The present study was designed to examine the chemical composition and the antioxidant activity of Bunium incrassatum extracts prepared in five different solvents with increasing polarities. RP-HPLC analysis resulted in the identification of 12 phenolic compounds, including 8 phenolic acids (caffeic acid, ellagic acid, ferulic acid, gallic acid, rosmarinic acid, sinapic acid, syringic acid, and vanillic acid) and 4 flavonoids (catechin, hesperetin, luteolin, and quercetin). Two different test systems were used to assess the antioxidant activity: DPPH and β-carotene/linoleic acid assays. Methanol extract exhibited the highest DPPH scavenging potential and even low inhibitory effect against β-carotene bleaching, whereas chloroform extract showed the highest effect against β-carotene bleaching and a weak scavenging potential. As expected, methanol extract recorded the highest content of total phenolics (26.57±0.15 mg GAE/g E), while chloroform extract has been found to be the richest in flavonoids.
{"title":"Comparison of Major Bioactive Components of Various Solvent Extracts from Algerian Bunium incrassatum Umbellules and Antioxidant Activity","authors":"F. Toul, Amina Djendar","doi":"10.18596/jotcsa.1184342","DOIUrl":"https://doi.org/10.18596/jotcsa.1184342","url":null,"abstract":"The present study was designed to examine the chemical composition and the antioxidant activity of Bunium incrassatum extracts prepared in five different solvents with increasing polarities. RP-HPLC analysis resulted in the identification of 12 phenolic compounds, including 8 phenolic acids (caffeic acid, ellagic acid, ferulic acid, gallic acid, rosmarinic acid, sinapic acid, syringic acid, and vanillic acid) and 4 flavonoids (catechin, hesperetin, luteolin, and quercetin). Two different test systems were used to assess the antioxidant activity: DPPH and β-carotene/linoleic acid assays. Methanol extract exhibited the highest DPPH scavenging potential and even low inhibitory effect against β-carotene bleaching, whereas chloroform extract showed the highest effect against β-carotene bleaching and a weak scavenging potential. As expected, methanol extract recorded the highest content of total phenolics (26.57±0.15 mg GAE/g E), while chloroform extract has been found to be the richest in flavonoids.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81671527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the present study, the electroanalytical behavior of 17β-estradiol was investigated using cyclic voltammetry. The procedure was based on 17β-estradiol being electrochemically oxidized at a platinum electrode in non-aqueous solutions. At 1.47 V, the oxidation peak was noted. It was discovered that 17β-estradiol's oxidation was diffusion-controlled. Additionally, a quick and easy square wave voltammetry method was developed and validated in this work to determine 17β-estradiol in pharmaceutical preparations. The calibration curve was linear at 5 and 30 µg/mL concentrations. The precision was given by relative standard deviation and was less than 3.36%. Accuracy was given with relative error and did not exceed 2.54%. In pharmaceutical preparations, 17β-estradiol had an average recovery of 100.3%. Under the chosen experimental conditions, no interference was found. The suggested method is highly accurate and precise. Therefore, the method applies to measuring 17β-estradiol in pharmaceutical formulations.
