Pub Date : 2023-10-23DOI: 10.21577/0103-5053.20230126
B. Goulart, B. Vizioli, Evaldo Luiz Espindola, C. Montagner
The main objective of this work was to develop and validate an analytical method using solid-liquid extraction and liquid chromatography coupled with mass spectrometry in tandem (LC-MS/MS) for the simultaneous determination of the herbicide 2-(2,4-dichlorophenoxy)acetic acid (2,4-D) and the insecticide fipronil and its degradation products, fipronil sulfone and fipronil sulfide in different types of soil from Brazil (Oxisol and Entisol). Solid-liquid extraction was performed in two cycles using 20 mL of dichloromethane per cycle and sonication. The extraction efficiency of 2,4-D was more influenced by soil composition than the other compounds. The limits of quantification of the method were between 0.015 and 0.75 mg kg-1 and recovery values from 61 to 118%, with a maximum relative standard deviation (RSD) value of 4%. The method was further applied to over 500 real soil and sediment samples. 2,4-D and fipronil concentrations varied from 0.03 to 1145 µg kg-1 and 1.1 to 282 µg kg-1, respectively.
{"title":"Influence of the Soil Composition on the Determination of 2,4-D and Fipronil in Environmental Samples by SLE-LC-MS/MS","authors":"B. Goulart, B. Vizioli, Evaldo Luiz Espindola, C. Montagner","doi":"10.21577/0103-5053.20230126","DOIUrl":"https://doi.org/10.21577/0103-5053.20230126","url":null,"abstract":"The main objective of this work was to develop and validate an analytical method using solid-liquid extraction and liquid chromatography coupled with mass spectrometry in tandem (LC-MS/MS) for the simultaneous determination of the herbicide 2-(2,4-dichlorophenoxy)acetic acid (2,4-D) and the insecticide fipronil and its degradation products, fipronil sulfone and fipronil sulfide in different types of soil from Brazil (Oxisol and Entisol). Solid-liquid extraction was performed in two cycles using 20 mL of dichloromethane per cycle and sonication. The extraction efficiency of 2,4-D was more influenced by soil composition than the other compounds. The limits of quantification of the method were between 0.015 and 0.75 mg kg-1 and recovery values from 61 to 118%, with a maximum relative standard deviation (RSD) value of 4%. The method was further applied to over 500 real soil and sediment samples. 2,4-D and fipronil concentrations varied from 0.03 to 1145 µg kg-1 and 1.1 to 282 µg kg-1, respectively.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68340234","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 : 2023-10-23DOI: 10.21577/0103-5053.20230091
Taynara Matos, M. Marques, C. Chaves, Flávia S. Zandonadi, C. Palma‐Silva, Alessandra Sussulini
The aim of this study was to preliminary evaluate the lipid profile alterations on Pitcairnia flammea leaves based on variations in solvent proportion and ultrasonic ice bath extraction time, followed by a lipid class-enriched analysis employing chemometric techniques. Ultra-high performance liquid chromatography coupled to electrospray ionization mass spectrometry (UHPLC-ESI-MS) was used to acquire raw data and MS-DIAL and MetaboAnalyst platforms were used to perform data preprocessing and statistical analysis. The statistical analysis of UHPLC-ESI-MS data in both ionization modes enabled the visualization of a trend distribution based on extraction time. Furthermore, we were able to establish that the solvent proportion had a greater impact on group separation in data samples extracted for 30 min versus 10 and 20 min. Moreover, diacylglycerol or/and lysophosphatidylcholine are lipid subclasses that can be favored depending on the extraction time in the mass spectrometry analyses using positive electrospray ionization mode.
