scholarly journals Synthesis, Characterization and Antibacterial Properties of Nickel(II) Complex with 4-Aminoantipyrine Ligand

2021 ◽  
Vol 21 (2) ◽  
pp. 391
Author(s):  
Yusica Amalia Rasyda ◽  
Mudhita Kusuma Widowati ◽  
Soerya Dewi Marliyana ◽  
Sentot Budi Rahardjo
Keyword(s):  
Free Ligand ◽  
Antibacterial Properties ◽  
Carbonyl Oxygen ◽  
Bidentate Ligand ◽  
The Novel ◽  
Scanning Calorimetry ◽  
Paramagnetic Property ◽  
Nickel Ion ◽  
Amine Nitrogen ◽  
Two Peaks

The novel nickel(II) complex has been successfully synthesized through the reaction of Ni(NO3)2·6H2O with 4-aminoantipyrine (AAP) ligand in a 1:3 mole ratio of Ni(II) to AAP. The complex was characterized using UV-Vis, Atomic Absorption Spectroscopy (AAS), Infrared spectrophotometry (IR), Thermogravimetry/Differential Scanning Calorimetry (TG/DSC), conductivity, and magnetic susceptibility. The complex formula was [Ni(AAP)3](NO3)2·5H2O. AAP was a bidentate ligand that coordinated through the primary amine nitrogen and the carbonyl oxygen to the nickel ion. The electronic spectra of the complex displayed two peaks at 646 nm and 385 nm in accordance with the 3A2g(F) → 3T1g(F) and 3A2g(F) → 3T1g(P) transitions, respectively. This complex gave a paramagnetic property with the effective magnetic moment (µeff) of 2.96 BM and the shape of an octahedron. The antibacterial test of this complex showed higher activity than the metal and its free ligand.

Synthesis, characterization, and structures of zircona- and boracyclosiloxanes with ferrocenyl substituents

2002 ◽  
Vol 80 (11) ◽  
pp. 1469-1480 ◽  
Author(s):  
Karena Thieme ◽  
Sara C Bourke ◽  
Juan Zheng ◽  
Mark J MacLachlan ◽  
Fojan Zamanian ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Differential Scanning Calorimetry ◽  
Thermogravimetric Analysis ◽  
Ring Opening ◽  
Ring Opening Polymerization ◽  
The Novel ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Multinuclear Nmr Spectroscopy

The novel zirconatetraferrocenylcyclotrisiloxane Cp2Zr(OSiFc2)2O (6), dizirconatetraferrocenylcyclotetrasiloxane [Cp2Zr(OSiFc2)O]2 (7), boratetraferrocenylcyclotrisiloxane (C6H5)B(OSiFc2)2O (8), and diboratetraferrocenylcyclotetrasiloxane [(C6H5)B(OSiFc2)O]2 (9) with ferrocenyl (Fc = Fe(η-C5H4)(η-C5H5)) substituents at silicon have been prepared from the reactions of Cp2Zr(NMe2)2 and PhBCl2 with diferrocenylsilanediol Fc2Si(OH)2 (3) and tetraferrocenyldisiloxanediol [Fc2SiOH]2O (5). The compounds were characterized by mass spectrometry, elemental analysis, UV–vis, IR, Raman, and multinuclear NMR spectroscopy, as well as single crystal X-ray diffraction. Thermogravimetric analysis and differential scanning calorimetry investigation of 6–9 showed that the cycles decompose before they can undergo any thermal ring-opening polymerization. In addition, no polymerization was detected in the presence of either KOSiMe3 or HOTf. The bulky ferrocenyl substituents on the Si atoms are likely to be at least partially responsible for the inability of these heterocycles to undergo ring-opening polymerization. Key words: heterocyclosiloxanes, ferrocenyl.

scholarly journals Bioinorganic Relevance of Some Cobalt(II) Complexes with Thiophene-2-glyoxal Derived Schiff Bases

2009 ◽  
Vol 6 (1) ◽  
pp. 99-105 ◽  
Author(s):  
Prashant Singh ◽  
Shanu Das ◽  
Rajesh Dhakarey
Keyword(s):  
Spectral Data ◽  
Schiff Bases ◽  
Metal Ion ◽  
Free Ligand ◽  
Antimicrobial Activities ◽  
Carbonyl Oxygen ◽  
Azomethine Nitrogen ◽  
Ligand Field ◽  
Filter Paper Disc ◽  
Electronic Spectral Data

Complexes of Co(II) with two new Schiff bases TEAB [2-hydroxy-4-{[2-oxo-2-(thiophen-2-yl)ethylidene]amino}benzoic acid] and TEPC [N-[2-oxo-2-(thiophen-2-yl)ethylidene]pyridine-3-carboxamide] have been synthesized and characterized with the help of elemental analysis, magnetic, mass,1H-NMR,13C-NMR, IR and electronic spectral data. IR spectra manifest the coordination of the ligand to the metal ion through the carbonyl oxygen, azomethine nitrogen and thienyl sulphur atoms. With the help of electronic spectral data various ligand field parameters were also calculated. All these studies reveal the distorted octahedral Co(II) complexes. Synthesized compounds have also been screened against some micro organismsviz, Escherichia coli, Proteus vulgaris, Aspergillus nigerandAspergillus flavuswith the help of ‘filter paper disc’ technique. It has been observed that the antimicrobial activities of metal complexes are higher than that of the free ligand.