{"title":"Electrochemical Study of 17β-Estradiol and its Determination in Pharmaceutical Preparations using Square Wave Voltammetry","authors":"B. Yılmaz, Y. Kadioglu","doi":"10.18596/jotcsa.1288155","DOIUrl":"https://doi.org/10.18596/jotcsa.1288155","url":null,"abstract":"In the present study, the electroanalytical behavior of 17β-estradiol was investigated using cyclic voltammetry. The procedure was based on 17β-estradiol being electrochemically oxidized at a platinum electrode in non-aqueous solutions. At 1.47 V, the oxidation peak was noted. It was discovered that 17β-estradiol's oxidation was diffusion-controlled. Additionally, a quick and easy square wave voltammetry method was developed and validated in this work to determine 17β-estradiol in pharmaceutical preparations. The calibration curve was linear at 5 and 30 µg/mL concentrations. The precision was given by relative standard deviation and was less than 3.36%. Accuracy was given with relative error and did not exceed 2.54%. In pharmaceutical preparations, 17β-estradiol had an average recovery of 100.3%. Under the chosen experimental conditions, no interference was found. The suggested method is highly accurate and precise. Therefore, the method applies to measuring 17β-estradiol in pharmaceutical formulations.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73534775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this work, a high solids acrylic copolymer polyol (poly(MMA/BA/HEMA/AA)) was synthesized from the polymerization of methyl methacrylate (MMA), butyl acrylate (BA), hydroxyethyl methacrylate (HEMA) and acrylic acid (AA) and was added to the polyaspartic resin. The polyaspartic-polyol mixtures reacted with polyisocyanates to create hybrid polyurethane-polyaspartic hybrid coatings. Different amounts of synthesized acrylic copolymer (5, 10, and 20% of total resin mixture) were mixed into polyaspartic resin and subsequently reacted with polyisocyanates in a 1:1 molar ratio. The characterization of the polymer was performed with Gel Permeation Chromatography (GPC), Fourier-Transform Infrared-Attenuated Total Reflection (FTIR-ATR) and Differential Scanning Calorimetry (DSC). The determination of physical and mechanical properties of the hybrid coatings was accomplished by hardness, glossiness, abrasion, stress-strain, corrosion, and impact tests. The results indicated that by adding high solids acrylic copolymer (HSAC), the drawbacks of polyaspartic resin (short pot life, hardness and brittleness, and poor adhesiveness) have been largely eliminated without reducing its intrinsic properties. The pot life increased from 16 minutes to 27 minutes and shore D hardness decreased from 60-65 to 52-55 as the polyol content increased in the mixtures. The acrylic polyols and aspartic mixtures may be used in the preparation of paints and varnishes applied on concrete, metal, and wood surfaces.
{"title":"Preparation and Characterization of Polyaspartic and a High Solids Acrylic Copolymer Polyol Based Polyurethanes","authors":"Cemil Dizman, Elif Cerrahoğlu Kaçakgil, Levent Babayi̇ği̇t, Caner Arar","doi":"10.18596/jotcsa.1216320","DOIUrl":"https://doi.org/10.18596/jotcsa.1216320","url":null,"abstract":"In this work, a high solids acrylic copolymer polyol (poly(MMA/BA/HEMA/AA)) was synthesized from the polymerization of methyl methacrylate (MMA), butyl acrylate (BA), hydroxyethyl methacrylate (HEMA) and acrylic acid (AA) and was added to the polyaspartic resin. The polyaspartic-polyol mixtures reacted with polyisocyanates to create hybrid polyurethane-polyaspartic hybrid coatings. Different amounts of synthesized acrylic copolymer (5, 10, and 20% of total resin mixture) were mixed into polyaspartic resin and subsequently reacted with polyisocyanates in a 1:1 molar ratio. The characterization of the polymer was performed with Gel Permeation Chromatography (GPC), Fourier-Transform Infrared-Attenuated Total Reflection (FTIR-ATR) and Differential Scanning Calorimetry (DSC). The determination of physical and mechanical properties of the hybrid coatings was accomplished by hardness, glossiness, abrasion, stress-strain, corrosion, and impact tests. The results indicated that by adding high solids acrylic copolymer (HSAC), the drawbacks of polyaspartic resin (short pot life, hardness and brittleness, and poor adhesiveness) have been largely eliminated without reducing its intrinsic properties. The pot life increased from 16 minutes to 27 minutes and shore D hardness decreased from 60-65 to 52-55 as the polyol content increased in the mixtures. The acrylic polyols and aspartic mixtures may be used in the preparation of paints and varnishes applied on concrete, metal, and wood surfaces.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86922871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A novel and green photochemical polymerization method of N-methylpyrole is reported. Spectral and chromatographic characterizations revealed the formation of high molecular weight polymer (1436 kg/mol) having light absorption in the near-infrared region (~750 nm), high fluorescence emission in the visible region, high conductivity (0.062 S/cm) and good thermal stability. Powder X-ray diffractogram identified a totally amorphous polymer. According to cyclic voltammetry studies the polymer formed (PMPy) possess a relatively low electronic band gap (1.39 eV) which is very important for the (opto)electronic device applications of such materials.
