scholarly journals Hybrid system «layered magnesium silicate – chlorin е6 13(1), 17(3)-N,N'-(2-hydroxyethyl)diamide 15(2)-methyl ester»

2019 ◽  
Vol 58 (4) ◽  
pp. 34-39
Author(s):  
Inna V. Loukhina ◽  
◽  
Irina S. Khudyaeva ◽  
Anna Yu. Bugaeva ◽  
Dmitry V. Belykh ◽  
...  

Hectorite type layered magnesium silicate have been synthesized by heat treatment of reaction mixture freshly prepared magnesium hydroxide suspension, silica sol, lithium fluoride solution. The starting Mg(OH)2 : SiO2 : LiF molar ratio was 1 : 1.51 : 0.25. Hybrid systems have been synthesized by heat treatment of synthetic layered magnesium silicate in water-ethanol solution of chlorin е6 13 (1), 17(3)-N,N'-(2-hydroxyethyl) diamide 15(2)-methyl ester. The systems contain of 0.85∙10-6 and 1.4∙10-6mol of the organic component per 1 g of layered magnesium silicate. The introduction of the chlorin e6 derivative into hectorite type layered magnesium silicate sol promotes the aggregation processes and growth particles of the hybrid samples (250±5 nm), as compared with the particles of magnesium silicate (133±1 nm). X-ray phase analysis, UV-Vis spectroscopy and laser Doppler electrophoresis studies have been allowed to establish that non-aggregated molecules of the chlorin e6 derivative are located on the surface of magnesium silicate particles.UV-Vis spectroscopy study showed protonation of nitrogen atoms of the chlorine macrocycle of the chlorin e6 derivative molecules (Soret band 405-406 nm; Q-band 642-643 nm) by hydroxyl groups of the layered magnesium silicate. Chlorin е6 13 (1), 17(3)-N,N'-(2-hydroxyethyl) diamide 15(2)-methyl ester sorption on the surface of magnesium silicate particles occurs due to electrostatic interaction between protonated chlorine e6 derivative molecules and ionized hydroxyl groups of the magnesium silicate.

2020 ◽  
Vol 62 (4) ◽  
pp. 12-18
Author(s):  
Inna V. Loukhina ◽  

Matrices based on layered silicates have a set of useful properties, in particular, they are able to increase the stability and photosensitizing ability of porphyrins. Hybrid systems “layered silicate - porphyrin (metal porphyrin)” are promising as active components of systems for light collecting and artificial photosynthesis, catalysts, photocatalysts. The hybrid systems with content of 1.4∙10-6 and 4.2∙10-6 mol of the chlorin e6 13(1),15(2),17(3)-N,N',N''-(2-hydroxyethyl)triamide per 1 g of layered magnesium silicate was obtained by heat treatment method of a synthetic layered magnesium silicate of hectorite composition when treated with an aqueous-alcoholic solution of organic component. The molar ratio of the starting components is: Mg(OH)2 : SiO2 : LiF = 1 : 1.51 : 0.25 : chlorin e6 derivative = 1 : 1.51 : 0.25 : (19.93∙10-5 – 59.58∙10-5). Using dynamic light scattering and laser Doppler electrophoresis, it was shown that the introduction of chlorin e6 13(1),15(2),17 (3)-N,N',N''- (2-hydroxyethyl) triamide leads to the growth of hybrid particles (162 ± 3 nm) and a decrease in their aggregative stability (-30 ± 1 mV), compared with the initial layered magnesium silicate (133 ± 1 nm, -33 ± 1 mV). In this case, the introduction of more hydrophilic chlorin e6 13(1),15(2),17(3)-N,N',N''-(2-hydroxyethyl)triamidе, in the molecule of which there are three fragments of ethanolamine, allows to obtain smaller hybrid particles (162 ± 3 nm), compared with hybrid particles (248 ± 6 nm) formed by the action of chlorin e6 13(1),17(3)-N,N'-(2-hydroxyethyl)diamide15(2)-methyl ether, in the molecule of which there are two fragments of ethanolamine. Using the methods of X-ray phase analysis and electron spectroscopy in the UV-visible region, it was found that individual molecules of chlorin e6 13(1),15(2),17(3)-N,N',N''-(2-hydroxyethyl)triamide were sorbed on the surface of silicate particles due to the electrostatic interaction between the protonated molecules of the macrocycle and the ionized hydroxyl groups of magnesium silicate. It was shown that the higher hydrophilicity of chlorin e6 13(1),15(2),17(3)-N,N',N''-(2-hydroxyethyl)triamide, compared with chlorin e6 13(1),17(3)-N,N'-(2-hydroxyethyl)diamide15(2)-methyl ether did not contribute to the intercalation of the organic component into the interlayer space of layered magnesium silicate under the conditions of a water-alcohol medium.