Polymeric nanoparticles-based multi-functional coatings on NiTi alloy with nickel ion release control, cytocompatibility, and antibacterial performance

2019 ◽  
Vol 43 (3) ◽  
pp. 1551-1561 ◽  
Author(s):  
Long Meng ◽  
Yunan Wu ◽  
Kai Pan ◽  
Ye Zhu ◽  
Xiaojie Li ◽  
...  
Keyword(s):  
Polymeric Nanoparticles ◽  
Niti Alloy ◽  
Antibacterial Properties ◽  
Functional Coatings ◽  
Ion Release ◽  
Nickel Ion ◽  
Antibacterial Performance ◽  
Release Control

Photo-cross-linked quaternized copolymer coatings on NiTi alloy show prominent inhibition of nickel ion release and antibacterial properties.

scholarly journals Synthesis, Structure, and Biological Assays of Novel Trifluoromethyldiazepine–Metal Complexes

2020 ◽  
Vol 73 (1) ◽  
pp. 49
Author(s):  
Mariana Rocha ◽  
Gustavo A. Echeverría ◽  
Oscar E. Piro ◽  
Jorge J. Jios ◽  
Rocío D. I. Molina ◽  
...  
Keyword(s):  
Metal Complexes ◽  
Biofilm Formation ◽  
Crystal Packing ◽  
Free Ligand ◽  
Antibacterial Properties ◽  
Bactericidal Effect ◽  
Biological Assays ◽  
Additional Information ◽  
Gram Positive Bacteria ◽  
Mechanism Of Inhibition

A new series of CuII, NiII, CoII, and MnIII complexes have been synthesised from the (6Z)-6-(7-trifluoromethyl-1,2,3,4-tetrahydro-5H-1,4-diazepin-5-ylidene)cyclohexa-2,4-dien-1-one (HDZP) ligand. These complexes were characterised by elemental, spectroscopic (IR and UV-vis), and thermal analysis. The crystal structure of Cu-DZP was solved by X-ray diffraction methods. The complex crystallises in the monoclinic P21/c space group, with two molecules per unit cell. The crystal lattice is stabilised by different intra and intermolecular interactions. Hirshfeld surface analysis was employed to obtain additional information about interactions that are responsible for the crystal packing. Quantitative examination of the fingerprint plots indicated the dominant contribution of H⋯H and H⋯X (X=O, F) interactions in the crystal packing. In addition, C–H⋯chelate ring (CR) and C–H⋯π interactions are described in detail and evaluated using DFT calculations. The antibacterial properties and the mechanism of inhibition of the main bacterial resistant mechanism, the biofilm, of the metal complexes and free ligand were investigated. [Mn(DZP)3]·2H2O was the most active complex against the Pseudomonas aeruginosa biofilm formation with an inhibition of 40%. However, none of the complexes inhibit more than 25% of the Gram negative bacteria microbial development. The most meaningful result was the bactericidal effect of [Co(DZP)2(H2O)2]·2H2O against the Gram positive bacteria, Staphylococcus aureus, which inhibits the bacterial development and significantly reduces the biofilm formation at low concentration.

scholarly journals The novel modeling approach for the study of thermal degradation of PMMA/nanooxide systems

2019 ◽  
Vol 38 (1) ◽  
pp. 95
Author(s):  
Mirjana Jovicic ◽  
Oskar Bera ◽  
Katalin Meszaros Szecsenyi ◽  
Predrag Kojic ◽  
Jaroslava Budinski-Simendic ◽  
...  
Keyword(s):  
Thermal Degradation ◽  
Degradation Kinetics ◽  
The Novel ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
Total Mass Loss ◽  
Thermal Changes ◽  
Silica Alumina ◽  
Individual Contributions ◽  
Kinetics Of

