Pub Date : 2023-10-06DOI: 10.21577/0103-5053.20230059
Ruth Paulino, R. Alves, Joanna Matalińska, Piotr F. J. Lipiński, R. Freitas
The search for compounds with affinity for both mu-opioid receptor (MOR) and sigma-1 receptor (σ1R) is one of the innovative directions to develop painkillers with reduced side effects. Additionally, triazole scaffolds have been extensively explored in the last two decades in medicinal chemistry. In this context, we synthesized a series of new triazole fentanyl derivatives and evaluated their affinity for both MOR and σ1R. The binding affinity of the compounds for human MOR was determined in competitive radioligand binding assays, using fentanyl as standard. For the assays with σ1R, a σ1R agonist (SKF10047) was employed. The most active analogue was 6d which moderately binds to MOR with half-maximal inhibitory concentrations (IC50) = 1.9 μM and to σ1R with IC50 = 6.9 μM. Molecular docking calculations were carried out, providing a structural elucidation for the observed values of affinity. Absorption, distribution, metabolism, and excretion toxicity (ADMET) parameters for the new compounds were simulated with the SwissADME tool
{"title":"Synthesis of Fentanyl Triazole Derivatives and their Affinity for Mu-Opioid and Sigma-1 Receptors","authors":"Ruth Paulino, R. Alves, Joanna Matalińska, Piotr F. J. Lipiński, R. Freitas","doi":"10.21577/0103-5053.20230059","DOIUrl":"https://doi.org/10.21577/0103-5053.20230059","url":null,"abstract":"The search for compounds with affinity for both mu-opioid receptor (MOR) and sigma-1 receptor (σ1R) is one of the innovative directions to develop painkillers with reduced side effects. Additionally, triazole scaffolds have been extensively explored in the last two decades in medicinal chemistry. In this context, we synthesized a series of new triazole fentanyl derivatives and evaluated their affinity for both MOR and σ1R. The binding affinity of the compounds for human MOR was determined in competitive radioligand binding assays, using fentanyl as standard. For the assays with σ1R, a σ1R agonist (SKF10047) was employed. The most active analogue was 6d which moderately binds to MOR with half-maximal inhibitory concentrations (IC50) = 1.9 μM and to σ1R with IC50 = 6.9 μM. Molecular docking calculations were carried out, providing a structural elucidation for the observed values of affinity. Absorption, distribution, metabolism, and excretion toxicity (ADMET) parameters for the new compounds were simulated with the SwissADME tool","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68337967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.21577/0103-5053.20230064
N. A. Villacrés, É. Cavalheiro, Carla C Schmitt, T. Venâncio, H. Alarcón, A. Valderrama
Composite films are an alternative in the replacement of synthetic polymers. These films can be prepared from polysaccharides and used to store various drugs to be applied in different areas. In addition, aminoethoxyvinylglycine (AVG) is an ethylene inhibitor that prolongs shelf life of food. For this reason, this research aimed to take advantage of the brown algae Macrocystis pyrifera and Lessonia trabeculata to extract sodium alginate and produce films composed of sodium alginate/ kappa-carrageenan/iota-carrageenan, which were plasticized with glycerol and polyethylene glycol 400 and loaded with aminoethoxyvinylglycine. The extracted sodium alginate was characterized by 1 H and 13C nuclear magnetic resonance (NMR), size exclusion chromatography coupled with multi-angle light scattering (SEC-MALS), thermogravimetry (TG/DTG), Fourier transform infrared (FTIR), and X-ray diffraction (XRD); and the composite films were characterized by FTIR, XRD, TG/DTG, and scanning electron microscopy (SEM). Then, the drug release kinetics were investigated using Higuchi and Korsmeyer-Peppas kinetic models. The extracted alginates obtained were of low molecular weight, and the films showed desirable properties for AVG release. Furthermore, drug release profiles revealed that AVG release is governed by Fick’s Law, and this is favored at low temperatures. In summary, sodium alginate allows the preparation of composite films, which can replace synthetic polymers to be used in the loading and releasing of drugs.