2013 ◽  
Vol 634-638 ◽  
pp. 2301-2306 ◽  
Author(s):  
Qi An Zhu ◽  
Yao Wu ◽  
Xu Feng Sun ◽  
Xian Tan ◽  
Kai Zhan ◽  
...  

Barium strontium titanate nano powders were prepared by mixing ethanol solution of tetrabutyl titanate with an aqueous solution of Ba(OH)2•8H2O and Sr(OH)2•8H2O with a certain molar ratio of barium to strontium at 40°C-95°C. The products were characterized by thermogravimetry (TG), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), transmission electron microscope (TEM) and atomic force microscopy (AFM). The results show that the powders prepared with the reactant concentration of 0.8M are spherical in particle shape with the grain size of 50nm-65nm. When the annealing temperature of the powders is higher than 906°C, the hydroxyl groups existed in barium strontium titanate lattice are removed. XRD analysis demonstrate that the as-prepared powders are cubic phase. All the diffraction peaks are shifted towards higher diffraction angles and the lattice parameter a calculated decreases linearly with serial decrease of the molar ratio of barium to strontium.


Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1869
Author(s):  
A K M Mashud Alam ◽  
Donovan Jenks ◽  
George A. Kraus ◽  
Chunhui Xiang

Organophosphate (OP) compounds, a family of highly hazardous chemical compounds included in nerve agents and pesticides, have been linked to more than 250,000 annual deaths connected to various chronic diseases. However, a solid-state sensing system that is able to be integrated into a clothing system is rare in the literature. This study aims to develop a nanofiber-based solid-state polymeric material as a soft sensor to detect OP compounds present in the environment. Esters of polydiacetylene were synthesized and incorporated into a cellulose acetate nanocomposite fibrous assembly developed with an electrospinning technique, which was then hydrolyzed to generate more hydroxyl groups for OP binding. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), Instron® tensile tester, contact angle analyzer, and UV–Vis spectroscopy were employed for characterizations. Upon hydrolysis, polydiacetylene esters in the cellulosic fiber matrix were found unaffected by hydrolysis treatment, which made the composites suitable for OP sensing. Furthermore, the nanofibrous (NF) composites exhibited tensile properties suitable to be used as a textile material. Finally, the NF composites exhibited colorimetric sensing of OP, which is visible to the naked eye. This research is a landmark study toward the development of OP sensing in a protective clothing system.


2014 ◽  
Vol 660 ◽  
pp. 297-300
Author(s):  
Nor Hazwani Abdullah ◽  
Sulaiman Hassan

Waste cooking oil has always been an environment problem in food factories and one method of effect disposing this oil without effecting the environment is to convert it to fatty acid methyl ester (FAME) using small scale pilot plant. The conversion of waste cooking oil with sodium hydroxide as a catalyst in conversional process at 22kHz speed. The reaction of time, molar ratio, speed, catalyst and amount of catalyst will be effect in FAME quality. The quality of biodiesel define is total ester content using gas chromatography. Gas chromatography analysis is a one of technique for identification and quantitation of compounds in a biodiesel sample. From biodiesel sample can identification of contaminants and fatty acid methyl ester. In this research biodiesel sample were analyses using a gas chromatography-flame ionization detector ( Perkin Elmer GC Model Clarus 500) equipped with a DB-5 HT capillary column ( 0.53mm x 5 m) J&W Scientific. The analytic conditions for ester content were as follow by: column temperature used 2100C, temperature flame ionization detector (FID) of 2500C, pressure of 80kPa, flow carrier gas of 1ml/min, temperature injector of 2500C, split flow rate of 50ml/min, time for analysis 20 minute and volume injected of 1 μl. The ester content (C), expresses as a mass fraction in present using formula (EN 14103, 2003a) calculation. Conversion of triglyceride (TG) to FAME using conversional process obtained 96.54 % w.t with methanol to oil molar ratio 6:1, 1%w.t acid sulphuric and 1% w.t sodium hydroxide catalyst.


