found to be very high. The catalyst was recycled up to 7 times with total TOF 3017 h⁻¹, which is found to be a new green technique in the Heck coupling reaction.

7 illus, 2 tables, 32 ref

001465   SINHA B, BHATTACHARYA M, SAHA S (Chemistry Dep, North Bengal Univ, West Bengal - 734 013, Email: sanjoychem83@yahoo.com) : Transition metal complexes obtained from an ionic liquid-supported Schiff base: Synthesis, physicochemical characterization and exploration of antimicrobial activities. J Chem Sci 2019, 131(3), 19.

An ionic liquid-supported Schiff base 1-{2-(2-hydroxy-5-chlorobenzylamine) ethyl}-3-methy limidazolium tetrafluoroborate and its Co(II), Ni(II), Cu(II), Mn(III), Fe(III) and Cr(III) complexes were synthesized and characterized by various analytical (elemental analysis, molar conductance and magnetic susceptibility measurements) and spectroscopic (PXRD, SEM, ESI-MS, UV-Visible, FT-IR, ¹H NMR and ¹³C-NMR) methods. Based on these spectral data and spectra, tetra coordinated and hexacoordinated geometries were assigned for the synthesized metal complexes. Molar conductance of the complexes showed their (1:2) electrolytic nature. The Schiff base ligand and its complexes were screened for in vitro antimicrobial activities against some naturally available gram positive and gram negative bacteria to assess their inhibition potentials. Maximum inhibition zone was produced by the Cu(II) complex (5a) in plates of Klebsiella pneumoniae while the minimum inhibition zone was produced by in plates of Bacillus cereus.

9 illus, 56 ref

001422   JAHED F S, GALEHASSADI M, DAVARAN S (Chemistry Dep, Azarbaijan Shahid Madani Univ, Tabriz, Iran, Email: mg-assadi@azaruniv.ac.ir) : A novel 1,2,3-benzotriazolium based ionic liquid monomer for preparation of MMT/poly ionic liquid (PIL) pH-sensitive positive charge nanocomposites. J Chem Sci 2019, 131(3), 18.

In this work, a new ionic liquid (IL) with two acidic and vinylic functional groups based on 1,2,3- benzotriazolium cation was synthesized. This IL monomer was intercalated into the montmorillonite (MMT) layers by the ion exchange reaction and subsequently copolymerized with the IL monomer and methacrylic acid in order to obtain positive charge pH-sensitive nanocomposites. The structure of the IL monomer was characterized by FT-IR and ¹H-NMR spectroscopy, and the structure of the nanocomposites was studied and confirmed by the FT-IR, XRD, TGA, SEM, and EDX data. These pH-sensitive nanocarriers were used to load and in vitro release of the anticancer drug, methotrexate (MTX) in pH=4 and pH=7.4. The results showed that the release is pH dependent and more effective in acidic pH; therefore, these nanocarriers have potential to be used for cancer therapy.

9 illus, 24 ref

001409   DUBEY H K, VERMA C, RAI U S, KUMAR A, LAHIRI P (Chemistry Dep, Banaras Hindu Univ, Varanasi - 221 005, Email: plahiri16@yahoo.com) : Synthesis, characterization and properties of nickel based zinc ferrite nanoparticles. Indian J Chem Sec A 2019, 58A(04), 454-8.

A cost effective and environmental friendly sol-gel auto-combustion technique has been used to synthesize spinel ferrite nanoparticles of Ni_xZn_1-xFe₂O₄ (x = 0.0, 0.5 and 1.0). They were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDX). While their magnetic properties have been measured at room temperature using a Magnetic Properties Measurement System (MPMS) quantum design magnetometer, the LCR meter (PSM 1735, NumetriQ 4^th Ltd U.K.) has been used to study their dielectric properties with variable frequency in the range, 1 Hz–5 MHz. The XRD analysis suggests the presence of cubic spinel structure of ferrites with an average crystallite size of 45–79 nm. The dielectric constant and loss tangent of the samples show a normal dielectric behavior. The variation of dielectric behavior with the frequency is due to the Maxwell-Wagner type interfacial polarization and hopping of electrons between the Fe²⁺ and Fe³⁺ ions. The magnetic studies reveal that addition of Zn²⁺ drastically affects the magnetic properties.

