Pub Date : 2022-08-03DOI: 10.30744/brjac.2179-3425.ar-21-2022
Ana Karolina Costa, J. Senna, Larissa Cardoso, L. Palermo, C. Mansur
Flamboyant mirim gum is a galactomannan, extracted from Caesalpinia pulcherrima seeds, a legume family schrub. The main objective of this work was to propose a factorial experimental design to optimize the galactomannan extraction process from its seeds and evaluate its potential as a viscosifying agent for enhanced oil recovery (EOR). The galactomannan was characterized by FTIR, NMR, SEC, thermogravimetric analysis, elemental analysis, and rheology. Structural analyses confirmed the presence of the desired galactomannan content. The best yield obtained was 7.3% for initial seed mass and 24.6% for the endosperm. Rheological analysis showed that Flamboyant mirim gum is a promising alternative for EOR application in high salinity conditions. In addition, stability tests showed that glutaraldehyde can be considered a promising biocide for fluids containing galactomannan since it maintained the viscosity values of the systems for 42 days. Thus, the results confirmed the adequacy of the extraction procedure for obtaining galactomannan.
{"title":"Extraction and Evaluation of Flamboyant Mirim Gum as a Potential Viscosifying Agent for Enhanced Oil Recovery Fluids","authors":"Ana Karolina Costa, J. Senna, Larissa Cardoso, L. Palermo, C. Mansur","doi":"10.30744/brjac.2179-3425.ar-21-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-21-2022","url":null,"abstract":"Flamboyant mirim gum is a galactomannan, extracted from Caesalpinia pulcherrima seeds, a legume family schrub. The main objective of this work was to propose a factorial experimental design to optimize the galactomannan extraction process from its seeds and evaluate its potential as a viscosifying agent for enhanced oil recovery (EOR). The galactomannan was characterized by FTIR, NMR, SEC, thermogravimetric analysis, elemental analysis, and rheology. Structural analyses confirmed the presence of the desired galactomannan content. The best yield obtained was 7.3% for initial seed mass and 24.6% for the endosperm. Rheological analysis showed that Flamboyant mirim gum is a promising alternative for EOR application in high salinity conditions. In addition, stability tests showed that glutaraldehyde can be considered a promising biocide for fluids containing galactomannan since it maintained the viscosity values of the systems for 42 days. Thus, the results confirmed the adequacy of the extraction procedure for obtaining galactomannan.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43909451","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 : 2022-08-01DOI: 10.30744/brjac.2179-3425.ar-17-2022
C. Ramos, Daysnan dos Santos, Líbna Claudino, J. de Albuquerque, Marcílio Silva
A simple method was developed to obtain and fractionate essential oil simultaneously by hydrodistillation. With this method it was possible to obtain essential oils from the leaves of Piper arboreum with the cadinol content ranging from 17.7 to 57.9%. In the essential oils from the leaves of P. aduncum was identified dillapiole with content ranging from 4.6 to 96.9%; and further, essential oil from P. marginatum with the presence of phenylpropanoids as minor compounds. The essential oils of the three Piper species varied in antimicrobial activity when fractionated, with P. marginatum oil exhibiting the lowest minimum inhibitory concentration at 19.5 µg mL-1 for the Pseudomonas aeruginosa bacterium. The method was efficient for the separation and concentration of chemical constituents of essential oils from the same plant, able to distinguish the different chemical profiles, both qualitatively and quantitatively.