{"title":"Evaluation of Extraction Parameters for the Analysis of Lipid Classes in Plants","authors":"Taynara Matos, M. Marques, C. Chaves, Flávia S. Zandonadi, C. Palma‐Silva, Alessandra Sussulini","doi":"10.21577/0103-5053.20230091","DOIUrl":"https://doi.org/10.21577/0103-5053.20230091","url":null,"abstract":"The aim of this study was to preliminary evaluate the lipid profile alterations on Pitcairnia flammea leaves based on variations in solvent proportion and ultrasonic ice bath extraction time, followed by a lipid class-enriched analysis employing chemometric techniques. Ultra-high performance liquid chromatography coupled to electrospray ionization mass spectrometry (UHPLC-ESI-MS) was used to acquire raw data and MS-DIAL and MetaboAnalyst platforms were used to perform data preprocessing and statistical analysis. The statistical analysis of UHPLC-ESI-MS data in both ionization modes enabled the visualization of a trend distribution based on extraction time. Furthermore, we were able to establish that the solvent proportion had a greater impact on group separation in data samples extracted for 30 min versus 10 and 20 min. Moreover, diacylglycerol or/and lysophosphatidylcholine are lipid subclasses that can be favored depending on the extraction time in the mass spectrometry analyses using positive electrospray ionization mode.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68339164","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 : 2023-10-23DOI: 10.21577/0103-5053.20230132
Gesline de Almeida, A. Chaves, Maria Eugênia Queiroz, K. Gramacho, L. Gonçalves
Pheromones are essential for colony organization in honeybees. The pheromones 9-ODA ((E)-9-oxodec-2-enoic acid) and 9-HDA ((E)-9-hydroxydec-2-enoic acid), produced by the mandibular gland of the queen, have various functions within the colony, including inhibition of ovarian development of workers, attraction of swarms, and stabilization of the cluster group. An example of reaction of the colony to adverse conditions is absconding, which is defined as mass exit of all of the adult individuals, leaving even brood and food. In this study, the pheromones 9-ODA and 9-HDA were determined in virgin and normal mated, egg-laying European Carniolan and Africanized queens, as well as in mated queens that were in absconding colonies, using liquid chromatography with UV detection developed methodology. Absconding was induced by maintaining free-flying five-standard-Langstroth-frame colonies in a chamber artificially heated to 45 ºC. The obtained results showed that the amount of 9-ODA in Africanized queens (6.56 µg bee-1 ) is very low compared with European queens. However, large amounts of 9-HDA were found in the queens of absconding Africanized swarms (107.4 µg bee-1). According to our results, the quantities of 9-ODA and 9-HDA in Africanized honeybees in Brazil may be contributing to the high rates of absconding, promoting low effect of stabilizing agent, and high effect of attraction of dispersers cluster.
{"title":"Evaluation of the Mandibular Pheromones Produced by Queens of Africanized and European Honeybees under Normal Conditions and During Absconding Processes by HPLC-UV Methodology","authors":"Gesline de Almeida, A. Chaves, Maria Eugênia Queiroz, K. Gramacho, L. Gonçalves","doi":"10.21577/0103-5053.20230132","DOIUrl":"https://doi.org/10.21577/0103-5053.20230132","url":null,"abstract":"Pheromones are essential for colony organization in honeybees. The pheromones 9-ODA ((E)-9-oxodec-2-enoic acid) and 9-HDA ((E)-9-hydroxydec-2-enoic acid), produced by the mandibular gland of the queen, have various functions within the colony, including inhibition of ovarian development of workers, attraction of swarms, and stabilization of the cluster group. An example of reaction of the colony to adverse conditions is absconding, which is defined as mass exit of all of the adult individuals, leaving even brood and food. In this study, the pheromones 9-ODA and 9-HDA were determined in virgin and normal mated, egg-laying European Carniolan and Africanized queens, as well as in mated queens that were in absconding colonies, using liquid chromatography with UV detection developed methodology. Absconding was induced by maintaining free-flying five-standard-Langstroth-frame colonies in a chamber artificially heated to 45 ºC. The obtained results showed that the amount of 9-ODA in Africanized queens (6.56 µg bee-1 ) is very low compared with European queens. However, large amounts of 9-HDA were found in the queens of absconding Africanized swarms (107.4 µg bee-1). According to our results, the quantities of 9-ODA and 9-HDA in Africanized honeybees in Brazil may be contributing to the high rates of absconding, promoting low effect of stabilizing agent, and high effect of attraction of dispersers cluster.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68340310","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 : 2023-10-23DOI: 10.21577/0103-5053.20230086
Isabela Ambrosio, A. Santos, A. Faria
The physical adsorption of a polymer, poly(3,3,3-trifluoropropylmethylsiloxane), on aluminized silica particles, without any additional procedure for polymer immobilization, was studied for 180 days to evaluate the new chromatographic support. Morphological, structural, and chromatographic evaluations of the stationary phase were assessed. After the 15th day of adsorption, a sufficient polymer amount adsorbs onto the aluminized silica particles to separate mixtures of compounds in reversed-phase mode. However, after the 60th day, the polymer layer adhesion occurs more strongly, self-coating the aluminized silica particles. The self-coated stationary phases after 60 days showed similar chromatographic profiles with low hydrophobicity and more interactions with polar compounds, characteristics arising from the fluorinated polymer. The aluminized silica support firmly adhered to the polymer layer, resulting in a separation material chemically stable at alkaline conditions, suggesting a surface reactivity like other well-established supports without asymmetrical peaks for polar compounds.