{"title":"Preparation of Composite Films of Sodium Alginate-Based Extracted from Seaweeds Macrocystis pyrifera and Lessonia trabeculata Loaded with Aminoethoxyvinylglycine","authors":"N. A. Villacrés, É. Cavalheiro, Carla C Schmitt, T. Venâncio, H. Alarcón, A. Valderrama","doi":"10.21577/0103-5053.20230064","DOIUrl":"https://doi.org/10.21577/0103-5053.20230064","url":null,"abstract":"Composite films are an alternative in the replacement of synthetic polymers. These films can be prepared from polysaccharides and used to store various drugs to be applied in different areas. In addition, aminoethoxyvinylglycine (AVG) is an ethylene inhibitor that prolongs shelf life of food. For this reason, this research aimed to take advantage of the brown algae Macrocystis pyrifera and Lessonia trabeculata to extract sodium alginate and produce films composed of sodium alginate/ kappa-carrageenan/iota-carrageenan, which were plasticized with glycerol and polyethylene glycol 400 and loaded with aminoethoxyvinylglycine. The extracted sodium alginate was characterized by 1 H and 13C nuclear magnetic resonance (NMR), size exclusion chromatography coupled with multi-angle light scattering (SEC-MALS), thermogravimetry (TG/DTG), Fourier transform infrared (FTIR), and X-ray diffraction (XRD); and the composite films were characterized by FTIR, XRD, TG/DTG, and scanning electron microscopy (SEM). Then, the drug release kinetics were investigated using Higuchi and Korsmeyer-Peppas kinetic models. The extracted alginates obtained were of low molecular weight, and the films showed desirable properties for AVG release. Furthermore, drug release profiles revealed that AVG release is governed by Fick’s Law, and this is favored at low temperatures. In summary, sodium alginate allows the preparation of composite films, which can replace synthetic polymers to be used in the loading and releasing of drugs.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68339125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.21577/0103-5053.20230052
E. D. Barros, Evaldo dos Santos Monção Filho, Mariluce Fonseca, P. Alves, A. L. Santos, C. Feitosa, Dulce Helena Silva, Pedro M S Costa, C. Pessoa, Carmem D L Campos, C. Monteiro, M. Chaves, G. V. Vieira Júnior
Toads of the Rhinella genus have a pair of paratoid glands that store biological secretions of high toxicity and varied chemical composition, rich in biologically active compounds. The present work aimed to carry out the investigation of the metabolomic profile and evaluation of the biological potential of the secretion paratoid glands (PGS) from Rhinella granulosa. The paratoid secretion was collected in the Piauí state (Brazil), extracted with methanol and the extract was analyzed by ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry. Fifty chemical constituents were identified. The extract showed cytotoxicity against tumor cell lines of the central nervous system (half maximal inhibitory concentration (IC50) = 1.9 µg mL-1) and prostate (IC50 = 1.6 µg mL-1), unsatisfactory antimicrobial potential (minimal inhibitory concentration (MIC) > 312 µg mL-1) and inhibited the enzyme acetylcholinesterase (IC50 = 5.119 mg mL-1). The results presented relevant information about the PGS and contributed to the understanding of the metabolomic and biological potential of R. granulosa.
{"title":"Unraveling the Metabolomic Profile and Bioactivities of the Paratoid Gland Secretion from Rhinella granulosa","authors":"E. D. Barros, Evaldo dos Santos Monção Filho, Mariluce Fonseca, P. Alves, A. L. Santos, C. Feitosa, Dulce Helena Silva, Pedro M S Costa, C. Pessoa, Carmem D L Campos, C. Monteiro, M. Chaves, G. V. Vieira Júnior","doi":"10.21577/0103-5053.20230052","DOIUrl":"https://doi.org/10.21577/0103-5053.20230052","url":null,"abstract":"Toads of the Rhinella genus have a pair of paratoid glands that store biological secretions of high toxicity and varied chemical composition, rich in biologically active compounds. The present work aimed to carry out the investigation of the metabolomic profile and evaluation of the biological potential of the secretion paratoid glands (PGS) from Rhinella granulosa. The paratoid secretion was collected in the Piauí state (Brazil), extracted with methanol and the extract was analyzed by ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry. Fifty chemical constituents were identified. The extract showed cytotoxicity against tumor cell lines of the central nervous system (half maximal inhibitory concentration (IC50) = 1.9 µg mL-1) and prostate (IC50 = 1.6 µg mL-1), unsatisfactory antimicrobial potential (minimal inhibitory concentration (MIC) > 312 µg mL-1) and inhibited the enzyme acetylcholinesterase (IC50 = 5.119 mg mL-1). The results presented relevant information about the PGS and contributed to the understanding of the metabolomic and biological potential of R. granulosa.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68335116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.21577/0103-5053.20230058
A. Amaral, Julia Willig, C. Olguin, I. Oliveira, H. Stefani, G. Botteselle, F. Manarin
A novel class of potential herbicides, 3-indolylglycines were synthesized using an effective, green and rapid approach via multicomponent reaction (aza-Friedel-Crafts) between indoles, aldehydes and anilines in a water/sodium dodecyl sulfate system. The main advantages of this methodology are ease of handling, scalable to gram scale and a metal-free approach. The reaction is compatible with a variety of functional groups, obtaining the desired products in moderate to excellent yields. The biological activity of the 3-indolylglycines was evaluated, and it was found that these compounds interfere with the germination and radicle growth of Lactuca sativa, mainly the compound 4k.
