Pub Date : 2019-01-28DOI: 10.26850/1678-4618EQJ.V44.1.2019.P40-52
R. L. Morais, L. F. Garcia, E. K. Moreno, Douglas Vieira Thomaz, L. Rodrigues, L. Brito, G. S. Lobón, G. Oliveira, M. F. Rodrigues, B. Vaz, E. Gil
The elimination of residual drugs from pharmaceutical and domestic sources is a growing concern, as they are able to reach water and soil resources and can present environmental and health risks even in very low concentrations. Traditional water and wastewater treatment systems have not been efficient in the removal of these compounds, evidencing the importance of the development of new remediation methods. In view of the applicability and versatility of electrocoagulation techniques in the removal of pollutants, the aim of this work is to evaluate the parameters: biochemical oxygen demand (BOD), chemical oxygen demand (COD), color, turbidity, algestone acetophenide (AAc) and estradiol enanthate (EEn) using a pilot treatment system, as well as phytotoxicity and Brine shrimp toxicity. The study showed good removal efficiency, comprising remarkable remediation performance assayed through BOD (61.5%), COD (58.6%), color (83.1%), turbidity (96.7%), AAc (77.0%) and EEn (56.7%) after 30 minutes. For toxicity, raw effluent was considered more phytotoxic for lettuce and cucumber seeds when compared to treated effluent. The results suggest that the pilot prototype was promising, providing an increase in both the germination potential and the root growth of the seeds (Lactuca sativa and Cucumis sativus) and a significant decrease in the acute toxicity to Artemia salina.
{"title":"Electrochemical remediation of industrial pharmaceutical wastewater containing hormones in a pilot scale treatment system","authors":"R. L. Morais, L. F. Garcia, E. K. Moreno, Douglas Vieira Thomaz, L. Rodrigues, L. Brito, G. S. Lobón, G. Oliveira, M. F. Rodrigues, B. Vaz, E. Gil","doi":"10.26850/1678-4618EQJ.V44.1.2019.P40-52","DOIUrl":"https://doi.org/10.26850/1678-4618EQJ.V44.1.2019.P40-52","url":null,"abstract":"The elimination of residual drugs from pharmaceutical and domestic sources is a growing concern, as they are able to reach water and soil resources and can present environmental and health risks even in very low concentrations. Traditional water and wastewater treatment systems have not been efficient in the removal of these compounds, evidencing the importance of the development of new remediation methods. In view of the applicability and versatility of electrocoagulation techniques in the removal of pollutants, the aim of this work is to evaluate the parameters: biochemical oxygen demand (BOD), chemical oxygen demand (COD), color, turbidity, algestone acetophenide (AAc) and estradiol enanthate (EEn) using a pilot treatment system, as well as phytotoxicity and Brine shrimp toxicity. The study showed good removal efficiency, comprising remarkable remediation performance assayed through BOD (61.5%), COD (58.6%), color (83.1%), turbidity (96.7%), AAc (77.0%) and EEn (56.7%) after 30 minutes. For toxicity, raw effluent was considered more phytotoxic for lettuce and cucumber seeds when compared to treated effluent. The results suggest that the pilot prototype was promising, providing an increase in both the germination potential and the root growth of the seeds (Lactuca sativa and Cucumis sativus) and a significant decrease in the acute toxicity to Artemia salina.","PeriodicalId":11506,"journal":{"name":"Eclética Química Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74583187","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}
Pub Date : 2018-12-05DOI: 10.26850/1678-4618EQJ.V43.4.2018.P25-36
M. A. Al.Maqtari, M. K. Al-qadasy, Y. Jamil, F. Al-Azab, A. A. Al-Gaadbi
The reaction of urea (ur) and glycine (gly) with the metal ions Co(ΙΙ), Ni(ΙΙ) and Cu(ΙΙ) in ethanolic solution of 1M:1L1:1L2 molar ratio (where M= Co(II), Ni(II) and Cu(II), and L1 = urea L2 = glycine) led to the preparation of complexes of the general formula [M(ur)(gly)(H2O)2]Cl. Elemental microanalysis (CHN), molar conductivity measurements, IR,1HNMR, Mass and UV-VIS spectroscopic, and magnetic susceptibility measurements were used for the characterization of the compounds. Thermal analyses were used for the complexes degradation characterization. The complexes have an octahedral geometry and are of electrolytic nature in DMSO solvent with the absence of inner-sphere coordination of the chloride anion. An inhibition zone was observed for Ni-urea-glycine complex against Escherichia coli when the biological activity was considered.