{"title":"Evaluation of Polymer Self-Coating on Aluminized Silica Support as Stationary Phase for High-Performance Liquid Chromatography","authors":"Isabela Ambrosio, A. Santos, A. Faria","doi":"10.21577/0103-5053.20230086","DOIUrl":"https://doi.org/10.21577/0103-5053.20230086","url":null,"abstract":"The physical adsorption of a polymer, poly(3,3,3-trifluoropropylmethylsiloxane), on aluminized silica particles, without any additional procedure for polymer immobilization, was studied for 180 days to evaluate the new chromatographic support. Morphological, structural, and chromatographic evaluations of the stationary phase were assessed. After the 15th day of adsorption, a sufficient polymer amount adsorbs onto the aluminized silica particles to separate mixtures of compounds in reversed-phase mode. However, after the 60th day, the polymer layer adhesion occurs more strongly, self-coating the aluminized silica particles. The self-coated stationary phases after 60 days showed similar chromatographic profiles with low hydrophobicity and more interactions with polar compounds, characteristics arising from the fluorinated polymer. The aluminized silica support firmly adhered to the polymer layer, resulting in a separation material chemically stable at alkaline conditions, suggesting a surface reactivity like other well-established supports without asymmetrical peaks for polar compounds.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68339362","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 : 2023-10-23DOI: 10.21577/0103-5053.20230120
I. D. dos Santos, P. Lucena, A. Moraes, Jhonattas C Carregosa, T. Santos, Alberto Wisniewski Jr., J. Santos
In 2019, large amounts of oil reached the northeast coast of Brazil, causing damage to the environment and the local economy, especially in the state of Pernambuco. In order to correlate with possible sources, investigation was made of the geochemical biomarkers of the oils using “gold standard” forensic protocols from the European Committee for Standardization (CEN). The biomarkers study was improved by using gas chromatography-tandem mass spectrometry (GC-MS/MS), rather than the standard protocol that suggests use of the selected ion monitoring (SIM) method. Analysis was made of thirteen oil samples from the Pernambuco coast, in order to identify their degrees of similarity and the possible presence of oils from unreported spills. The use of eighteen diagnostic ratios and multivariate analysis revealed a cluster formed by eleven samples with biomarker distributions typical of oil from the 2019 spill. However, two samples had anomalous fingerprints, especially due to the absence of the 18α(H)-oleanane and 18β(H)-oleanane isomers. Both the CEN protocol applied for the classical biomarkers and a comprehensive Fourier transform mass spectrometry (FT-MS) analysis of polar compounds confirmed the dissimilarities between the samples. The findings suggested that these two oils could have originated from an event unrelated to the mysterious 2019 spill.