{"title":"Photoproduction of High Molecular Weight Poly (N-methylpyrrole) under Green Conditions","authors":"Kerem Kaya","doi":"10.18596/jotcsa.1232989","DOIUrl":"https://doi.org/10.18596/jotcsa.1232989","url":null,"abstract":"A novel and green photochemical polymerization method of N-methylpyrole is reported. Spectral and chromatographic characterizations revealed the formation of high molecular weight polymer (1436 kg/mol) having light absorption in the near-infrared region (~750 nm), high fluorescence emission in the visible region, high conductivity (0.062 S/cm) and good thermal stability. Powder X-ray diffractogram identified a totally amorphous polymer. According to cyclic voltammetry studies the polymer formed (PMPy) possess a relatively low electronic band gap (1.39 eV) which is very important for the (opto)electronic device applications of such materials.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79435702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Zi̇yaev, S. Sasmakov, T. Toshmurodov, M. Ziyaeva, J. Abdurakhmanov, S. Khasanov, Shakhnoza S. Azimova
The S-(5-aryl-1,3,4-oxadiazol-2-yl) O-alkyl carbonothioate (4-9) and the alkyl 2-((5-aryl-1,3,4-oxadiazol-2-yl)thio) acetate (10-15) were synthesized by interaction of 5-aryl-1,3,4-oxadiazole-2-thiones with alkyl esters of chloroformic acid and chloroacetic acid. The yields of target compounds (7-9) obtained with isobutyl chloroformate were 69-73%, compounds (4-6) with propyl chloroformate - 74-79% and compounds (10-15) with alkyl esters of chloroacetic acid - 86-92%, respectively. The structures of the synthesized compounds were confirmed by IR, UV, 1H and 13C NMR spectra. The antibacterial and antifungal activities of these compounds were investigated. The results of in vitro antimicrobial activity tests showed that S-(5-phenyl(2-chlorophenyl)-1,3,4-oxadiazol-2-yl) O-propyl carbonothioate (4-5) and S-(5-phenyl(2-chlorophenyl)-1,3,4-oxadiazol-2-yl) O-isobutyl carbonothioate (7-8) exhibited weak, but selective antibacterial activity against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus). At the same time, no activity was shown by compounds with two chlorine atoms in the aromatic ring (13-15) and alkyl 2-((5-aryl-1,3,4-oxadiazol-2-yl) thio) acetate (10-15).
{"title":"Synthesis of S-(5-aryl-1,3,4-oxadiazol-2-yl) O-alkyl carbonothioate and alkyl 2-((5-aryl-1,3,4-oxadiazol-2-yl)thio) acetate, and their antimicrobial properties","authors":"A. Zi̇yaev, S. Sasmakov, T. Toshmurodov, M. Ziyaeva, J. Abdurakhmanov, S. Khasanov, Shakhnoza S. Azimova","doi":"10.18596/jotcsa.1250629","DOIUrl":"https://doi.org/10.18596/jotcsa.1250629","url":null,"abstract":"The S-(5-aryl-1,3,4-oxadiazol-2-yl) O-alkyl carbonothioate (4-9) and the alkyl 2-((5-aryl-1,3,4-oxadiazol-2-yl)thio) acetate (10-15) were synthesized by interaction of 5-aryl-1,3,4-oxadiazole-2-thiones with alkyl esters of chloroformic acid and chloroacetic acid. The yields of target compounds (7-9) obtained with isobutyl chloroformate were 69-73%, compounds (4-6) with propyl chloroformate - 74-79% and compounds (10-15) with alkyl esters of chloroacetic acid - 86-92%, respectively. The structures of the synthesized compounds were confirmed by IR, UV, 1H and 13C NMR spectra. The antibacterial and antifungal activities of these compounds were investigated. The results of in vitro antimicrobial activity tests showed that S-(5-phenyl(2-chlorophenyl)-1,3,4-oxadiazol-2-yl) O-propyl carbonothioate (4-5) and S-(5-phenyl(2-chlorophenyl)-1,3,4-oxadiazol-2-yl) O-isobutyl carbonothioate (7-8) exhibited weak, but selective antibacterial activity against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus). At the same time, no activity was shown by compounds with two chlorine atoms in the aromatic ring (13-15) and alkyl 2-((5-aryl-1,3,4-oxadiazol-2-yl) thio) acetate (10-15).","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76897576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The reaction of low-temperature oxidation of carbon monoxide is important in the context of air purification and reduction of automotive emissions. Along with the search for active catalytic systems for carbon monoxide oxidation, the development of new energy-saving methods of catalyst synthesis also seems important. Cobalt-iron, cobalt-manganese, cobalt-chromium, cobalt-copper binary and cobalt-manganese-iron, cobalt-copper-iron-containing triple oxide systems for low-temperature oxidation of carbon monoxide into carbon dioxide were synthesized by the sol-gel method with auto-combustion. The samples were analyzed by X-ray diffraction, IR spectral and derivatographic methods of analysis, their specific surface