{"title":"Physicochemical and biological activity studies on complexes of some transition elements with mixed ligands of glycine and urea","authors":"M. A. Al.Maqtari, M. K. Al-qadasy, Y. Jamil, F. Al-Azab, A. A. Al-Gaadbi","doi":"10.26850/1678-4618EQJ.V43.4.2018.P25-36","DOIUrl":"https://doi.org/10.26850/1678-4618EQJ.V43.4.2018.P25-36","url":null,"abstract":"The reaction of urea (ur) and glycine (gly) with the metal ions Co(ΙΙ), Ni(ΙΙ) and Cu(ΙΙ) in ethanolic solution of 1M:1L1:1L2 molar ratio (where M= Co(II), Ni(II) and Cu(II), and L1 = urea L2 = glycine) led to the preparation of complexes of the general formula [M(ur)(gly)(H2O)2]Cl. Elemental microanalysis (CHN), molar conductivity measurements, IR,1HNMR, Mass and UV-VIS spectroscopic, and magnetic susceptibility measurements were used for the characterization of the compounds. Thermal analyses were used for the complexes degradation characterization. The complexes have an octahedral geometry and are of electrolytic nature in DMSO solvent with the absence of inner-sphere coordination of the chloride anion. An inhibition zone was observed for Ni-urea-glycine complex against Escherichia coli when the biological activity was considered.","PeriodicalId":11506,"journal":{"name":"Eclética Química Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81123098","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}
Pub Date : 2018-12-05DOI: 10.26850/1678-4618eqj.v43.4.2018.p37-43
E. H. Bindewald, João Carlos Rosa-Sobrinho, M. Bergamini, L. Marcolino-Junior
This work aims the development and optimization of an alternative method for ranitidine hydrochloride (RAN-HCl) determination. The proposed method was based on conductometric titration of RAN by precipitation of AgCl solid using a solution of AgNO3 as titrant. It was investigated the possibility of performing the titrations on hydroalcoholic and deionized water medium. A limit of detection of 1.0 mmol L-1 and 0.5 mmol L-1 were achieved for RAN titration in deionized water and in a 75:25 hydroalcoholic mixture, respectively. Such behavior is attributed to the dielectric constant of hydroalcoholic medium, which is lower than aqueous solution, making AgCl more insoluble and improving the resolution of the conductivity curve around the end point. Therefore, it is concluded that the conductometric titration method to determine RAN using AgNO3 as titrant proved to be feasible at low drug concentrations. The statistical calculations for obtained results suggested good precision for the conductometric method. According to t-test, there were no significant differences between found values at a 95% confidence level. Moreover, obtained results showed an excellent performance of the proposed method on quality control of RAN-HCl in generic formulations without any sample pretreatment.