PMMA (poly(methyl methacrylate)) nanocomposites differing in their nature, size, and surface area were prepared containing one volume percent of silica, alumina or titania. These samples and pure PMMA were prepared in order to analyze how the presence of nanooxides affects the thermal stability and degradation kinetics of the materials. A detailed study of thermal degradation and thermal changes was performed by Simultaneous Thermogravimetry and Differential Scanning Calorimetry (SDT). The proposed mathematical model, including all three heating rates in one minimizing function, well fitted all TGA data obtained with a very high coefficient of correlation. This enabled an assessment of four decomposition steps of the PMMA samples and a calculation of their activation energies and individual contributions to total mass loss. The addition of the largest nanoparticles (titania) caused the highest activation energy for each DTG stage of the PMMA/nanooxide systems. The enhancement of head-to-head H–H bonding strength was achieved by addition of alumina and titania. The influence of the size and nature of nanoparticles on the glass transition temperature of prepared PMMA systems was also determined.

scholarly journals Novel Catalytic Ceramic Conversion Treatment of Ti6Al4V for Improved Tribological and Antibacterial Properties for Biomedical Applications

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6554
Author(s):  
James Alexander ◽  
Huan Dong ◽  
Deepa Bose ◽  
Ali Abdelhafeez Hassan ◽  
Sein Leung Soo ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Biomedical Applications ◽  
Antibacterial Properties ◽  
Oxide Thickness ◽  
The Novel ◽  
X Ray Diffraction ◽  
Wear Factor ◽  
Antibacterial Performance ◽  
Transmission Electron ◽  
Colony Forming Units

Titanium oxide layers were produced via a novel catalytic ceramic conversion treatment (CCCT, C3T) on Ti-6Al-4V. This CCCT process is carried out by applying thin catalytic films of silver and palladium onto the substrate before an already established traditional ceramic conversion treatment (CCT, C2T) is carried out. The layers were characterised using scanning electron microscopy, X-ray diffraction, transmission electron microscopy; surface micro-hardness and reciprocating tribological performance was assessed; antibacterial performance was also assessed with s. aureus. This CCCT has been shown to increase the oxide thickness from ~ 5 to ~ 100 µm, with the production of an aluminium rich layer and agglomerates of silver and palladium oxide surrounded by vanadium oxide at the surface. The wear factor was significantly reduced from ~ 393 to ~ 5 m3/N·m, and a significant reduction in the number of colony-forming units per ml of Staphylococcus aureus on the CCCT surfaces was observed. The potential of the novel C3T treatment has been demonstrated by comparing the performance of C3T treated and untreated Ti6Al4V fixation pins through inserting into simulated bone materials.

scholarly journals Estimation of infection rate and the population size potentially exposed to SARS-CoV-2 in Japan during 2020

2021 ◽  
Author(s):  
Motohiko Naito
Keyword(s):  
Data Analysis ◽  
Infection Rate ◽  
Primary Data ◽  
The Novel ◽  
Primary Data Analysis ◽  
Positive Rate ◽  
Novel Virus ◽  
Definition Of ◽  
Two Peaks ◽  
Domestic Law

AbstractBackgroundThe infectious respiratory disease COVID-19, caused novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reached pandemic status during 2020. The primary statistic data are important to survey the actual circumstances of COVID-19. Here, we report the analysis of the primary data of COVID-19 in Japan during 2020.MethodsData were collected and released systematically under Japan domestic law. Machine learning was conducted to estimate the positive rate in Japan and four prefectures (Tokyo, Osaka, Chiba, and Fukuoka).ResultsPrimary data analysis revealed there were at least two peaks of infection in Japan; the first one was during April 2020 and the second one started from November 1, 2020. Estimating the positive rate in Japan as well as in the four prefectures reinforced the above observations. The positive rate in Japan during 2020 was estimated to be around 6% to 8%. We also estimated that 1.95 million people were possibly exposed to the novel virus on October 31, 2020. The numbers of related deaths were over 3,000 people at the end of 2020.ConclusionWe estimated the infection rate of SARS-CoV-2 in Japan to be 6–8% in 2020. We also concluded that Japan had at least two infection-spreading periods, the first one being from Jan 19, 2020 until May 2020, and the second one beginning from November 1, 2020. Importantly, our analysis supports the need for clear definition of the criteria for conducting confirmation tests before embarking on data analysis.

scholarly journals Development of a Method for the Quantification of Clotrimazole and Itraconazole and Study of Their Stability in a New Microemulsion for the Treatment of Sporotrichosis

Molecules ◽  
2019 ◽  
Vol 24 (12) ◽  
pp. 2333 ◽  
Author(s):  
Patricia Garcia Ferreira ◽  
Carolina Guimarães de Souza Lima ◽  
Letícia Lorena Noronha ◽  
Marcela Cristina de Moraes ◽  
Fernando de Carvalho da Silva ◽  
...  
Keyword(s):  
Benzyl Alcohol ◽  
Hplc Method ◽  
Stability Study ◽  
The Novel ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Sporothrix Brasiliensis ◽  
Accelerated Stability ◽  
New Association ◽  
Analytical Hplc