area was measured by the BET method, micro-photographs were taken on a scanning electron microscope. It was established that the resulting binary and ternary cobalt-containing oxide systems are multiphase systems containing ferrites, manganites, and oxides of cobalt, copper, manganese, and iron. The resulting catalysts are active in the low-temperature oxidation of carbon monoxide at 145-180 °C. The activation energy of the CO oxidation reaction on the analyzed oxide systems was revealed by the Arrhenius equation is placed in the range of 17-33 kJ/mol. In the systems, an intensifying effect of the influence of its components on the catalytic activity is observed in the oxide and spinel phases. The Co-Cr=2:1 system, which, along with chromite, also contains cobalt oxide, which is active at a much lower temperature – 145 °C than systems with a Co-Cr=1:1 and 1:2 ratios. A similar dependence was obtained in the Co-Fe=2:1 system, i.e. in a sample that, along with cobalt ferrite, also contains cobalt oxide. On this catalyst, 100% conversion of CO to CO2 occurs at a temperature of 200 °C, and a Co-Fe = 1:2 sample with a stoichiometric ratio of metals, in which the ferritization reaction completely occurs, as experiments have shown, is active only at temperatures above 300 °C. The intensifying effect of the influence of the components on its activity is also observed in three-component systems, in which the complete conversion of CO occurs at a temperature of 145-160 °C. The appearance of various structural defects during short-term combustion of the gel without additional heat treatment, which can potentially be considered as catalytically active centers, on the one hand, and the presence of oxide and spinel phases in the composition of catalysts, which exhibit a mutual reinforcing effect, on the other hand, is demonstrative advantage of this method for the synthesis of active catalysts for low-temperature oxidation of carbon monoxide to dioxide.
一氧化碳低温氧化反应在空气净化和减少汽车尾气排放方面具有重要意义。随着对一氧化碳氧化活性催化系统的研究，开发新的节能催化剂合成方法也显得很重要。采用自燃烧的溶胶-凝胶法制备了低温氧化一氧化碳成二氧化碳的钴铁、钴锰、钴铬、钴铜二元和钴锰铁、钴铜铁三元氧化物体系。采用x射线衍射、红外光谱和衍生分析法对样品进行了分析，采用BET法测量了样品的比表面积，并在扫描电子显微镜下拍摄了显微照片。确定了二元和三元含钴氧化物体系是含铁氧体、锰酸盐以及钴、铜、锰和铁的氧化物的多相体系。所制得的催化剂在145 ~ 180℃的一氧化碳低温氧化反应中具有活性。根据Arrhenius方程，所分析的氧化体系中CO氧化反应的活化能在17 ~ 33kj /mol之间。在该体系中，氧化相和尖晶石相的组分对催化活性的影响越来越大。Co-Cr=2:1的体系，与铬铁矿一起，还含有氧化钴，它在145°C的温度下具有活性，比Co-Cr=1:1和1:2的体系低得多。在Co-Fe=2:1体系中也获得了类似的依赖关系，即在样品中，除了钴铁氧体，还含有钴氧化物。在该催化剂上，CO在200℃的温度下100%转化为CO2，而CO - fe = 1:2的金属化学计量比样品中，铁化反应完全发生，实验表明，只有在300℃以上的温度下才有活性。在三组分体系中，CO的完全转化发生在145-160℃的温度下，组分对其活性的影响也在增强。在没有额外热处理的情况下，凝胶在短期燃烧过程中出现的各种结构缺陷，一方面可能被认为是催化活性中心，另一方面，催化剂组成中存在氧化物和尖晶石相，它们表现出相互增强的作用，这表明该方法在合成一氧化碳低温氧化成二氧化碳的活性催化剂方面具有优势。
{"title":"Cobalt-Containing Oxide Catalysts Obtained by The Sol-Gel Method with Auto-Combustion in The Reaction of Low-Temperature Oxidation of Carbon Monoxide","authors":"S. Zulfugarova","doi":"10.18596/jotcsa.1261839","DOIUrl":"https://doi.org/10.18596/jotcsa.1261839","url":null,"abstract":"The reaction of low-temperature oxidation of carbon monoxide is important in the context of air purification and reduction of automotive emissions. Along with the search for active catalytic systems for carbon monoxide oxidation, the development of new energy-saving methods of catalyst synthesis also seems important. Cobalt-iron, cobalt-manganese, cobalt-chromium, cobalt-copper binary and cobalt-manganese-iron, cobalt-copper-iron-containing triple oxide systems for low-temperature oxidation of carbon monoxide into carbon dioxide were synthesized by the sol-gel method with auto-combustion. The samples were analyzed by X-ray diffraction, IR spectral and derivatographic methods of analysis, their specific surface area was measured by the BET method, micro-photographs were taken on a scanning electron microscope. It was established that the resulting binary and ternary cobalt-containing oxide systems are multiphase systems containing ferrites, manganites, and oxides of cobalt, copper, manganese, and iron. The resulting catalysts are active in the low-temperature oxidation of carbon monoxide at 145-180 °C. The activation energy of the CO oxidation reaction on the analyzed oxide systems was revealed by the Arrhenius equation is placed in the range of 17-33 kJ/mol. In the systems, an intensifying effect of the influence of its components on the catalytic activity is observed in the oxide and spinel phases. The Co-Cr=2:1 system, which, along with chromite, also contains cobalt oxide, which is active at a much lower temperature – 145 °C than systems with a Co-Cr=1:1 and 1:2 ratios. A similar dependence was obtained in the Co-Fe=2:1 system, i.e. in a sample that, along with cobalt