{"title":"Simple, fast and inexpensive method for determination of ranitidine hydrochloride based on conductometric measurements","authors":"E. H. Bindewald, João Carlos Rosa-Sobrinho, M. Bergamini, L. Marcolino-Junior","doi":"10.26850/1678-4618eqj.v43.4.2018.p37-43","DOIUrl":"https://doi.org/10.26850/1678-4618eqj.v43.4.2018.p37-43","url":null,"abstract":"This work aims the development and optimization of an alternative method for ranitidine hydrochloride (RAN-HCl) determination. The proposed method was based on conductometric titration of RAN by precipitation of AgCl solid using a solution of AgNO3 as titrant. It was investigated the possibility of performing the titrations on hydroalcoholic and deionized water medium. A limit of detection of 1.0 mmol L-1 and 0.5 mmol L-1 were achieved for RAN titration in deionized water and in a 75:25 hydroalcoholic mixture, respectively. Such behavior is attributed to the dielectric constant of hydroalcoholic medium, which is lower than aqueous solution, making AgCl more insoluble and improving the resolution of the conductivity curve around the end point. Therefore, it is concluded that the conductometric titration method to determine RAN using AgNO3 as titrant proved to be feasible at low drug concentrations. The statistical calculations for obtained results suggested good precision for the conductometric method. According to t-test, there were no significant differences between found values at a 95% confidence level. Moreover, obtained results showed an excellent performance of the proposed method on quality control of RAN-HCl in generic formulations without any sample pretreatment.","PeriodicalId":11506,"journal":{"name":"Eclética Química Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75091358","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}
Pub Date : 2018-12-05DOI: 10.26850/1678-4618EQJ.V43.4.2018.P11-24
Y. Jamil, M. A. Al.Maqtari, F. Al-Azab, M. K. Al-qadasy, A. A. Al-Gaadbi
New Co(II), Ni(II) and Cu(II) complexes with urea and asparagine as ligands have been synthesized in (M:L1:L2) molar ratio (where M= Co(II), Ni(II) and Cu(II), L1 =urea, and L2 =asparagine) then identified by micro analytical data, molar conductance measurements, IR, 1HNMR, Mass, UV-VIS spectroscopies and magnetic susceptibility measurements. Thermal degradation studies were carried out by thermal analysis. These complexes have the general formula [M(L1)(L2)(H2O)n]Cl. The molar conductance values in DMSO solvent show the electrolytic nature of these complexes, indicating the outer-sphere coordination of the chloride anions with metal ions. The three complexes have an octahedral structure although urea has shown two modes of coordination. Thermal analysis study shows rapid decomposition reaction for Ni complex and the highest thermal stability for Cu complex. The kinetic parameters were determined from the thermal decomposition data using the Coats-Redfern method. Thermodynamic parameters were calculated using standard relations.
{"title":"Synthesis, Characterization and Comparative Thermal degradation study of Co(II), Ni(ΙΙ) and Cu(II) complexes with Asparagine and Urea as mixed ligands","authors":"Y. Jamil, M. A. Al.Maqtari, F. Al-Azab, M. K. Al-qadasy, A. A. Al-Gaadbi","doi":"10.26850/1678-4618EQJ.V43.4.2018.P11-24","DOIUrl":"https://doi.org/10.26850/1678-4618EQJ.V43.4.2018.P11-24","url":null,"abstract":"New Co(II), Ni(II) and Cu(II) complexes with urea and asparagine as ligands have been synthesized in (M:L1:L2) molar ratio (where M= Co(II), Ni(II) and Cu(II), L1 =urea, and L2 =asparagine) then identified by micro analytical data, molar conductance measurements, IR, 1HNMR, Mass, UV-VIS spectroscopies and magnetic susceptibility measurements. Thermal degradation studies were carried out by thermal analysis. These complexes have the general formula [M(L1)(L2)(H2O)n]Cl. The molar conductance values in DMSO solvent show the electrolytic nature of these complexes, indicating the outer-sphere coordination of the chloride anions with metal ions. The three complexes have an octahedral structure although urea has shown two modes of coordination. Thermal analysis study shows rapid decomposition reaction for Ni complex and the highest thermal stability for Cu complex. The kinetic parameters were determined from the thermal decomposition data using the Coats-Redfern method. Thermodynamic parameters were calculated using standard relations.","PeriodicalId":11506,"journal":{"name":"Eclética Química Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84237886","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}
Pub Date : 2018-12-05DOI: 10.26850/1678-4618EQJ.V43.4.2018.P44-49
H. C. Gutiérrez, M. C. Gutiérrez, G. I. F. Rivera, L. J. C. F. Rivera, D. F. R. Vallejo
We analyze the dynamics and the quantum thermodynamics of DNA in Symmetric-Peyrard-Bishop-Dauxois model (S-PBD) with solvent and external potentials and describe the transient conformational fluctuations using dark breather and the ground state wave function of the associate Schrodinger differential equation. We used the S-PBD, the Floquet theory, quantum thermodynamic and finite difference methods. We show that for lower coupling dark breather is present. We estimate the fluctuations or breathing of DNA. For the S-PBD model we have the stability of dark breather for k<0.004 and mobile breathers with coupling k=0.004. The fluctuations of the dark breather in the S-PBD model is approximately zero with the quantum thermodynamics. The viscous and external potential effect is direct proportional to hydrogen bond stretching.