4 illus, 1 table, 22 ref

001453   PASWAN S, ANJUM A, SINGH A P, DUBEY R K (Chemistry Dep, Allahabad Univ, Allahabad - 211 002, Email: sikandar0551@gmail.com) : Synthesis and spectroscopic characterization of lanthanide complexes derived from 9,10-phenanthrenequinone and Schiff base ligands containing N, O donor atoms. Indian J Chem Sec A 2019, 58A(04), 446-53.

A series of mixed ligand lanthanide complexes of general formula [Ln(PhenQ)(L_1-3) (NO₃)₂(H₂O)_n] [where n = 0, Ln = Yb(III); n = 1, Ln = Dy(III); and n = 2, Ln = Nd(III)] have been derived from 9,10-phenanthrenequinone (PhenQ) and Schiff bases (L_1-3H) [where, L₁H = (E)-2-methoxy-6-((thiazol-2-ylimino) methyl) phenol, L₂H = (E)-4-(2-hydroxy-3-ethoxybenzylidineamino) benzoic acid and L₃H = 2-((p-tolylimino) methyl) phenol] containing N, O donor atoms. These metal complexes have been characterized by elemental analysis, infrared, UV-Vis, Thermogravimetric analysis, Powder X-ray diffraction and ESI-Mass spectrometry. Surface morphology of the synthesized complexes has been analysed by SEM-EDX and they appear to have stone-like surface morphology (rough, with indefinite shape). The metal complexes of Nd and Dy have been found to be ten coordinated, whereas metal complex of Yb is found to be eight coordinated which has tentatively been proposed by spectroscopic techniques.

3 illus, 3 tables, 35 ref

001446   NARSIMHA N, JAHEER M, REDDY P R, SUDEEPA K, DEVI C S (Chemistry Dep, Osmania Univ, Hyderabad, Telangana, Email: dr_saraladevich@yahoo.com) : Spectro-analytical and in vitro biological studies of novel nalidixic acid hydrazone and its transition metal complexes. Indian J Chem Sec A 2019, 58A(04), 436-45.

The novel and potential chelating agent derived from Nalidixic acid and its binary Cu(II), Ni(II) and Co(II) metal complexes have been synthesized and characterized by elemental analyses, ¹H-NMR, Mass, UV-vis, FT-IR, TGA, SEM-EDX, ESR and magnetic susceptibility measurements. All the systems of the present study have been screened for antimicrobial activity against bacterial species Bacillus (Gram +) and Escherichia coli (Gram -) and fungal species Sclerotium rolfsii and Macrophomina phaseolina exhibited an enhanced activity of metal complexes over unbound free chelating agent. The interaction studies of metal complexes with Calf-thymus DNA (CT-DNA) investigated by UV-visible and fluorescence titrations revealed the intercalation mode of binding. Further MTT assay performed on HeLa (human cervical cancer) and A549 (human lung tumor) cell lines revealed the IC₅₀ values for the studied title compounds. In addition computer-aided molecular docking technique carried out with all title compounds employing molecular target DNA (PDB ID: 1N37), furnished docking scores and mode of binding for geometry optimized molecular structures of title compounds.

6 illus, 3 tables, 57 ref

001463   SINGH V K, GUPTA S, GUPTA A (Chemistry Dep, Udai Pratap Autonomous Coll, Varanasi - 221 002, Email: ashu1809@gmail.com) : Exploring the mechanism of conversion of monosulfiram into disulfiram. Indian J Chem Sec A 2019, 58A(04), 429-435.