{"title":"Synthesis and Phytotoxic Evaluation of 3-Indolylglycine Derivatives as New Natural-Like Herbicides","authors":"A. Amaral, Julia Willig, C. Olguin, I. Oliveira, H. Stefani, G. Botteselle, F. Manarin","doi":"10.21577/0103-5053.20230058","DOIUrl":"https://doi.org/10.21577/0103-5053.20230058","url":null,"abstract":"A novel class of potential herbicides, 3-indolylglycines were synthesized using an effective, green and rapid approach via multicomponent reaction (aza-Friedel-Crafts) between indoles, aldehydes and anilines in a water/sodium dodecyl sulfate system. The main advantages of this methodology are ease of handling, scalable to gram scale and a metal-free approach. The reaction is compatible with a variety of functional groups, obtaining the desired products in moderate to excellent yields. The biological activity of the 3-indolylglycines was evaluated, and it was found that these compounds interfere with the germination and radicle growth of Lactuca sativa, mainly the compound 4k.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68336980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.21577/0103-5053.20230054
Wenkang Ren, Jiale Wu, Jiafeng Wang, Haijun Wang, Ying Han, Yu Lin, M. Bu
Ergosterol peroxide (EP) has been extensively studied for its antitumor activities. However, its further development has been restricted due to its limited intracellular accumulation and poor aqueous solubility. In this study, a novel triphenylphosphonium cation (TPP+) moiety was coupled to ergosterol peroxide to precisely target it at tumor cell mitochondria. The synthesized Mito-EP derivatives Mito-EP-3a-3d displayed stronger cytotoxicity than the EP parent and exhibited selectively cytotoxic effects between cancer cells and normal gastric epithelial (GES-1) cells. The most potent compound, Mito-EP-3b, was 9.7-fold more efficacious than ergosterol peroxide in the MCF-7 (breast cancer) cell line and showed good selectivity (SI = IC50GES-1/IC50MCF-7 = 4.04, IC50: concentrations to inhibit 50% of cell growth). Furthermore, Mito-EP-3b was able to decrease the mitochondrial membrane potential and induced reactive oxygen species production, accompanied by activating the expression of cytochrome c and Bax, while Bcl-2 expression was suppressed. The molecular mechanism may refer to the mitochondrial apoptotic pathway. Overall, the above results incentivize the further study of Mito-EP-3b derivatives as potent anticancer agents.