{"title":"Dark breather using symmetric Morse, solvent and external potentials for DNA breathing","authors":"H. C. Gutiérrez, M. C. Gutiérrez, G. I. F. Rivera, L. J. C. F. Rivera, D. F. R. Vallejo","doi":"10.26850/1678-4618EQJ.V43.4.2018.P44-49","DOIUrl":"https://doi.org/10.26850/1678-4618EQJ.V43.4.2018.P44-49","url":null,"abstract":"We analyze the dynamics and the quantum thermodynamics of DNA in Symmetric-Peyrard-Bishop-Dauxois model (S-PBD) with solvent and external potentials and describe the transient conformational fluctuations using dark breather and the ground state wave function of the associate Schrodinger differential equation. We used the S-PBD, the Floquet theory, quantum thermodynamic and finite difference methods. We show that for lower coupling dark breather is present. We estimate the fluctuations or breathing of DNA. For the S-PBD model we have the stability of dark breather for k<0.004 and mobile breathers with coupling k=0.004. The fluctuations of the dark breather in the S-PBD model is approximately zero with the quantum thermodynamics. The viscous and external potential effect is direct proportional to hydrogen bond stretching.","PeriodicalId":11506,"journal":{"name":"Eclética Química Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81007241","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}
Pub Date : 2018-10-10DOI: 10.26850/1678-4618EQJ.V43.3.2018.P19-29
J. M. Franco, S. P. Pugine, A. M. Scatolini, M. Melo
The aim of the present study was to evaluate in vitro antioxidant capacity of Melissa extract (ME) (Melissa officinalis L.) and its protective effect on peroxyl radical-induced oxidative damage in erythrocytes. ME used in present study was obtained by rota-evaporation of the crude extract (ethanol:water/dried leaves). Total phenolic and flavonoids contend determination, 176.8 ± 13.2 mg GAE/g dw and 26.2 ± 3.2 mg QE/g dw, respectively). Total equivalent antioxidant activities, TEAC in mg TE/g dw, were 61.4 ± 5.5 and 512.4 ± 77.2 for respective FRAP assay and DPPH• radical-scavenging. The ME acts as an antioxidant on NO and O2•-, when ME exerted a higher antioxidant action on NO scavenging to compared to the ascorbic acid (1.9 times), however, the antioxidant capacity of ME on O2•- was lower than ascorbic acid (5.6 times). The values of hemolysis inhibition from ME (IC50, 2.0 ± 0.5 mg/mL) were higher than ascorbic acid (IC50, 7.1 ± 1.8 mg/mL). Extract of Melissa was able to eliminate biological free radicals, suggesting a potential to prevent oxidative damage in vivo. In fact, the ME exerted protective action on cell membrane lysis in situ.