{"title":"Use of Hydrodistillation to Obtain and Fractionate Essential Oils Simultaneously","authors":"C. Ramos, Daysnan dos Santos, Líbna Claudino, J. de Albuquerque, Marcílio Silva","doi":"10.30744/brjac.2179-3425.ar-17-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-17-2022","url":null,"abstract":"A simple method was developed to obtain and fractionate essential oil simultaneously by hydrodistillation. With this method it was possible to obtain essential oils from the leaves of Piper arboreum with the cadinol content ranging from 17.7 to 57.9%. In the essential oils from the leaves of P. aduncum was identified dillapiole with content ranging from 4.6 to 96.9%; and further, essential oil from P. marginatum with the presence of phenylpropanoids as minor compounds. The essential oils of the three Piper species varied in antimicrobial activity when fractionated, with P. marginatum oil exhibiting the lowest minimum inhibitory concentration at 19.5 µg mL-1 for the Pseudomonas aeruginosa bacterium. The method was efficient for the separation and concentration of chemical constituents of essential oils from the same plant, able to distinguish the different chemical profiles, both qualitatively and quantitatively.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44575072","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 : 2022-08-01DOI: 10.30744/brjac.2179-3425.ar-47-2022
N. Agrawal, Shilpi Pathak
Evogliptin (EGT) is used in fixed-dose combination with metformin hydrochloride (MFH) for a better glycemic control in Type 2 diabetes mellitus. To date, no method is available for simultaneous estimation of these drugs. In the present study, an UV spectrophotometric method was developed in distilled water, an environment-friendly solvent using the simultaneous equation technique to simultaneously determine EGT and MFH in bulk and tablet dosage form. The developed method was validated and applied to commercial tablet dosage forms containing EGT and MFH in combination. With a great correlation value (R2>0.998), the analytes displayed good linearity in the range of 10-100 μg mL-1. The low percent relative standard deviation proved the methods' precision. The methods' accuracy was demonstrated by excellent recovery. Thus, the developed method was found to be simple, environment-friendly, fast, specific, precise, and accurate, and it may be effectively used for routine analysis of EGT and MFH in bulk and their combined tablet dosage form.
{"title":"Eco-Friendly UV Spectrophotometric Method for Simultaneous Estimation of Evogliptin and Metformin Hydrochloride in Bulk and Combined Tablet Dosage Form","authors":"N. Agrawal, Shilpi Pathak","doi":"10.30744/brjac.2179-3425.ar-47-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-47-2022","url":null,"abstract":"Evogliptin (EGT) is used in fixed-dose combination with metformin hydrochloride (MFH) for a better glycemic control in Type 2 diabetes mellitus. To date, no method is available for simultaneous estimation of these drugs. In the present study, an UV spectrophotometric method was developed in distilled water, an environment-friendly solvent using the simultaneous equation technique to simultaneously determine EGT and MFH in bulk and tablet dosage form. The developed method was validated and applied to commercial tablet dosage forms containing EGT and MFH in combination. With a great correlation value (R2>0.998), the analytes displayed good linearity in the range of 10-100 μg mL-1. The low percent relative standard deviation proved the methods' precision. The methods' accuracy was demonstrated by excellent recovery. Thus, the developed method was found to be simple, environment-friendly, fast, specific, precise, and accurate, and it may be effectively used for routine analysis of EGT and MFH in bulk and their combined tablet dosage form.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48044527","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 : 2022-07-11DOI: 10.30744/brjac.2179-3425.ar-16-2022
Danielle Francischini, R. Amais, N. Stríkis, M. Arruda
The laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) technique is considered versatile for multi-elemental analysis and imaging because it is easy to handle, compatible with different types of solid samples, requires minimal sample preparation, and provides high spatial resolution and sensitivity. One of the challenges of imaging analysis is to obtain accurate and precise spatial information of elements distribution in the sample, so the optimization of the laser ablation (LA) parameters is essential. In this context, this study aimed to optimize the LA parameters for direct analysis of speleothem samples. Laser intensity, frequency, and spot diameter were evaluated through multivariate experimental design and multi-response data, the influence of ablation scan speed and the use of 44Ca as an internal standard (IS) for the qualitative image of 66Zn, 137Ba, 55Mn, 57Fe, 88Sr, 60Ni, and 26Mg distribution in the sample were also evaluated. The multivariate optimization revealed positive interactions between the parameters evaluated, i.e., the greater the laser intensity, LA frequency, and spot diameter, the greater the analyte signal and, thus the sensitivity. Therefore, 90% laser ablation intensity, 20 Hz repetition rate, and 100 µm spot diameter were selected. In the scan speed evaluation, the images obtained with 40 and 20 µm s-1 were very similar for all isotopes. The use of 44Ca as IS did not impact the resolution of the images. The use of 44Ca can provide important information about the speleothem formation and paleoclimate changes.