{"title":"Biomarkers Profile of the Mysterious 2019 Oil Spill on the Northeast Coast of Brazil and Discrimination from Unreported Events","authors":"I. D. dos Santos, P. Lucena, A. Moraes, Jhonattas C Carregosa, T. Santos, Alberto Wisniewski Jr., J. Santos","doi":"10.21577/0103-5053.20230120","DOIUrl":"https://doi.org/10.21577/0103-5053.20230120","url":null,"abstract":"In 2019, large amounts of oil reached the northeast coast of Brazil, causing damage to the environment and the local economy, especially in the state of Pernambuco. In order to correlate with possible sources, investigation was made of the geochemical biomarkers of the oils using “gold standard” forensic protocols from the European Committee for Standardization (CEN). The biomarkers study was improved by using gas chromatography-tandem mass spectrometry (GC-MS/MS), rather than the standard protocol that suggests use of the selected ion monitoring (SIM) method. Analysis was made of thirteen oil samples from the Pernambuco coast, in order to identify their degrees of similarity and the possible presence of oils from unreported spills. The use of eighteen diagnostic ratios and multivariate analysis revealed a cluster formed by eleven samples with biomarker distributions typical of oil from the 2019 spill. However, two samples had anomalous fingerprints, especially due to the absence of the 18α(H)-oleanane and 18β(H)-oleanane isomers. Both the CEN protocol applied for the classical biomarkers and a comprehensive Fourier transform mass spectrometry (FT-MS) analysis of polar compounds confirmed the dissimilarities between the samples. The findings suggested that these two oils could have originated from an event unrelated to the mysterious 2019 spill.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68340019","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 : 2023-10-23DOI: 10.21577/0103-5053.20230088
Luciane Effting, Alesandro Bail, M. Segatelli, C. Tarley
In the present study, a novel magnetic dispersive solid-phase extraction method using molecularly imprinted polymer synthesized through semi-covalent imprinting approach was developed for cholesterol (CHO) determination in milk samples by high-performance liquid chromatography with diode array detector (HPLC-DAD). The adsorbent named Fe3O4/SiO2/MIP (MIP: molecularly imprinted polymers) was prepared through sol-gel polymerization of 3-(triethoxysilyl)propyl isocyanate (ICPTES) covalently bonded to CHO with tetraethoxysilane (TEOS), in the presence of Fe3O4/SiO2 particles. The adsorbent was characterized by attenuated total reflection Fourier transform infrared (ATR-FTIR), X-ray diffraction (XRD), dynamic light scattering (DLS) and scanning electron microscopy (SEM). The proposed molecularly imprinted polymer-based magnetic dispersive solid-phase extraction method (MIP-MDSPE) was based on vortex-assisted preconcentration of 10.0 mL of CHO solution in chloroform as donor phase using 10.0 mg of Fe3O4/SiO2/MIP during 60 s. After this step, the magnetic particles were collected using a permanent magnet and the vortex-assisted elution was carried with 500 µL of ethanol during 180 s. A wide analytical curve ranging from 38.5 to 25000 µg L-1 (determination coefficient (R2 ) = 0.998) and low limits of detection (LOD) and quantification (LOQ) 11.5 and 38.5 µg L-1, respectively, were obtained. Milk samples (whole and reduced-fat milk) were subjected to MIP-MDSPE method after saponification reaction followed by CHO extraction with chloroform. Using external calibration, the CHO concentration ranged from 99.2 (reduced-fat milk) to 397.6 mg kg-1 (whole milk) and the accuracy was attested by addition and recovery tests (92 to 97%).