{"title":"Antioxidant capacity of Melissa Officinalis L. on Biological Systems","authors":"J. M. Franco, S. P. Pugine, A. M. Scatolini, M. Melo","doi":"10.26850/1678-4618EQJ.V43.3.2018.P19-29","DOIUrl":"https://doi.org/10.26850/1678-4618EQJ.V43.3.2018.P19-29","url":null,"abstract":"The aim of the present study was to evaluate in vitro antioxidant capacity of Melissa extract (ME) (Melissa officinalis L.) and its protective effect on peroxyl radical-induced oxidative damage in erythrocytes. ME used in present study was obtained by rota-evaporation of the crude extract (ethanol:water/dried leaves). Total phenolic and flavonoids contend determination, 176.8 ± 13.2 mg GAE/g dw and 26.2 ± 3.2 mg QE/g dw, respectively). Total equivalent antioxidant activities, TEAC in mg TE/g dw, were 61.4 ± 5.5 and 512.4 ± 77.2 for respective FRAP assay and DPPH• radical-scavenging. The ME acts as an antioxidant on NO and O2•-, when ME exerted a higher antioxidant action on NO scavenging to compared to the ascorbic acid (1.9 times), however, the antioxidant capacity of ME on O2•- was lower than ascorbic acid (5.6 times). The values of hemolysis inhibition from ME (IC50, 2.0 ± 0.5 mg/mL) were higher than ascorbic acid (IC50, 7.1 ± 1.8 mg/mL). Extract of Melissa was able to eliminate biological free radicals, suggesting a potential to prevent oxidative damage in vivo. In fact, the ME exerted protective action on cell membrane lysis in situ.","PeriodicalId":11506,"journal":{"name":"Eclética Química Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82571378","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}
Pub Date : 2018-10-10DOI: 10.26850/1678-4618eqj.v43.3.2018.p10-18
Daniel Augusto Barra de Oliveira
Focal Adhesion Kinase (FAK) is a non-tyrosine kinase responsible to phosphorylate other enzymes associated with signal transduction. This biochemical process plays an important role to control cancer. FAK is found overexpressed in the organism during metastasis. Since FAK may be involved in the invasion and metastasis of cancer, novel molecules based on drug design have been synthesized over the past few years. The inhibitors are designed to mimic the natural substrate which is the ATP molecule. This work studied the hydrogen bonds performed between inhibitors and FAK and other electronic properties involved in this interaction. The molecular structure of FAK docked with the inhibitors was simulated using classical molecular dynamics. FAK/ inhibitor complex obtained by dynamic was optimized using quantum mechanical ab-initio calculation. Our results show that all inhibitors interact with Cys502 located in the FAK-binding site. Ab-initio calculations show that HOMO orbital is situated under Met499 and Glu500 amino acids indicating chemical reactivity in this region. The results of molecular dynamics combined with quantum chemical calculations show that the sulfonamide has a strong hydrogen bond with close distances, while the thiazole has a weak hydrogen bond with long distances. Sulfonamide has known good activity against FAK while the thiazole molecule has an unknown activity. These results allow predicting that the molecule of thiazole is a not good inhibitor to FAK inhibition.