{"title":"Qualitative imaging of elemental spatial distribution in stalagmites through laser ablation inductively coupled plasma mass spectrometry analysis","authors":"Danielle Francischini, R. Amais, N. Stríkis, M. Arruda","doi":"10.30744/brjac.2179-3425.ar-16-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-16-2022","url":null,"abstract":"The laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) technique is considered versatile for multi-elemental analysis and imaging because it is easy to handle, compatible with different types of solid samples, requires minimal sample preparation, and provides high spatial resolution and sensitivity. One of the challenges of imaging analysis is to obtain accurate and precise spatial information of elements distribution in the sample, so the optimization of the laser ablation (LA) parameters is essential. In this context, this study aimed to optimize the LA parameters for direct analysis of speleothem samples. Laser intensity, frequency, and spot diameter were evaluated through multivariate experimental design and multi-response data, the influence of ablation scan speed and the use of 44Ca as an internal standard (IS) for the qualitative image of 66Zn, 137Ba, 55Mn, 57Fe, 88Sr, 60Ni, and 26Mg distribution in the sample were also evaluated. The multivariate optimization revealed positive interactions between the parameters evaluated, i.e., the greater the laser intensity, LA frequency, and spot diameter, the greater the analyte signal and, thus the sensitivity. Therefore, 90% laser ablation intensity, 20 Hz repetition rate, and 100 µm spot diameter were selected. In the scan speed evaluation, the images obtained with 40 and 20 µm s-1 were very similar for all isotopes. The use of 44Ca as IS did not impact the resolution of the images. The use of 44Ca can provide important information about the speleothem formation and paleoclimate changes.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46730642","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 : 2022-06-27DOI: 10.30744/brjac.2179-3425.ar-14-2022
Letícia Leonardelli, S. Leonardelli, J. Schwambach
The Brazilian blueberry (Vaccinium spp.) production has made remarkable progress in developing quality and quantity. The price of the fruit for fresh and processing purposes is linked to its quality and origin. An effective method for authenticity control and traceability is the stable isotopes method. Carbon (13C) and oxygen (18O) of Brazilian blueberries have never been extensively explored. In this work, the results of 13C and 18O (performed by IRMS) of thirty blueberry samples were presented and discussed, being eleven different cultivars produced in the Southern Brazilian region from mountain and high-altitude. The blueberry showed the typical range of carbon isotopes for C3 plants, with significant differences between Rabbiteye and Southern Highbush. The δ13C and δ18O values showed a significant difference between a mountain and a high-altitude region. This study represents the first isotopic database for Brazilian blueberries, and it can be incorporated into a traceability system. In addition, these results can be used to verify the authenticity of the fruit composition declared on the label and as an effective tool for identifying the geographical origin.