{"title":"Development of a Novel Sensitive and Fast Semi-Covalent Molecularly Imprinted Polymer-Based Magnetic Dispersive Solid-Phase Extraction Method (MIP-MDSPE) for Cholesterol Determination in Milk Samples","authors":"Luciane Effting, Alesandro Bail, M. Segatelli, C. Tarley","doi":"10.21577/0103-5053.20230088","DOIUrl":"https://doi.org/10.21577/0103-5053.20230088","url":null,"abstract":"In the present study, a novel magnetic dispersive solid-phase extraction method using molecularly imprinted polymer synthesized through semi-covalent imprinting approach was developed for cholesterol (CHO) determination in milk samples by high-performance liquid chromatography with diode array detector (HPLC-DAD). The adsorbent named Fe3O4/SiO2/MIP (MIP: molecularly imprinted polymers) was prepared through sol-gel polymerization of 3-(triethoxysilyl)propyl isocyanate (ICPTES) covalently bonded to CHO with tetraethoxysilane (TEOS), in the presence of Fe3O4/SiO2 particles. The adsorbent was characterized by attenuated total reflection Fourier transform infrared (ATR-FTIR), X-ray diffraction (XRD), dynamic light scattering (DLS) and scanning electron microscopy (SEM). The proposed molecularly imprinted polymer-based magnetic dispersive solid-phase extraction method (MIP-MDSPE) was based on vortex-assisted preconcentration of 10.0 mL of CHO solution in chloroform as donor phase using 10.0 mg of Fe3O4/SiO2/MIP during 60 s. After this step, the magnetic particles were collected using a permanent magnet and the vortex-assisted elution was carried with 500 µL of ethanol during 180 s. A wide analytical curve ranging from 38.5 to 25000 µg L-1 (determination coefficient (R2 ) = 0.998) and low limits of detection (LOD) and quantification (LOQ) 11.5 and 38.5 µg L-1, respectively, were obtained. Milk samples (whole and reduced-fat milk) were subjected to MIP-MDSPE method after saponification reaction followed by CHO extraction with chloroform. Using external calibration, the CHO concentration ranged from 99.2 (reduced-fat milk) to 397.6 mg kg-1 (whole milk) and the accuracy was attested by addition and recovery tests (92 to 97%).","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":"35 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68339467","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 : 2023-10-23DOI: 10.21577/0103-5053.20230103
J. Ferreira, Nayara A Dos Santos, K. Borges, Nathália Conceição, Clara Baptista, H. França, W. Romão
Among stimulant drugs, cocaine deserves attention due to its high rates of seizures worldwide. This work presents the synthesis and characterization of hybrid molecularly imprinted polymers (MIPs) for use in preparing biological samples using a homemade microextraction in a packed sorbent device to extract cocaine. The MIPs synthesized using caffeine and cocaine as templates have been compared. Caffeine was used due to its low value and be easier to obtain than cocaine. Additionally, restricted access molecularly imprinted polymers (RAMIPs) were also produced for comparison purposes. The polymeric materials were characterized using scanning electron microscopy, textural analysis, Fourier transform infrared spectroscopy, and cross polarization/ magic angle spinning 13C nuclear magnetic resonance. The method optimization was performed using linear ion trap mass spectrometer to evaluate the effects of sample pH, type of eluent, washing solvent, adsorption cycles, and eluent volume. In the optimized method, RAMIPs indicated better cocaine extraction compared to MIPs. The quantitative study demonstrated that the developed method was able to accurately quantify cocaine in urine samples with values close to actual concentrations.
{"title":"Synthesis and Characterization of Molecularly Imprinted Polymers for the Determination of Cocaine in Urine Using Microextraction in Packed Sorvent","authors":"J. Ferreira, Nayara A Dos Santos, K. Borges, Nathália Conceição, Clara Baptista, H. França, W. Romão","doi":"10.21577/0103-5053.20230103","DOIUrl":"https://doi.org/10.21577/0103-5053.20230103","url":null,"abstract":"Among stimulant drugs, cocaine deserves attention due to its high rates of seizures worldwide. This work presents the synthesis and characterization of hybrid molecularly imprinted polymers (MIPs) for use in preparing biological samples using a homemade microextraction in a packed sorbent device to extract cocaine. The MIPs synthesized using caffeine and cocaine as templates have been compared. Caffeine was used due to its low value and be easier to obtain than cocaine. Additionally, restricted access molecularly imprinted polymers (RAMIPs) were also produced for comparison purposes. The polymeric materials were characterized using scanning electron microscopy, textural analysis, Fourier transform infrared spectroscopy, and cross polarization/ magic angle spinning 13C nuclear magnetic resonance. The method optimization was performed using linear ion trap mass spectrometer to evaluate the effects of sample pH, type of eluent, washing solvent, adsorption cycles, and eluent volume. In the optimized method, RAMIPs indicated better cocaine extraction compared to MIPs. The quantitative study demonstrated that the developed method was able to accurately quantify cocaine in urine samples with values close to actual concentrations.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68339858","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 : 2023-10-23DOI: 10.21577/0103-5053.20230109