Monosulfiram is a drug used topically in the treatment of scabies. Upon its application it shows similar effects as seen in case of disulfiram, a drug used in alcohol aversion therapy. Previous reports have concluded a light induced conversion of monosulfiram (MS) into disulfiram (DS). In the present study a computational approach has been involved to investigate the mechanism of this conversion. Structures have been optimized using MP2 and DFT approach. Insights on their reactivities have been assessed through conceptual DFT. Time-dependent DFT investigation has been undertaken to obtain excitation energies for singlet and triplet states. Bond dissociation energies of both molecules have also been obtained and analyzed. It has been found that conversion of MS into DS occurs in both thermal and photochemical situations.

2 illus, 4 tables, 37 ref

001408   DU H, SUN X, ZHAO S (Xinjiang Normal Univ, Urumqi 830054, China, Email: 175790509@qq.com) : Sonochemical synthesis of palladium nanoparticles and its electrocatalytic activity for oxidation of formic acid. Indian J Chem Sec A 2019, 58A(03), 330-4.

Monodispersed palladium nanoparticles have been synthesized from palladium(II) chloride aqueous solution by ultrasonication without gas protection and in the absence of an external reducing agent, by the addition of a small quantity of polyvinylpyrrolidone (PVP). The monodispersity and columnar crystallinity of palladium nanoparticles have been observed using TEM and HRTEM respectively. The five X-ray diffraction peaks of the metallic Pd indicated that Pd(II) ions have been reduced to palladium atoms Pd(0). The formation of nanoparticles has been investigated using FT-IR spectroscopy. Results show that the PVP can protect metal nanoparticles via the coordination of the PVP carbonyl group to the palladium atoms and the steric effect of the PVP polymer long chain. The activity towards formic acid oxidation reaction (FAOR) has also been measured.

4 illus, 26 ref

001410   FAN W T, ZHU H, XU Q Q, KOU J F, LIU F Y (Yunnan Normal Univ, Yunnan, 650 500, PR China, Email: kjf416@163.com) : Synthesis, crystal structure and properties of a 1D cadmium(II) coordination polymer with 2,6-dimethyl-3,5-bis(pyrazo-3-yl)pyridine. Indian J Chem Sec A 2019, 58A(03), 326-9.

A new coordination polymer {[Cd(H₂dmbpzp)I₂]⋅CH₃CH₂OH}_n (H₂dmbpzp = 2,6-dimethyl-3,5-bis(pyrazo-3-yl)pyridine) has been prepared by the reaction of H₂dmbpzp in aqueous ethanolic solution at room temperature with CdI₂. The compound has been characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA) and single crystal X-ray diffraction. Photoluminescence properties have also been examined. The complex exhibits a 1D chain structure.

4 illus, 2 tables, 33 ref

001491   ZHAO Y, HAN Y, SHI L, YANG L, ZHANG Z, JIAO J, LIU F (Hebei Normal Univ of Science & Technology, Qinhuangdao 066004, Hebei Province, PR China, Email: zhaoyingsjz@163.com) : Synthesis and luminescent properties of red-emitting Ba₃Al₂O₆:Eu³⁺ phosphor. Indian J Chem Sec A 2019, 58A(03), 321-5.

Ba₃Al₂O₆:Eu³⁺ phosphors have been prepared by solid state reaction method. X-Ray powder diffraction (XRD) analyzed and confirmed the phase formation of BaAl₂O₆:Eu³⁺ and the doping of Eu³⁺ did not change the crystal structure. The scanning electron microscope (SEM) image exhibited the irregular morphology of Ba₃Al₂O₆:Eu³⁺ particles, the particle diameter of the sample has not been found to be very uniform. The photoluminescence excitation (PLE) and emission (PL) spectra have been investigated. The PLE spectra indicated the phosphor to be suitable for being excited by near UV and blue light. From the PL spectra, the optimum doping concentration of Eu³⁺ has been found to be 9 %. Meanwhile, it is concluded that the addition of co-solvent can reduce the synthesis temperature. The color coordinates of all the samples have been recorded in the red area. All the results indicated that BaAl₂O₆:Eu³⁺ has been found to be a potential red phosphor candidate for high efficiency fluorescence lamps and for other related applications.