{"title":"The correlation between electronic structure and antitumor activity of a seletive focal adhesion kinase inhibitors","authors":"Daniel Augusto Barra de Oliveira","doi":"10.26850/1678-4618eqj.v43.3.2018.p10-18","DOIUrl":"https://doi.org/10.26850/1678-4618eqj.v43.3.2018.p10-18","url":null,"abstract":"Focal Adhesion Kinase (FAK) is a non-tyrosine kinase responsible to phosphorylate other enzymes associated with signal transduction. This biochemical process plays an important role to control cancer. FAK is found overexpressed in the organism during metastasis. Since FAK may be involved in the invasion and metastasis of cancer, novel molecules based on drug design have been synthesized over the past few years. The inhibitors are designed to mimic the natural substrate which is the ATP molecule. This work studied the hydrogen bonds performed between inhibitors and FAK and other electronic properties involved in this interaction. The molecular structure of FAK docked with the inhibitors was simulated using classical molecular dynamics. FAK/ inhibitor complex obtained by dynamic was optimized using quantum mechanical ab-initio calculation. Our results show that all inhibitors interact with Cys502 located in the FAK-binding site. Ab-initio calculations show that HOMO orbital is situated under Met499 and Glu500 amino acids indicating chemical reactivity in this region. The results of molecular dynamics combined with quantum chemical calculations show that the sulfonamide has a strong hydrogen bond with close distances, while the thiazole has a weak hydrogen bond with long distances. Sulfonamide has known good activity against FAK while the thiazole molecule has an unknown activity. These results allow predicting that the molecule of thiazole is a not good inhibitor to FAK inhibition.","PeriodicalId":11506,"journal":{"name":"Eclética Química Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74195602","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}
Pub Date : 2018-10-10DOI: 10.26850/1678-4618EQJ.V43.3.2018.P45-58
I. L. C. Junior, L. Finger, Poliana Quitaiski, Samuel Mathias Neitzke, Josue Victor Besen, Maike Krug Correa, J. Mees
In this study, the biosorption was used on the removal of 5G blue dye using rice husk residue. Was evaluated the influence of temperature and pH on the biomass pretreated with H3PO4 and NH4Cl. The tests were realized in batch with previous determination of point of zero charge (PZC). Analytical measurements were performed by UV-Vis spectroscopy. It was observed a major influence of pH and temperature on the biosorption capacity of the dye, being the highest removal obtained for the condition of pH 2 and temperature of 50 °C. The time for the biomass-dye system to reach equilibrium was around 45 min. The kinetic model of pseudo-first order adequately represented experimental data and had a good correlation coefficient. In the equilibrium study, it was verified that the Langmuir isotherm was the best fit for the experimental data, with a maximum biosorption capacity of 3,84 mg g-1. The use of rice husk as a biosorbent for the removal of reactive blue 5G dye can be considered promising for the abundance of this residue and the observed sorption capacity
{"title":"Biosorption of 5G blue reactive dye using waste rice husk","authors":"I. L. C. Junior, L. Finger, Poliana Quitaiski, Samuel Mathias Neitzke, Josue Victor Besen, Maike Krug Correa, J. Mees","doi":"10.26850/1678-4618EQJ.V43.3.2018.P45-58","DOIUrl":"https://doi.org/10.26850/1678-4618EQJ.V43.3.2018.P45-58","url":null,"abstract":"In this study, the biosorption was used on the removal of 5G blue dye using rice husk residue. Was evaluated the influence of temperature and pH on the biomass pretreated with H3PO4 and NH4Cl. The tests were realized in batch with previous determination of point of zero charge (PZC). Analytical measurements were performed by UV-Vis spectroscopy. It was observed a major influence of pH and temperature on the biosorption capacity of the dye, being the highest removal obtained for the condition of pH 2 and temperature of 50 °C. The time for the biomass-dye system to reach equilibrium was around 45 min. The kinetic model of pseudo-first order adequately represented experimental data and had a good correlation coefficient. In the equilibrium study, it was verified that the Langmuir isotherm was the best fit for the experimental data, with a maximum biosorption capacity of 3,84 mg g-1. The use of rice husk as a biosorbent for the removal of reactive blue 5G dye can be considered promising for the abundance of this residue and the observed sorption capacity","PeriodicalId":11506,"journal":{"name":"Eclética Química Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81958145","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}
Pub Date : 2018-10-10DOI: 10.26850/1678-4618EQJ.V43.3.2018.P30-36
T. C. Filippe, Franciane de Almeida Brehm Goulart, Alinne Mizukawa, J. Azevedo
The presence of personal care products in the environment is recent and relatively few researches work with the quantification of this class of emerging contaminants in Brazil. However, a wide variety of these products is continuously released into the aquatic environment. The growing interest in these substances occurs mainly because they exhibit biological activity in very low concentrations, which gives great environmental relevance. The difficulty of detecting and quantifying such contaminants in the environment encourages the development and validation of appropriate analytical methods for this purpose. Therefore, the present study aims to validate a methodology and verify its efficiency in the determination of six personal care products, among them parabens and triclosan. The samples were submitted to the solid phase extraction process and were later analyzed by gas chromatography coupled with mass spectrometry for the determination of personal care products. The validation of the methodology used was based on the standards established by the National Health Surveillance Agency. The extraction and quantification method were efficient for the determination of these analytes in water samples.