{"title":"Mitochondria-Targeted Ergosterol Peroxide Derivatives: Synthesis, Anticancer Properties and Their Preliminary Mechanism of Inhibiting MCF-7 Cell Proliferation","authors":"Wenkang Ren, Jiale Wu, Jiafeng Wang, Haijun Wang, Ying Han, Yu Lin, M. Bu","doi":"10.21577/0103-5053.20230054","DOIUrl":"https://doi.org/10.21577/0103-5053.20230054","url":null,"abstract":"Ergosterol peroxide (EP) has been extensively studied for its antitumor activities. However, its further development has been restricted due to its limited intracellular accumulation and poor aqueous solubility. In this study, a novel triphenylphosphonium cation (TPP+) moiety was coupled to ergosterol peroxide to precisely target it at tumor cell mitochondria. The synthesized Mito-EP derivatives Mito-EP-3a-3d displayed stronger cytotoxicity than the EP parent and exhibited selectively cytotoxic effects between cancer cells and normal gastric epithelial (GES-1) cells. The most potent compound, Mito-EP-3b, was 9.7-fold more efficacious than ergosterol peroxide in the MCF-7 (breast cancer) cell line and showed good selectivity (SI = IC50GES-1/IC50MCF-7 = 4.04, IC50: concentrations to inhibit 50% of cell growth). Furthermore, Mito-EP-3b was able to decrease the mitochondrial membrane potential and induced reactive oxygen species production, accompanied by activating the expression of cytochrome c and Bax, while Bcl-2 expression was suppressed. The molecular mechanism may refer to the mitochondrial apoptotic pathway. Overall, the above results incentivize the further study of Mito-EP-3b derivatives as potent anticancer agents.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68336374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.21577/0103-5053.20230050
Fernando Olivares, Francisco Lazcano, M. Castillo, M. Barua, J. Escalada, Graciela Pinto Vitorino
This research aims to study fluconazole (FNZ)-solvent interactions in pure solvents through theoretical and experimental solvatochromism. This study showed a bathochromic shift as the polarity of the solvent increases, where the excited state of FNZ is of higher polarity and lower energy than that of the ground state. The multiparametric statistical analysis highlighted solvent polarizability, dispersion, and electronic induction as solvent parameters of great importance, with the basicity of solvent and hydrogen bond acceptor capacity as having certain relevance. The thermochromic effect was also determined by exposing the three pKa values of FNZ. In conclusion, this study shows the importance of the π-π stacking interaction of the FNZ dihalogenated phenyl ring, the solvent basicity for the hydroxyl group, and its acidity for the N4’ of one of the triazoles stand out, as well as the acid-base equilibria involving the -OH group and the two N4’.
{"title":"Solvatochromism and Thermochromism of Fluconazole: An Experimental and Theoretical Study","authors":"Fernando Olivares, Francisco Lazcano, M. Castillo, M. Barua, J. Escalada, Graciela Pinto Vitorino","doi":"10.21577/0103-5053.20230050","DOIUrl":"https://doi.org/10.21577/0103-5053.20230050","url":null,"abstract":"This research aims to study fluconazole (FNZ)-solvent interactions in pure solvents through theoretical and experimental solvatochromism. This study showed a bathochromic shift as the polarity of the solvent increases, where the excited state of FNZ is of higher polarity and lower energy than that of the ground state. The multiparametric statistical analysis highlighted solvent polarizability, dispersion, and electronic induction as solvent parameters of great importance, with the basicity of solvent and hydrogen bond acceptor capacity as having certain relevance. The thermochromic effect was also determined by exposing the three pKa values of FNZ. In conclusion, this study shows the importance of the π-π stacking interaction of the FNZ dihalogenated phenyl ring, the solvent basicity for the hydroxyl group, and its acidity for the N4’ of one of the triazoles stand out, as well as the acid-base equilibria involving the -OH group and the two N4’.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68334029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.21577/0103-5053.20230055
Veronica Santos, T. Felix, I. Mantovani, Rodrigo Balen, José da Cunha Neto, C. Fernandes, N. Debacher
Petroleum reserves available worldwide are geologically based mainly on sedimentary and carbonate rocks, and the reservoir performance depends on the intrinsic properties of each rock and their response to changes in wettability. Recently, the change in wettability with low-salinity brine has been used to improve the oil recovery, which is an environmentally friendly and low investment, but there is no unanimity about the mechanisms of oil recovery process. Therefore, the aim of this study is to investigate the process involved in the wettability associated with interactions between the surface of powdered reservoir rock samples and the surrounding fluids. The reservoir rock surface (sandstone, calcite and dolomite) was evaluated under three different conditions. The total amount of adsorbed oil on aged samples was twice as high in carbonate rocks as in sandstone. The thermal gravimetric analysis (TGA) for the desorption steps of the organic fraction on dolomite and calcite indicates that the treatment under high brine concentration favored the oil desorption and the opposite result was observed for sandstone. This behavior suggests that carbonate rocks adsorb more strongly the organic phase compared to sandstone.