8 illus, 18 ref

001452   PASHA N, KUMARI P K, VAMSIKRISHNA N, LINGAIAH N, SUBHASHINI N J P, SHIVARAJ (Chemistry Dep, Osmania Univ, Hyderabad - 500 007, Email: nayeem77sk@gmail.com) : Conversion of fructose into 5-hydroxymethylfurfural over mesoporous-ZrO₂-phosphomolybdic acid nanocomposite catalysts. Indian J Chem Sec A 2019, 58A(03), 313-20.

A series of phosphomolybdic acid (MPA) with varying content, incorporated into the mesoporous zirconia (ZMPA) catalysts have been prepared by surfactant-assisted sol-gel copolymerization technique. These catalysts have been evaluated for selective dehydration of fructose to 5-hydroxymethyl furfural (HMF). The catalysts have been characterized by X-ray diffraction, nitrogen physisorption, Fourer-transform infrared spectroscopy, temperature programmed disorption, pyridine adsorbed FT-infrared spectroscopy and transmssion electron microscopy. The characterization results suggest that these catalysts possess ordered mesoporous structure with Keggin heteropoly molybdate. Moreover the incorporation of phosphomolybdic acid into mesoporous zirconia resulted in the generaton of more number of strong acidic sites. These catalysts exhibited about 80 % HMF yield within 30 min of reaction time. The existence of relatively strong interactions between the MPA Keggin units with ZrO₂ mesoporous structure played a crucial role in fabricating the stable heterogeneous catalyst. This catalyst has been found to be reusable with constant activity.

4 illus, 3 tables, 47 ref

001421   IGLESIAS A L, MIRANDA-SOTO V, POMPA-MONROY D A, MARTINEZ-ORTIZ J G, DIAZ-TRUJILLO G C, VILLARREAL-GOMEZ L J (Autónoma de Baja California Univ, Baja California, México, Email: aiglesias@uabc.edu.mx) : Biological activity of new Schiff base compounds derived from substituted 3-Aminopyrazoles, the role of Pyrazole on bioactivity. Indian J Pharm Sci 2019, 81(2), 333-43.

A series of new Schiff base compounds derived from substituted 3-aminopyrazoles and dialdehydes were synthesized and characterized by ¹H, ¹³C nuclear magnetic resonance, Fourier-transform infrared, ultraviolet-visible, gas chromatography-mass spectrometry and high resolution mass spectrometry. The antimicrobial activity of the ligands was screened against the bacterial Gram-negative species Escherichia coli, Pseudomonas aeruginosa and the Gram-positive species Staphylococcus aureus, using gentamycin as a control. Minimal inhibitory concentration was determined by the microdilution method. The anticancer activity was evaluated against HCT116 colorectal cancer cells, with etoposide as a control, using MTSPMS assay and expressed as IC₅₀ values. The pharmacological studies showed that in general ligands exhibited broad-spectrum antibacterial activity, which decreased in the following order Escherichia coli>Staphylococcus aureus>Pseudomonas aeruginosa. Bis(imino)pyridine Schiff bases (2a-e) have excellent activity towards Staphylococcus aureus; compounds 2a and 2d (3.125 µg/ml) are several times more potent than the control drug, whilst bis(imino)benzene compounds (3a-e) showed significant pathogenic activity toward Pseudomonas aeruginosa with MIC values of 6.25 µg/ml for 3c and 3e. Compound 2c showed higher cytotoxicity (0.40 µM) than etoposide. The results suggest that pyrazole ring as well as the substitution pattern on the heterocyclic moiety have effect on bioactivity.