2014 ◽  
Vol 554 ◽  
pp. 500-504 ◽  
Author(s):  
Farid Nasir Ani ◽  
Ahmed Bakheit Elhameed

This paper investigated the three critical reaction parameters including catalyst concentration, microwave exit power and reaction time for the transesterification process of jatropha curcas oil using microwave irradiation. The work is an attempt to reduce the production cost of biodiesel. Similar quantities of methanol to oil molar ratio 6:1 and calcium oxide as a heterogeneous catalyst were used. The results showed that the best yield percentage 96% was obtained using 300W microwave exit power, 8 %wt CaO and 7 min. The methyl ester FAME obtained was within the standard of biodiesel fuel.


2008 ◽  
Vol 5 (2) ◽  
pp. 285-296
Author(s):  
Baghdad Science Journal

A new Schiff base o-hydroxybenzylidene-1-phenyl-2,3-dimethyl-4-amino-3-pyrazolin-5-on (HL) ,have been prepared and characterization.(HL) has been used as a chelating ligand to prepare a number of metal complexes VO(II) ,Cr(III) ,Mn(II),Fe(II),Hg(II) and UO2(II) .and mixed ligands complexes have been prepared between o-hydroxybenzylidene-1-phenyl-2,3-dimethyl-4-amino-3-pyrazolin-5-on and 8- hydroxy quinoline with VO(II),Zn(II),Cd(II), Hg(II) and UO2(II) the prepared complexes were isolated and characterized by (FT-IR)and (UV-Vis) spectroscopy. Elemental analysis (C.H.N) Chloride contents, Flame atomic absorption technique. in addition to magnetic susceptibility and conductivity measurement. Molar ratio measurement in solution gave comparable results with those obtained from solid state study.


2019 ◽  
Vol 85 (3) ◽  
pp. 3-19
Author(s):  
Polina Borovyk ◽  
Mariia Litvinchuk ◽  
Anton Bentya ◽  
Svitlana Orysyk ◽  
Yurii Zborovskiy ◽  
...  

The possibility of using N-allylcarbothioamide derivatives as well as products of their iodine- and proton-initiated electrophilic heterocyclizations as chelating agents in complexation reactions with Zn(II) and Ag(I) ions is shown. Processing of the obtained experimental data showed that N-allythioamides of pyrimidinyl (cyclohexenyl) carboxylic acids H2L1 – H2L3 and their proton- and iodo-cyclization products HL4, HL5 containing four nucleophilic reaction centers (two oxygen atoms of the carbonyl and hydroxyl groups and N-, S-carbothioamide groups or N-atoms of the dihydrothiazole moiety) are polydentate ligands capable of coordinating with metal ions to form stable six-membered chelate metallocycles. A series of new chelating mono-, bi- and polynuclear complexes Zn(II) and Ag (I) of the composition [Zn2L1,32]n, [Zn2(HL1-3)2(CH3COO)2], [Ag2(HL1,3)2]n, [Zn(HL1-3)2], [Ag(H2L3)2NO3], [Zn(HL4,5)2], K[Ag(HL4,5)2] were synthesized and isolated in solid state. Their molecular structure was established by methods of elemental chemical analysis, NMR 1H, IR and UV-Vis spectroscopy. At a ratio of M:L 1:2, complexes were isolated in which two ligand molecules H2L1 − H2L3 are coordinated to the metal ion by the sulfur atoms of the carbothioamide group and the oxygen of the mono-deprotonated hydroxyl group. It was established that the products of the proton-/iodocyclization HL4, HL5 in the complex formation pass into the thione tautomeric form with coordination through the oxygen atoms of the deprotonated hydroxyl group and nitrogen atoms of the dihydrothiazole heterocycle. At M:L 1:1, binuclear or polynuclear coordination compounds are formed. It was shown that polymerisation in complexes [Zn2L1,32]n and [Ag2(HL1,3)2]n is due to the formation of Zn−(O2SN)−Zn and Ag−O−Ag polymer chains. Investigation of the solubility of the resulting complexes showed that the polymer complexes are weakly soluble or insoluble in DMSO, DMF, while the mononuclear are soluble in methanol, as well as in water.