ferrite, also contains cobalt oxide. On this catalyst, 100% conversion of CO to CO2 occurs at a temperature of 200 °C, and a Co-Fe = 1:2 sample with a stoichiometric ratio of metals, in which the ferritization reaction completely occurs, as experiments have shown, is active only at temperatures above 300 °C. The intensifying effect of the influence of the components on its activity is also observed in three-component systems, in which the complete conversion of CO occurs at a temperature of 145-160 °C. The appearance of various structural defects during short-term combustion of the gel without additional heat treatment, which can potentially be considered as catalytically active centers, on the one hand, and the presence of oxide and spinel phases in the composition of catalysts, which exhibit a mutual reinforcing effect, on the other hand, is demonstrative advantage of this method for the synthesis of active catalysts for low-temperature oxidation of carbon monoxide to dioxide.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88394803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The behavior of two porphyrin compounds, meso-tetra-p-tolylporphyrin (TTPH2) and meso-tetra-naphthylporphyrin (TNPH2) was studied and monitored during their adsorption on cation-exchanged montmorillonite clay (MMT). When these two compounds were reacted with MMT, the visible absorption spectra showed a clear shift of 10 nm higher than that found in the acetic acid solution. This suggests that the two compounds prefer to be more planar on the clay surface and, in the case of TTPH2, in the MMT interlamellar layers. The basal spacing of the MMT was increased by 4.4 Å when the TTPH42+ cations entered the spacers. The metal-exchanged ion in the clay is incorporated into the porphyrin rings when the TTPH2 and TNPH2 molecules react with MMT saturated with the metal ion of an appropriate size to fit in the porphyrin ring, such as Cu(II). The process occurred when executed in a solvent miscible with water that allowed the penetration of the hydrated sphere of the metal ion. Metalloporphyrin complexes are formed as a result of this process. The reactions were monitored using visible absorption spectra, diffuse reflectance spectra, x-ray diffraction, infrared spectra, and electron microscopy.
{"title":"Adsorption of the Meso-Tetra-p-Tolylporphyrin (TTPH2) and Meso-Tetra-Naphthylporphyrin (TNPH2) onto Montmorillonite","authors":"J. Hassen, J. Silver","doi":"10.18596/jotcsa.1224193","DOIUrl":"https://doi.org/10.18596/jotcsa.1224193","url":null,"abstract":"The behavior of two porphyrin compounds, meso-tetra-p-tolylporphyrin (TTPH2) and meso-tetra-naphthylporphyrin (TNPH2) was studied and monitored during their adsorption on cation-exchanged montmorillonite clay (MMT). When these two compounds were reacted with MMT, the visible absorption spectra showed a clear shift of 10 nm higher than that found in the acetic acid solution. This suggests that the two compounds prefer to be more planar on the clay surface and, in the case of TTPH2, in the MMT interlamellar layers. The basal spacing of the MMT was increased by 4.4 Å when the TTPH42+ cations entered the spacers. The metal-exchanged ion in the clay is incorporated into the porphyrin rings when the TTPH2 and TNPH2 molecules react with MMT saturated with the metal ion of an appropriate size to fit in the porphyrin ring, such as Cu(II). The process occurred when executed in a solvent miscible with water that allowed the penetration of the hydrated sphere of the metal ion. Metalloporphyrin complexes are formed as a result of this process. The reactions were monitored using visible absorption spectra, diffuse reflectance spectra, x-ray diffraction, infrared spectra, and electron microscopy.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80905772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Unfortunately, many toxic solvents are used in chemistry laboratories and in the manufacturing of materials, which poses a serious risk to process safety, the natural environment, and human health. In this review, different tools for solvent-free organic reactions have been surveyed as an approach for green chemistry, where many of the solvents are known to upset our ecosystems so an enormous research effort has been exerted during the last decade to avoid the utilization of hazardous solvents and the number of publications on solvent-free reactions has increased nearly exponentially. Obviously, this reflects the great interest in solventless reactions. In our survey, we will highlight the solvent-free organic reaction as an approach for green chemistry to cover work published up to nearly 2022.