{"title":"Carbon and Oxygen Isotope Profile in Brazilian Blueberries (Vaccinium spp.)","authors":"Letícia Leonardelli, S. Leonardelli, J. Schwambach","doi":"10.30744/brjac.2179-3425.ar-14-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-14-2022","url":null,"abstract":"The Brazilian blueberry (Vaccinium spp.) production has made remarkable progress in developing quality and quantity. The price of the fruit for fresh and processing purposes is linked to its quality and origin. An effective method for authenticity control and traceability is the stable isotopes method. Carbon (13C) and oxygen (18O) of Brazilian blueberries have never been extensively explored. In this work, the results of 13C and 18O (performed by IRMS) of thirty blueberry samples were presented and discussed, being eleven different cultivars produced in the Southern Brazilian region from mountain and high-altitude. The blueberry showed the typical range of carbon isotopes for C3 plants, with significant differences between Rabbiteye and Southern Highbush. The δ13C and δ18O values showed a significant difference between a mountain and a high-altitude region. This study represents the first isotopic database for Brazilian blueberries, and it can be incorporated into a traceability system. In addition, these results can be used to verify the authenticity of the fruit composition declared on the label and as an effective tool for identifying the geographical origin.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46140667","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 : 2022-06-20DOI: 10.30744/brjac.2179-3425.ar-23-2022
Omar Elhamdaoui, A. El Orche, A. Cheikh, K. Laarej, K. Karrouchi, M. El Karbane, M. Bouatia
This work aims to investigate the potential of mid-infrared spectroscopy (MIR) and chemometrics algorithms for the determination of geographical origin and detection of adulteration of Moroccan saffron samples. First, the determination of the geographical origin of five saffron varieties was analyzed by linear discriminant analysis (PCA-LDA) and partial least squares discriminant analysis (PLS-DA). As a result, the developed models correctly classified saffron samples in a subset of external validation with 100% predictive ability. Next, partial least squares regression (PLS-R) was conducted to estimate the amount of adulterants (safflower) in the saffron samples. A good performance was found with Coefficient of Determination (R2) between 0.97 and 0.99. Compared to other techniques, the main advantage of the proposed methods are non-destructive, fast and sensitive which allows to achieve very precise and accurate results.
{"title":"Tracing the Geographical Origin of Moroccan Saffron by Mid-Infrared Spectroscopy and Multivariate Analysis","authors":"Omar Elhamdaoui, A. El Orche, A. Cheikh, K. Laarej, K. Karrouchi, M. El Karbane, M. Bouatia","doi":"10.30744/brjac.2179-3425.ar-23-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-23-2022","url":null,"abstract":"This work aims to investigate the potential of mid-infrared spectroscopy (MIR) and chemometrics algorithms for the determination of geographical origin and detection of adulteration of Moroccan saffron samples. First, the determination of the geographical origin of five saffron varieties was analyzed by linear discriminant analysis (PCA-LDA) and partial least squares discriminant analysis (PLS-DA). As a result, the developed models correctly classified saffron samples in a subset of external validation with 100% predictive ability. Next, partial least squares regression (PLS-R) was conducted to estimate the amount of adulterants (safflower) in the saffron samples. A good performance was found with Coefficient of Determination (R2) between 0.97 and 0.99. Compared to other techniques, the main advantage of the proposed methods are non-destructive, fast and sensitive which allows to achieve very precise and accurate results.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48729415","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 : 2022-06-02DOI: 10.30744/brjac.2179-3425.ar-04-2022
Paula Ferreira, A. D. Dos Santos, Adriana Cardoso, Paulo Almeida, J. Ribeiro, Salvador Claro Neto, A. Terezo, A. Siqueira
The industrialization has brought advances that have enabled a better quality of life for people and improved production stages and business models. However, some impacts still need to be resolved, such as water pollution. Industrial pollutants containing potentially toxic metal ions are expensive for the industry, so studying new materials and new processes has helped solve this problem. Adsorption processes using biodegradable adsorbent materials have been presented as relevant alternatives for reusing metallic ions from water bodies and sewage networks. In this perspective, tannic acid (TA) immobilization in biodegradable polyurethane (PU) foams based on vegetable oil (castor oil) was used to remove metal ions Hg (II) and Pb (II) from water. The preliminary study was carried out in TA's immobilization in PUs, with a 2k order factorial experimental design. The responses were obtained and evaluated by gravimetry and UV-Vis spectroscopy using Central Composite Design (CCD). The molar concentration of 0.1000 mol L-1 by TA solution at pH equal to 7 and 19 hours of contact time was defined as optimal conditions for TA adsorption in the PU. The optimized PU-TA system was evaluated for removing Pb (II) and Hg (II) ions in aqueous solutions, and the tests showed that 59.93% and 51.48% were removed from water, respectively. The use of the PU-TA adsorbent system for removing metals in water can be widely valuable in industrial plants that need water treatment.