Sporotrichosis occurs worldwide and is caused by the fungus Sporothrix brasiliensis. This agent has a high zoonotic potential and is transmitted mainly by bites and scratches from infected felines. A new association between the drugs clotrimazole and itraconazole is shown to be effective against S. brasiliensis yeasts. This association was formulated as a microemulsion containing benzyl alcohol as oil, Tween® 60 and propylene glycol as surfactant and cosurfactant, respectively, and water. Initially, the compatibility between clotrimazole and itraconazole was studied using differential scanning calorimetry (DSC), thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FTIR), and X-ray powder diffraction (PXRD). Additionally, a simple and efficient analytical HPLC method was developed to simultaneously determine the concentration of clotrimazole and itraconazole in the novel microemulsion. The developed method proved to be efficient, robust, and reproducible for both components of the microemulsion. We also performed an accelerated stability study of this formulation, and the developed analytical method was applied to monitor the content of active ingredients. Interestingly, these investigations led to the detection of a known clotrimazole degradation product whose structure was confirmed using NMR and HRMS, as well as a possible interaction between itraconazole and benzyl alcohol.

scholarly journals A New Strategy for the Synthesis of Hydroxyl Terminated Polystyrene-b-Polybutadiene-b-Polystyrene Triblock Copolymer with High Cis-1, 4 Content

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 598 ◽  
Author(s):  
Xin Min ◽  
Xiaodong Fan
Keyword(s):  
Triblock Copolymer ◽  
Gel Permeation Chromatography ◽  
Hydroxyl Group ◽  
The Novel ◽  
Scanning Calorimetry ◽  
Gel Permeation ◽  
New Strategy ◽  
Ft Ir ◽  
Novel Catalyst ◽  
Lower Glass Transition Temperature

This work reports the preparation of a hydroxyl terminated polystyrene-b-polybutadiene-b-polystyrene triblock copolymer (SBS) with high cis-1, 4 content via a novel nickel catalyst, [η3-Ni(CH2CHCHCH2OOCH3)][BPhF4]. FT-IR, 1H-NMR, and 13C NMR indicated that the polybutadiene segment of the copolymer contains greater than 90% cis-1, 4 structure, indicating achievement of the objective. Toward the functionalization goal, a hydroxyl group was successfully introduced at the end of the triblock copolymer (HO–SBS–OH). The results of gel permeation chromatography (GPC) revealed that the polymer is indeed a triblock copolymer, with no traces of homopolymer. Differential scanning calorimetry (DSC) showed that HO–SBS–OH synthesized using the novel catalyst had a lower glass transition temperature (Tg) than HO–SBS–OH synthesized with an alkyl lithium catalyst. Therefore, the polymer synthesized via the novel catalyst contains high cis-1,4 content and displays excellent low-temperature mechanical properties.

Physicochemical and Functional Characterisation of Amaranth (Amaranthus hypochondriacus) Protein Isolates Obtained by Isoelectric Precipitation and Micellisation

2005 ◽  
Vol 11 (4) ◽  
pp. 269-280 ◽  
Author(s):  
M. Y. Cordero-de-los-Santos ◽  
J. A. Osuna-Castro ◽  
A. Borodanenko ◽  
O. Paredes-López
Keyword(s):  
Protein Denaturation ◽  
Gel Filtration ◽  
Isoelectric Precipitation ◽  
Scanning Calorimetry ◽  
Protein Isolates ◽  
Amaranthus Hypochondriacus ◽  
Molecular Weights ◽  
Functional Characterisation ◽  
Definition Of ◽  
Two Peaks

Amaranth protein isolates were obtained by two distinct methods, i.e. alkaline extraction-isoelectric precipitation (IP) and micellisation (MP). IP had a greater protein yield (56.4%) and protein content (93.1%) than MP (15.9 and 80.2%, respectively). The gel filtration chromatogram of IP isolates displayed a single peak of ca. 1,380 kDa, whereas MP isolates showed two peaks at 905kDa and 190kDa. A commercial soybean isolate (CSI), analysed for comparison purposes, presented two peaks with molecular weights of 340kDa and 62kDa. Differential scanning calorimetry showed that amaranth isolates were characterised by two endothermic events, predominating in both isolates the second endotherm with a denaturation temperature of 98.7 °C for IP and 97.2 °C for MP. The better definition of MP endotherms and their higher denaturation enthalpy suggested a more homogenous and less denatured protein population, in comparison to IP and CSI. The amaranth isolates had better solubility at alkaline pHs than the CSI. Foaming and emulsification were better at acidic pH for both IP and MP. Colorimetric evaluations showed that the two amaranth isolates had a higher whiteness index than the CSI. In conclusion, extreme pH treatments in IP resulted in a partial protein denaturation and milder treatments in MP resulted in less protein denaturation and improvement of some functional properties.

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