3 illus, 5 tables, 51 ref

001479   SWAIN R P, SUBUDHI B B, RAMESH P (Siksha O Anusandhan Univ, Bhubaneswar - 751 003, Email: ranjit.prasad797@gmail.com) : Effect of solutol HS 15 in solid dispersions of pioglitazone hydrochloride: In vitro and in vivo evaluation. Indian J Pharm Sci 2019, 81(2), 317-25.

Poor aqueous solubility and slow dissolution rate adversely affects bioavailability of pioglitazone hydrochloride. This study was undertaken to improve dissolution and bioavailability of pioglitazone hydrochloride through preparation of stable solid dispersions by melting and solvent evaporation method using Solutol HS 15. Solubility of pioglitazone hydrochloride was enhanced by 9 to 49 fold as the drugcarrier ratio was increased in solid dispersions as compared to pure drug. Furthermore, compared to pure drug or physical mixture, solid dispersions significantly improved the dissolution rate and the extent of drug release. Solid dispersions at 1:7 drug:Solutol HS 15 weight ratio showed complete and rapid drug release within 15 min at pH 1.2. The Fourier-transform infrared spectrum revealed the chemical compatibility with Solutol HS 15. Differential scanning calorimetry and X-ray powder diffraction pattern revealed a change in crystallinity to amorphous state that supported the enhancement of solubility of pioglitazone hydrochloride with Solutol HS 15. In vivo test showed that Solutol HS 15-based solid dispersions showed higher AUC_0-t and C_max, which was ~4 times higher than that of pure pioglitazone (p<0.05) implying solid dispersions could be effective in increasing the bioavailability. In conclusion, solid dispersions with Solutol HS 15 prepared using solvent evaporation method appeared to be a promising technique to improve the dissolution, bioavailability and stability of pioglitazone hydrochloride.

8 illus, 2 tables, 37 ref

001450   PANDYA K D, SHAH N V, GOHIL D Y, SETH A K, AUNDHIA C J, PATEL S S (Pharmacy Dep, Sumandeep Vidyapeeth, Vadodara - 391 760, Email: nimspharma@gmail.com) : Development of risedronate sodium-loaded nanosponges by experimental design: Optimization and in vitro characterization. Indian J Pharm Sci 2019, 81(2), 309-16.

The present investigation focussed on the development of a novel strategy to enhance the bioavailability of risedronate sodium, which has poor and erratic absorption. Nanosponges were statistically developed by full 3² factorial design using Design of Experiment software considering concentration of polymer and stabilizer as independent variables and particle size and entrapment efficiency as experimental responses by utilizing the modified quasi-emulsion solvent diffusion technique. Optimized formulation showed 67.27± 1.05 % entrapment efficiency, 155.8±2.17 nm particle size and –35.4 mV of zeta potential. The data from in vitro release study showed burst release for initial 2 h followed by slow and sustained release up to 24 h, which followed a diffusion-controlled release mechanism by the Higuchi model. Scanning electron microscopy study showed uniformly discrete spherical particles with porous surface without any agglomeration. Stability study demonstrated no significant changes in particle size, entrapment efficiency and in vitro release, which indicated that the nanosponge formulation was stable. In conclusion, it appeared that the nanosponges were a suitable nanocarrier system that could play a significant role in improving osteoporotic condition.

6 illus, 4 tables, 24 ref

001460   SHAH U, SHAH K, PATEL R (Charotar Univ of Science and Technology, Anand - 388 421, Email: umangshah.ph@gmail.com) : Stability-indicating analytical method development using quality by design approach for simultaneous estimation of ezetimibe and glimepiride. Indian J Pharm Sci 2019, 81(2), 273-81.