Fábio de Matos, G. D. de Carvalho, O. Prestes, M. Adaime, R. Zanella
The herbicide glyphosate is the most widely used pesticide worldwide. Glyphosate and its major metabolite, aminomethylphosphonic acid (AMPA), have been frequently found in water samples. The widely used methods for determining these compounds are expensive and environmentally unfriendly due to reagent consumption for derivatization. Another possibility is the use of classic ion chromatography, albeit with low sensitivity and subject to interferences. Therefore, this study aimed to develop a method to directly and simultaneously determine glyphosate, AMPA, and common inorganic anions in water samples using gradient capillary ion chromatography without sample pre-treatment and derivatization. The proposed method was validated, presenting adequate linearity for glyphosate and AMPA with a determination coefficient (r2 ) > 0.998. Recoveries ranged from 94 to 105% and 79 to 113% for glyphosate and AMPA, respectively, with a relative standard deviation < 10%. The practical method limits of detection and quantification for both glyphosate and AMPA were 7.5 and 25 µg L-1, respectively. The method presented satisfactory results for the anions fluoride, chloride, bromide, nitrite, nitrate, phosphate, and sulfate, with limits of detection ranging from 7.5 to 200 µg L-1. Application of the method in water samples proved simple, efficient, and cost-effective, enabling the monitoring of these analytes in different water matrices.
{"title":"Simultaneous Determination of Glyphosate, AMPA and Inorganic Anions in Water Samples by Gradient Capillary Ion Chromatography","authors":"Fábio de Matos, G. D. de Carvalho, O. Prestes, M. Adaime, R. Zanella","doi":"10.21577/0103-5053.20230109","DOIUrl":"https://doi.org/10.21577/0103-5053.20230109","url":null,"abstract":"The herbicide glyphosate is the most widely used pesticide worldwide. Glyphosate and its major metabolite, aminomethylphosphonic acid (AMPA), have been frequently found in water samples. The widely used methods for determining these compounds are expensive and environmentally unfriendly due to reagent consumption for derivatization. Another possibility is the use of classic ion chromatography, albeit with low sensitivity and subject to interferences. Therefore, this study aimed to develop a method to directly and simultaneously determine glyphosate, AMPA, and common inorganic anions in water samples using gradient capillary ion chromatography without sample pre-treatment and derivatization. The proposed method was validated, presenting adequate linearity for glyphosate and AMPA with a determination coefficient (r2 ) > 0.998. Recoveries ranged from 94 to 105% and 79 to 113% for glyphosate and AMPA, respectively, with a relative standard deviation < 10%. The practical method limits of detection and quantification for both glyphosate and AMPA were 7.5 and 25 µg L-1, respectively. The method presented satisfactory results for the anions fluoride, chloride, bromide, nitrite, nitrate, phosphate, and sulfate, with limits of detection ranging from 7.5 to 200 µg L-1. Application of the method in water samples proved simple, efficient, and cost-effective, enabling the monitoring of these analytes in different water matrices.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68340129","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: 10.21577/0103-5053.20230056
L. Azevedo, B. Andrade-da-Costa, R. Augusto, L. Luz, I. de Souza, Licarion Pinto, I. Alves, S. Alves Júnior
In the present study, we tested the proof of concept that mobil mesoporous silica nanoparticle composition of matter (MCM) No. 48 doped with trivalent europium (nanoMCM48:Eu3+) administered systemically intravenously can act as a suitable vehicle to deliver neural cells to the brain of healthy adult Swiss mice without causing tissue damage. Moreover, we also tested the ability of this nanoparticle to release molecules in vitro, using as drug models caffeine or nicotine in phosphate buffer solution with pH 7.4 adequate to intra and extra-celular medium of the brain. The caffeine and nicotine adsorbed nanoparticles (CAF@MCM48:Eu3+ and NIC@MCM48:Eu3+) were observed in the parenchyma of the cerebral cortex and diffusely dispersed in the cellular cytoplasm. Statistical analysis using multivariate partner recognition methods indicated that there was no sign of cell damage, as it was characterized by chromatin condensation, nuclear condensation, or fragmentation. The characterization of nanoMCM48:Eu3+ as particle size, luminescent properties and release of active components were analyzed. The CAF@MCM48:Eu3+ and NIC@MCM48:Eu3+ nanoparticles were observed in the cerebral cortex parenchyma and diffusely dispersed in the cell cytoplasm, and the release of active components was analyzed. Therefore, the studies showed that mesoporous silica nanoparticles administered systemically via intravenous tissue can act as a suitable vehicle for neural cells in the brain of healthy mice without causing damage.