{"title":"Solvent-free Organic Reaction Techniques as an Approach for Green Chemistry","authors":"A. Youni̇s, Anwar Faizd Osman","doi":"10.18596/jotcsa.1188983","DOIUrl":"https://doi.org/10.18596/jotcsa.1188983","url":null,"abstract":"Unfortunately, many toxic solvents are used in chemistry laboratories and in the manufacturing of materials, which poses a serious risk to process safety, the natural environment, and human health. In this review, different tools for solvent-free organic reactions have been surveyed as an approach for green chemistry, where many of the solvents are known to upset our ecosystems so an enormous research effort has been exerted during the last decade to avoid the utilization of hazardous solvents and the number of publications on solvent-free reactions has increased nearly exponentially. Obviously, this reflects the great interest in solventless reactions. In our survey, we will highlight the solvent-free organic reaction as an approach for green chemistry to cover work published up to nearly 2022.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82154690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It was aimed to develop and validate the UV spectroscopic, the first-order derivative spectroscopy, and the HPLC method for determination of cefuroxime axetil in bulk and tablets and also in spiked human plasma samples by UV spectroscopy method. In the spectroscopic analyses, the maximum absorbance of cefuroxime axetil in acetonitrile was obtained at 277 nm wavelength in the spectra. In first-order derivative spectroscopy method, two peaks were observed in spectra, a maximum at 258 nm and a minimum at 298 nm. 298 nm wavelength was used in the study. In HPLC-UV study, parameters were chosen as follows: C18 column, 0.1% acetic acid-acetonitrile (30:70; v/v) for mobile phase, 1.0 mL/min of flow rate, 280 nm of wavelength, 10 μL of injection volume and etodolac (2.5 μg/mL) as internal standard. Accuracy, precision, recovery, linearity and sensitivity parameters were determined for each of the three methods. Developed and validated methods were successfully applied on 4 tablets which are named as Cefaks, Cefurol, Aksef ve Enfexia. As a result, it is claimed that proposed method is sensitive, precise, accurate, and successfully used in quality control studies in the drug industry.