Stability-indicating reversed-phase high-performance liquid chromatography method was developed and validated for the simultaneous estimation of ezetimibe and glimepiride. Chromatographic separation was achieved with a Shimadzu’s high performance liquid chromatograph and PhenomenexL1 analytical C18 column with a mobile phase of acetonitrile:ammonium acetate buffer (30 mM):methanol (50:45:5 %, v/v/v). The flow rate was set at 1.5 ml/min and the detection wavelength was 232 nm. Quality by design approach was employed for optimization of method parameters like proportion of mobile phase, concentration of buffer and a model highlighting the design space was generated. This developed chromatographic method gave well resolved symmetric peaks. Ezetimibe and glimepiride were eluted at 6.7 and 4.4 min, respectively. This method was validated according to International Conference on Harmonisation Q2(R1) guideline. The method was linear in range of 50-400 µg/ml for ezetimibe and 5-40 µg/ml for glimepiride with r² =0.9999 and 0.9996, respectively. The sample recoveries were in good agreement with the respective label claim, which suggested non-interference from formulation additives in the estimation. Forced degradation studies were carried out and the stressed samples were analysed using the developed methods.

5 illus, 10 tables, 23 ref

001490   ZHANG H Y (Biochemistry Dep, Weihai Vocational Coll, Shandong, China, Email: haiyi_zhang@163.com) : Preparation and evaluation of activity of highly-soluble anticancer protein drug TAT_m-survivin (T34A). Indian J Pharm Sci 2019, 81(2), 266-72.

TAT_m-survivin (T34A), an anticancer protein drug, displayed pro-apoptotic bioactivity against various cancer cells. It was expressed in Escherichia coli as inclusion bodies. To test the bioactivity of soluble TAT_msurvivin (T34A), a feasible strategy was first developed for the soluble expression and purification. Effect of zinc ion and induction temperature was investigated to improve the solubility and overall production level of TAT_m-survivin (T34A). High solubility (92 %) was achieved by addition of zinc ion and temperature downshift after induction. An efficient protocol of purification was established by heat release, ammonium sulphate precipitation, anion exchange and heparin affinity chromatography. Purified TAT_m-survivin (T34A) was obtained with a purity of 96 %, which inhibited the proliferation of human pancreas carcinoma cell lines SW1990. In comparison to denatured TAT_m-survivin (T34A), soluble TAT_m-survivin (T34A) did not exhibit higher bioactivity as expected. This study represented a novel strategy to obtain highly soluble form of TAT_m-survivin (T34A) and would provide useful information for production of other soluble tat-mediated fusion proteins.

3 illus, 3 tables, 40 ref

001398   BUKHARI S A, QASIM M, MASOUD M S, MAHMOOD-UR-RAHMAN, ANWAR H, WAQAS A, MUSTAFA G (Biochemistry Dep, Government Coll Univ, Faisalabad - 38060, Email: gmustafa_uaf@yahoo.com) : Evaluation of medicinally important constituents of Cotoneaster afghanicus G.Klotz collected from Baluchistan region of Pakistan. Indian J Pharm Sci 2019, 81(2), 259-65.

Cotoneaster afghanicus G.Klotz, indigenous to mountainous parts of China, Afghanistan and Pakistan is also present in Baluchistan region of Pakistan and has medicinally important fixed oils and essential oils. The oils and chemical compounds extracted from Cotoneaster afghanicus were subjected to chemical analyses and evaluation of antioxidant, antibacterial, biofilm inhibiting, thrombolytic and cytotoxic effects. Fixed and essential oils were characterized by gas chromatography-mass spectrometry, which enabled identification of 4 and 14 compounds. Fixed oil showed significant antioxidant (64.67 % scavenging of 2,2-diphenyl-1- picrylhydrazyl radical) and antibacterial (7 mm zone of inhibition for Gram-positive bacteria) activities. Ethanol extract (355 mg/100 g of sample) showed highest biofilm inhibitory activity (54.63 %) among the extracted compounds. Essential oil and ethanol extract also showed notable antioxidant effect with less cytotoxic effect indicating that these are good biologically active agents. The results of this study suggest to further investigate the use of extracted oils and chemical compounds as treatments for local ailments.

5 illus, 3 tables, 32 ref