2021 ◽  
Vol 55 (6) ◽  
Author(s):  
Trung Kien Pham ◽  
Tran Ngo Quan

In this paper, we report on synthesizing xonotlite, calcium silicate hydrate (CSH), via a hydrothermal reaction using rice husk from the Mekong Delta, Vietnam. The rice husks were burnt at 1000 °C for 3 h. Grey rice husk ash was collected, then mixed with Ca(OH)2 at a Ca/Si molar ratio of 1 : 1. This was followed by a hydrothermal reaction at 180 °C for 24 h and 48 h to obtain the xonotlite mineral. Before and after adsorption, 3-mm xonotlite pellets were thoroughly characterized using X-ray diffractometry (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and ultraviolet-visible (UV-VIS) spectroscopy. This material has potential application in chromium(III) removal during a chrome-plating process. The adsorption efficiency of the 3-mm pellet samples reached more than 76 % after 12 h.


2018 ◽  
Vol 1 (4) ◽  
pp. e00063 ◽  
Author(s):  
V.N. Prozorovskiy ◽  
L.V. Kostryukova ◽  
E.I. Korotkevich ◽  
T.I. Torkhovskaya ◽  
G.E. Morozevich ◽  
...  

The possibility of increased internalization of the photosensitizer chlorin e6 in tumor cells was investigatedusing soy phosphatidylcholine nanoparticles 20-30 nm with or without attached peptide containing Asn-Gly-Arg (NGR) motif was studied. This amino acid sequence exhibits affinity to aminopeptidase N (CD13), wich is overexpressed in a number of tumor cells and vessels. Nanoparticles with chlorin e6 were prepared with added of distearoylphosphatidylcholine (DSPE) conjugated through PEG with a hexapeptide containing the NGR sequence, and then were incubated with tumor cells НерG2 and MCF-7. Chlorin e6 accumulation in СD13-negative cells (MCF-7) did not depend on the presence of peptide NGR in nanoparticles. However, for НерG2 cells a twofold increase of chlorine e6 internalization was observed as compared with the same particles without NGR. Differences in the response of these two cell lines, differed in expression of aminopeptidase N (APN), suggest the possibility of this protein using for targeted delivery. The prospectivity of usage of phospholipids nanoparticles conjugated with targeting peptide for photodynamic therapy is discussed, taking into account possible variation of APN expression, inherent for many solid tumors.


2014 ◽  
Vol 787 ◽  
pp. 35-40 ◽  
Author(s):  
Xiao Yan Zhou ◽  
Peng Wei Zhou ◽  
Hao Guo ◽  
Bo Yang ◽  
Ru Fei Ren

The p-n junction photocatalysts, p-CuO (at. 0-25%)/n-ZnO nanocomposite were prepared through hydrothermal method without using any organic solvent or surfactant. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-Ray spectroscopy, and UV-vis spectroscopy. The results demonstrated that the CuO/ZnO nanocomposite presented a two-dimensional morphology composed of sheet-like ZnO nanostructures adorned with CuO nanoparticles. The photocatalytic activity of CuO/ZnO with different Cu/Zn molar rations and pure ZnO synthesized by the identical synthetic route were evaluated by degrading methylene blue (MB) dye under UV-visible light irradiation. The CuO/ZnO with Cu/Zn molar ratio of 4% exhibits the highest photocatalytic activity compared that of the other photocatalysts under the identical conditions. It is mainly attributed to the increased charge separation rate in the nanocomposite and the extended photo-responding range.


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