{"title":"Chemometric Evaluation of a Biodegradable Tannic Acid-Polyurethane System for the Removal of Pb(II) and Hg(II) Ions from Water","authors":"Paula Ferreira, A. D. Dos Santos, Adriana Cardoso, Paulo Almeida, J. Ribeiro, Salvador Claro Neto, A. Terezo, A. Siqueira","doi":"10.30744/brjac.2179-3425.ar-04-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-04-2022","url":null,"abstract":"The industrialization has brought advances that have enabled a better quality of life for people and improved production stages and business models. However, some impacts still need to be resolved, such as water pollution. Industrial pollutants containing potentially toxic metal ions are expensive for the industry, so studying new materials and new processes has helped solve this problem. Adsorption processes using biodegradable adsorbent materials have been presented as relevant alternatives for reusing metallic ions from water bodies and sewage networks. In this perspective, tannic acid (TA) immobilization in biodegradable polyurethane (PU) foams based on vegetable oil (castor oil) was used to remove metal ions Hg (II) and Pb (II) from water. The preliminary study was carried out in TA's immobilization in PUs, with a 2k order factorial experimental design. The responses were obtained and evaluated by gravimetry and UV-Vis spectroscopy using Central Composite Design (CCD). The molar concentration of 0.1000 mol L-1 by TA solution at pH equal to 7 and 19 hours of contact time was defined as optimal conditions for TA adsorption in the PU. The optimized PU-TA system was evaluated for removing Pb (II) and Hg (II) ions in aqueous solutions, and the tests showed that 59.93% and 51.48% were removed from water, respectively. The use of the PU-TA adsorbent system for removing metals in water can be widely valuable in industrial plants that need water treatment.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44378091","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 : 2022-05-25DOI: 10.30744/brjac.2179-3425.rv-13-2022
Olívia Moreira, Jéssica Cordeiro Queiroz de Souza, J. Candido, Maria Patrícia do Nascimento, E. Penna, P. Chellini, M. D. de Oliveira
Capillary electrophoresis (CE) is an electromigration-based separation technique that emerged in the early 90s and has been evolving since then. Over recent decades, the association of CE with new technologies and detections strategies is enhancing its intrinsic mightiness. Today, CE is a part of the main high-throughput analytical platform used for medical-related applications, together with traditional gas chromatography, high-performance liquid chromatography, and fingerprinting spectroscopic methods. New strategies for assessing human disorders involve a thorough analysis of bodily fluids through said instrumentation. In this context, human urine is considered an excellent alternative, for being rich in information and easily collected with minimal inconvenience for the doners. Overall, since it is an ultrafiltrate of the human bloodstream, urine composition should be changed if any condition jeopardizes human homeostasis. Thus, monitoring the levels of biomarkers in urine by an advantageous technique such as CE can be an interesting choice for diagnostic and other clinical purposes. In this review, we will be commenting on the new tendencies and technologies applied to human urine analysis by CE over the last five years. We will be starting by commenting the applications onto target groups of molecules followed by addressing the CE feasibility for the determination of general chemical profiles through untargeted omics approaches, and finishing with the perspectives on the subject.