{"title":"Determination of Cefuroxime Axetil in Tablet by HPLC, UV and First-Order Derivative Spectroscopy Methods & Plasma by UV Spectroscopy Method","authors":"A. Turan, Y. Kadioglu","doi":"10.18596/jotcsa.1222357","DOIUrl":"https://doi.org/10.18596/jotcsa.1222357","url":null,"abstract":"It was aimed to develop and validate the UV spectroscopic, the first-order derivative spectroscopy, and the HPLC method for determination of cefuroxime axetil in bulk and tablets and also in spiked human plasma samples by UV spectroscopy method. In the spectroscopic analyses, the maximum absorbance of cefuroxime axetil in acetonitrile was obtained at 277 nm wavelength in the spectra. In first-order derivative spectroscopy method, two peaks were observed in spectra, a maximum at 258 nm and a minimum at 298 nm. 298 nm wavelength was used in the study. In HPLC-UV study, parameters were chosen as follows: C18 column, 0.1% acetic acid-acetonitrile (30:70; v/v) for mobile phase, 1.0 mL/min of flow rate, 280 nm of wavelength, 10 μL of injection volume and etodolac (2.5 μg/mL) as internal standard. Accuracy, precision, recovery, linearity and sensitivity parameters were determined for each of the three methods. Developed and validated methods were successfully applied on 4 tablets which are named as Cefaks, Cefurol, Aksef ve Enfexia. As a result, it is claimed that proposed method is sensitive, precise, accurate, and successfully used in quality control studies in the drug industry.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83291823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Okeola, Taofeeqat Abu, A. Mohammed, M. Orosun, A. Baba, M. Adeboje
This study investigated the effects of prolonged storage conditions on the physicochemical parameter, toxic metals, microbial loads, and health risks assessment of randomly selected three brands of sachet and bottled water in North Central, Nigeria. One hundred eighty samples of water brands (sachet and bottled) were collected from 10 different factories and were grouped into three. They were analyzed immediately (initial), being exposed to mild sunlight (stored with a container) and exposed to intense sunlight (stored without a container) conditions for six weeks. The results of the physicochemical parameters (sachet and bottle) were within the limits set by the World Health Organization (WHO) and the Standard Organization of Nigeria (SON). While the results of heavy metals analysis for both sachet and bottled water recorded 0.15 - 0.51 mg/L (0.10 mg/L , 0.05 mg/L), 0.13 - 0.38 mg/L (0.015 mg/L, 0.01 mg/L) and 0.55 - 1.11 mg/L (0.03 mg/L, 0.3 mg/L) for Chromium (Cr), Lead (Pb) and Iron (Fe) respectively, as compared to the permissible limits (values in the bracket for each heavy metals) set by WHO and SON. The microbial analysis results ranged between 6.58 - 124.51 Cfu/100 mL, 0.52 - 37.56 Cfu/100 mL, 0.07 - 5.00 Cfu/100 mL, 0 - 2.07 Cfu/100 mL for Total Bacteria Count (TBC), Total Coliform Count (TCC), Faecal Coliform Count (FCC) and Total Fungal Count (TFC) respectively, which showed no effective quality control system. Incremental lifetime cancer risk (ILCR) assessment revealed a carcinogenic health risk to the populace drinking this water. The study concludes that water stored under sunlight for a long period is not good for human consumption and therefore adequate monitoring by the appropriate agencies is emphasized.
{"title":"Investigation on the Quality of Prolonged Storage of Packaged Water Commonly Produced in North Central, Nigeria","authors":"F. Okeola, Taofeeqat Abu, A. Mohammed, M. Orosun, A. Baba, M. Adeboje","doi":"10.18596/jotcsa.1116034","DOIUrl":"https://doi.org/10.18596/jotcsa.1116034","url":null,"abstract":"This study investigated the effects of prolonged storage conditions on the physicochemical parameter, toxic metals, microbial loads, and health risks assessment of randomly selected three brands of sachet and bottled water in North Central, Nigeria. One hundred eighty samples of water brands (sachet and bottled) were collected from 10 different factories and were grouped into three. They were analyzed immediately (initial), being exposed to mild sunlight (stored with a container) and exposed to intense sunlight (stored without a container) conditions for six weeks. The results of the physicochemical parameters (sachet and bottle) were within the limits set by the World Health Organization (WHO) and the Standard Organization of Nigeria (SON). While the results of heavy metals analysis for both sachet and bottled water recorded 0.15 - 0.51 mg/L (0.10 mg/L , 0.05 mg/L), 0.13 - 0.38 mg/L (0.015 mg/L, 0.01 mg/L) and 0.55 - 1.11 mg/L (0.03 mg/L, 0.3 mg/L) for Chromium (Cr), Lead (Pb) and Iron (Fe) respectively, as compared to the permissible limits (values in the bracket for each heavy metals) set by WHO and SON. The microbial analysis results ranged between 6.58 - 124.51 Cfu/100 mL, 0.52 - 37.56 Cfu/100 mL, 0.07 - 5.00 Cfu/100 mL, 0 - 2.07 Cfu/100 mL for Total Bacteria Count (TBC), Total Coliform Count (TCC), Faecal Coliform Count (FCC) and Total Fungal Count (TFC) respectively, which showed no effective quality control system. Incremental lifetime cancer risk (ILCR) assessment revealed a carcinogenic health risk to the populace drinking this water. The study concludes that water stored under sunlight for a long period is not good for human consumption and therefore adequate monitoring by the appropriate agencies is emphasized.","PeriodicalId":17299,"journal":{"name":"Journal of the Turkish Chemical Society Section A: Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88255680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：