{"title":"Evaluation of Wettability Alteration by Oil Doped with Organic Acid and Low-High Brine Solutions in Sandstone and Carbonate Rocks","authors":"Veronica Santos, T. Felix, I. Mantovani, Rodrigo Balen, José da Cunha Neto, C. Fernandes, N. Debacher","doi":"10.21577/0103-5053.20230055","DOIUrl":"https://doi.org/10.21577/0103-5053.20230055","url":null,"abstract":"Petroleum reserves available worldwide are geologically based mainly on sedimentary and carbonate rocks, and the reservoir performance depends on the intrinsic properties of each rock and their response to changes in wettability. Recently, the change in wettability with low-salinity brine has been used to improve the oil recovery, which is an environmentally friendly and low investment, but there is no unanimity about the mechanisms of oil recovery process. Therefore, the aim of this study is to investigate the process involved in the wettability associated with interactions between the surface of powdered reservoir rock samples and the surrounding fluids. The reservoir rock surface (sandstone, calcite and dolomite) was evaluated under three different conditions. The total amount of adsorbed oil on aged samples was twice as high in carbonate rocks as in sandstone. The thermal gravimetric analysis (TGA) for the desorption steps of the organic fraction on dolomite and calcite indicates that the treatment under high brine concentration favored the oil desorption and the opposite result was observed for sandstone. This behavior suggests that carbonate rocks adsorb more strongly the organic phase compared to sandstone.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68336587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.21577/0103-5053.20230066
F. Xavier, A. Silva, M. Lima, M. D. da Fonseca, M. da Conceição
Annual world production of sisal is estimated to be 400,000 tons, but the processing of sisal fiber generates around 160,000 tons of waste per year. The sisal bagasse is discarded, even though it is about 60% carbohydrates in its structure. Therefore, this work seeks to add value to sisal bagasse through the production of cellulose acetate membranes aimed at removing inhibitors from the fermentation process. The membrane was developed using a cellulose acetate polymer synthesized from cellulose isolated from sisal bagasse. Alkaline and acid pre-treatments resulted in 90% pure cellulose. The obtained cellulose acetate was confirmed by infrared spectroscopy. In the synthesis of the membranes, the influence of agitation time and temperature of the bath on the selectivity and porosity were evaluated in four tests, the third condition stood out with porosity of 26.23% and selectivity of 94.51% in the removal of the furfural and 36.62% of the acetic acid.
{"title":"Potential Application of Membrane Obtained from Sisal Bagasse in the Removal of Inhibitors from the Fermentation Process","authors":"F. Xavier, A. Silva, M. Lima, M. D. da Fonseca, M. da Conceição","doi":"10.21577/0103-5053.20230066","DOIUrl":"https://doi.org/10.21577/0103-5053.20230066","url":null,"abstract":"Annual world production of sisal is estimated to be 400,000 tons, but the processing of sisal fiber generates around 160,000 tons of waste per year. The sisal bagasse is discarded, even though it is about 60% carbohydrates in its structure. Therefore, this work seeks to add value to sisal bagasse through the production of cellulose acetate membranes aimed at removing inhibitors from the fermentation process. The membrane was developed using a cellulose acetate polymer synthesized from cellulose isolated from sisal bagasse. Alkaline and acid pre-treatments resulted in 90% pure cellulose. The obtained cellulose acetate was confirmed by infrared spectroscopy. In the synthesis of the membranes, the influence of agitation time and temperature of the bath on the selectivity and porosity were evaluated in four tests, the third condition stood out with porosity of 26.23% and selectivity of 94.51% in the removal of the furfural and 36.62% of the acetic acid.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68338658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.21577/0103-5053.20230053
Jeovana Pacheco, Jhonathas Brito, C. D. dos Santos, C. Bezerra, F. Damos, R. Luz
Chloroquine is a drug belonging to the aminoquinoline family that is widely used for treating diseases such as lupus, cancer, and malaria. In this sense, the present work describes the development of a simple method based on electrogenerated chemiluminescence (ECL) and a screen-printed carbon electrode (SPE) modified with carbon black for chloroquine determination. The carbon black modified SPE was characterized by scanning electron microscopy, Raman spectroscopy, cyclic voltammetry and linear sweep voltammetry to obtain the ECL-potential curves. The ECL method is based on the chemiluminescence resulting from the interaction between chloroquine and the tris(2’2-bipyridyl) ruthenium(II) complex. Under optimized experimental conditions, the method showed a wide linear working range between 0.5 and 500 µmol L-1. The method presented good precision and accuracy in drug samples used in the treatment of malaria and artificial urine sample, showing recovery values from 100 to 103% and 99 to 103%, respectively.