{"title":"Design and Evaluation of Systemic Administration of Nano Silica MCM48:Eu3+ in Mouse Brain","authors":"L. Azevedo, B. Andrade-da-Costa, R. Augusto, L. Luz, I. de Souza, Licarion Pinto, I. Alves, S. Alves Júnior","doi":"10.21577/0103-5053.20230056","DOIUrl":"https://doi.org/10.21577/0103-5053.20230056","url":null,"abstract":"In the present study, we tested the proof of concept that mobil mesoporous silica nanoparticle composition of matter (MCM) No. 48 doped with trivalent europium (nanoMCM48:Eu3+) administered systemically intravenously can act as a suitable vehicle to deliver neural cells to the brain of healthy adult Swiss mice without causing tissue damage. Moreover, we also tested the ability of this nanoparticle to release molecules in vitro, using as drug models caffeine or nicotine in phosphate buffer solution with pH 7.4 adequate to intra and extra-celular medium of the brain. The caffeine and nicotine adsorbed nanoparticles (CAF@MCM48:Eu3+ and NIC@MCM48:Eu3+) were observed in the parenchyma of the cerebral cortex and diffusely dispersed in the cellular cytoplasm. Statistical analysis using multivariate partner recognition methods indicated that there was no sign of cell damage, as it was characterized by chromatin condensation, nuclear condensation, or fragmentation. The characterization of nanoMCM48:Eu3+ as particle size, luminescent properties and release of active components were analyzed. The CAF@MCM48:Eu3+ and NIC@MCM48:Eu3+ nanoparticles were observed in the cerebral cortex parenchyma and diffusely dispersed in the cell cytoplasm, and the release of active components was analyzed. Therefore, the studies showed that mesoporous silica nanoparticles administered systemically via intravenous tissue can act as a suitable vehicle for neural cells in the brain of healthy mice without causing damage.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68336194","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: 10.21577/0103-5053.20230057
M. Gonçalves, Cleiton Nunes, T. Sáfadi, Teodorico C. Ramalho
Wavepress is a signal processing software that has a simple and friendly interface that can be used by researchers, professors and students. The program uses the wavelet transform, which is a signal processing tool, being used to handle a signal in the time-scale space. In this way, the program can be used for signal processing capable of reducing, without losing important information, the amount of information. Thus, it is possible to obtain graphs and tables to explore the results in a comprehensive and satisfying way. In this work, the main features of Wavepress are explored with applications in computational chemistry, and drug design, all examples are illustrated with graphs and tables got with Wavepress.
{"title":"Wavepress is a User-Friendly Toolkit for Computational Chemistry, Drug Design and Material Science","authors":"M. Gonçalves, Cleiton Nunes, T. Sáfadi, Teodorico C. Ramalho","doi":"10.21577/0103-5053.20230057","DOIUrl":"https://doi.org/10.21577/0103-5053.20230057","url":null,"abstract":"Wavepress is a signal processing software that has a simple and friendly interface that can be used by researchers, professors and students. The program uses the wavelet transform, which is a signal processing tool, being used to handle a signal in the time-scale space. In this way, the program can be used for signal processing capable of reducing, without losing important information, the amount of information. Thus, it is possible to obtain graphs and tables to explore the results in a comprehensive and satisfying way. In this work, the main features of Wavepress are explored with applications in computational chemistry, and drug design, all examples are illustrated with graphs and tables got with Wavepress.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68336275","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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