{"title":"Validation of analytical methodology for determination of Personal Care Products in environmental matrix by GC-MSMS","authors":"T. C. Filippe, Franciane de Almeida Brehm Goulart, Alinne Mizukawa, J. Azevedo","doi":"10.26850/1678-4618EQJ.V43.3.2018.P30-36","DOIUrl":"https://doi.org/10.26850/1678-4618EQJ.V43.3.2018.P30-36","url":null,"abstract":"The presence of personal care products in the environment is recent and relatively few researches work with the quantification of this class of emerging contaminants in Brazil. However, a wide variety of these products is continuously released into the aquatic environment. The growing interest in these substances occurs mainly because they exhibit biological activity in very low concentrations, which gives great environmental relevance. The difficulty of detecting and quantifying such contaminants in the environment encourages the development and validation of appropriate analytical methods for this purpose. Therefore, the present study aims to validate a methodology and verify its efficiency in the determination of six personal care products, among them parabens and triclosan. The samples were submitted to the solid phase extraction process and were later analyzed by gas chromatography coupled with mass spectrometry for the determination of personal care products. The validation of the methodology used was based on the standards established by the National Health Surveillance Agency. The extraction and quantification method were efficient for the determination of these analytes in water samples.","PeriodicalId":11506,"journal":{"name":"Eclética Química Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75895429","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}
Pub Date : 2018-10-10DOI: 10.26850/1678-4618EQJ.V43.3.2018.P37-44
R. C. Borges, L. M. Marques, C. Mahler, A. V. B. Bernedo
Phosphate fertilizer industry produces phosphoric acid from phosphate rocks, and as a byproduct, it produces phosphogypsum, also known as agricultural gypsum. This material was stock an open-air stacks near the producing units. In order to determine levels of rare-earth elements in phosphogypsum stacks, located in Imbituba, Brazil. Samples of 1000 grams of phosphogypsum were collected in nine different points in stack 1. The concentration of rare-earth elements was determined through neutron activation analysis and results indicate significant values of rare earth elements in the phosphogypsum from Imbituba, when compared to the values of the Earth’s crust.
{"title":"Determination of the concentration of Ce, La, Sm and Eu in a phosphogypsum stack, in Imbituba city, Santa Catarina, Brazil","authors":"R. C. Borges, L. M. Marques, C. Mahler, A. V. B. Bernedo","doi":"10.26850/1678-4618EQJ.V43.3.2018.P37-44","DOIUrl":"https://doi.org/10.26850/1678-4618EQJ.V43.3.2018.P37-44","url":null,"abstract":"Phosphate fertilizer industry produces phosphoric acid from phosphate rocks, and as a byproduct, it produces phosphogypsum, also known as agricultural gypsum. This material was stock an open-air stacks near the producing units. In order to determine levels of rare-earth elements in phosphogypsum stacks, located in Imbituba, Brazil. Samples of 1000 grams of phosphogypsum were collected in nine different points in stack 1. The concentration of rare-earth elements was determined through neutron activation analysis and results indicate significant values of rare earth elements in the phosphogypsum from Imbituba, when compared to the values of the Earth’s crust.","PeriodicalId":11506,"journal":{"name":"Eclética Química Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90327830","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}
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