{"title":"A Simple Method for Determination of Chloroquine Based on Electrogenerated Chemiluminescence","authors":"Jeovana Pacheco, Jhonathas Brito, C. D. dos Santos, C. Bezerra, F. Damos, R. Luz","doi":"10.21577/0103-5053.20230053","DOIUrl":"https://doi.org/10.21577/0103-5053.20230053","url":null,"abstract":"Chloroquine is a drug belonging to the aminoquinoline family that is widely used for treating diseases such as lupus, cancer, and malaria. In this sense, the present work describes the development of a simple method based on electrogenerated chemiluminescence (ECL) and a screen-printed carbon electrode (SPE) modified with carbon black for chloroquine determination. The carbon black modified SPE was characterized by scanning electron microscopy, Raman spectroscopy, cyclic voltammetry and linear sweep voltammetry to obtain the ECL-potential curves. The ECL method is based on the chemiluminescence resulting from the interaction between chloroquine and the tris(2’2-bipyridyl) ruthenium(II) complex. Under optimized experimental conditions, the method showed a wide linear working range between 0.5 and 500 µmol L-1. The method presented good precision and accuracy in drug samples used in the treatment of malaria and artificial urine sample, showing recovery values from 100 to 103% and 99 to 103%, respectively.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68335702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.21577/0103-5053.20230061
M. Porcel, Júnior Staudt, Gustavo Spohr, Camila da Silva, C. Borba
The objective of this paper was to evaluate the kinetics of the hydrolysis of soybean oil by the action of the Lipozyme® TL IM enzyme varying the operational conditions of molar ratio water/oil (9:1-60:1) and temperature (40-64 °C). To describe the experimental data, a mathematical model based on the kinetic mechanism of Ping-Pong Bi Bi (PPBB) was proposed, in which the following steps were not considered formation of the complex enzyme/oil substrate, and formation of the acylated enzyme/oil substrate complex. The results of enzymatic hydrolysis of soybean oil indicated a yield in free fatty acids of 76% at the molar ratio of 46:1 and temperature of 52 °C. Furthermore, based on the values of the determination coefficient and root mean square error, the mathematical model based on the kinetic mechanism of PPBB showed good agreement with the experimental data in a relatively wide temperature range. Thus, it can be a useful tool for the optimization and assessment of the mechanisms of enzymatic hydrolysis of vegetable oil.
{"title":"Effect of the Temperature and Molar Ratio of Water-Oil on the Enzymatic Hydrolysis Kinetics of the Soybean Oil: Experimental and Mathematical Modeling","authors":"M. Porcel, Júnior Staudt, Gustavo Spohr, Camila da Silva, C. Borba","doi":"10.21577/0103-5053.20230061","DOIUrl":"https://doi.org/10.21577/0103-5053.20230061","url":null,"abstract":"The objective of this paper was to evaluate the kinetics of the hydrolysis of soybean oil by the action of the Lipozyme® TL IM enzyme varying the operational conditions of molar ratio water/oil (9:1-60:1) and temperature (40-64 °C). To describe the experimental data, a mathematical model based on the kinetic mechanism of Ping-Pong Bi Bi (PPBB) was proposed, in which the following steps were not considered formation of the complex enzyme/oil substrate, and formation of the acylated enzyme/oil substrate complex. The results of enzymatic hydrolysis of soybean oil indicated a yield in free fatty acids of 76% at the molar ratio of 46:1 and temperature of 52 °C. Furthermore, based on the values of the determination coefficient and root mean square error, the mathematical model based on the kinetic mechanism of PPBB showed good agreement with the experimental data in a relatively wide temperature range. Thus, it can be a useful tool for the optimization and assessment of the mechanisms of enzymatic hydrolysis of vegetable oil.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68338843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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