{"title":"Capillary Electrophoresis Applied to Human Urine Analysis for Clinical Diagnosis: New Trends and Perspectives","authors":"Olívia Moreira, Jéssica Cordeiro Queiroz de Souza, J. Candido, Maria Patrícia do Nascimento, E. Penna, P. Chellini, M. D. de Oliveira","doi":"10.30744/brjac.2179-3425.rv-13-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.rv-13-2022","url":null,"abstract":"Capillary electrophoresis (CE) is an electromigration-based separation technique that emerged in the early 90s and has been evolving since then. Over recent decades, the association of CE with new technologies and detections strategies is enhancing its intrinsic mightiness. Today, CE is a part of the main high-throughput analytical platform used for medical-related applications, together with traditional gas chromatography, high-performance liquid chromatography, and fingerprinting spectroscopic methods. New strategies for assessing human disorders involve a thorough analysis of bodily fluids through said instrumentation. In this context, human urine is considered an excellent alternative, for being rich in information and easily collected with minimal inconvenience for the doners. Overall, since it is an ultrafiltrate of the human bloodstream, urine composition should be changed if any condition jeopardizes human homeostasis. Thus, monitoring the levels of biomarkers in urine by an advantageous technique such as CE can be an interesting choice for diagnostic and other clinical purposes. In this review, we will be commenting on the new tendencies and technologies applied to human urine analysis by CE over the last five years. We will be starting by commenting the applications onto target groups of molecules followed by addressing the CE feasibility for the determination of general chemical profiles through untargeted omics approaches, and finishing with the perspectives on the subject.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49153591","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 : 2022-05-17DOI: 10.30744/brjac.2179-3425.tn-108-2021
R. Papai, Karina Torre, G. Almeida, André da Silva, Thiago Nagasima, Eduardo Jabes, Célia Santos, F. Landgraf, M. Luz
Super-magnets, materials whose strong magnetic activity is an attractive differential for the high-tech industry, may have their magnetic performance affected by small variations in their chemical composition. For example, the neodymium and praseodymium content can change the physicochemical properties of the permanent magnets. Aiming at a strict chemical quality control, this work developed an analytical method to quantify the major elements in the materials involved in the production process of didymium (the mixture of neodymium and praseodymium) super-magnets. The simultaneous determination of Nd (401.225 nm), Pr (414.311 nm), Fe (259.837 nm) and B (249.678 nm) in three different sample types (didymium oxide, metallic didymium and (Nd,Pr)-Fe-B alloy) was performed by sample dissolution in acidic media, followed by instrumental measurements using an Inductively Coupled Plasma Optical Emission Spectrometer. Linear calibration curves were obtained with high coefficient of determination (0.9983 ≤ R2 ≤ 0.9999) and with appropriate limits for determining these elements at the percentage level, reaching detection limits less than 0.07 cg g-1. The precision of the method was improved by weighing of the solutions during all the dilution steps and was evaluated by the coefficient of variation associated to instrumental precision (0.3 – 0.7%), method intermediate precision (1.9 – 3.1%) and also by the typical mass fraction provided as uncertainty (0.04 – 0.20 cg g-1), reaching the pressing need to distinguish the content of the rare earth elements in less than 1 cg g-1. The accuracy of the method was assessed by spiked and recovery test (96-104% for spikes equal to or greater than 0.50 cg g-1) and also by the use of different analytical methods, involving the participation of other laboratories, obtaining an acceptable degree of agreement (85 – 107%).
{"title":"Chemical Characterization in the Production Chain of Permanent Magnets by Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) – Precise Quantification of Nd, Pr, Fe and B in Super-Magnets Samples","authors":"R. Papai, Karina Torre, G. Almeida, André da Silva, Thiago Nagasima, Eduardo Jabes, Célia Santos, F. Landgraf, M. Luz","doi":"10.30744/brjac.2179-3425.tn-108-2021","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.tn-108-2021","url":null,"abstract":"Super-magnets, materials whose strong magnetic activity is an attractive differential for the high-tech industry, may have their magnetic performance affected by small variations in their chemical composition. For example, the neodymium and praseodymium content can change the physicochemical properties of the permanent magnets. Aiming at a strict chemical quality control, this work developed an analytical method to quantify the major elements in the materials involved in the production process of didymium (the mixture of neodymium and praseodymium) super-magnets. The simultaneous determination of Nd (401.225 nm), Pr (414.311 nm), Fe (259.837 nm) and B (249.678 nm) in three different sample types (didymium oxide, metallic didymium and (Nd,Pr)-Fe-B alloy) was performed by sample dissolution in acidic media, followed by instrumental measurements using an Inductively Coupled Plasma Optical Emission Spectrometer. Linear calibration curves were obtained with high coefficient of determination (0.9983 ≤ R2 ≤ 0.9999) and with appropriate limits for determining these elements at the percentage level, reaching detection limits less than 0.07 cg g-1. The precision of the method was improved by weighing of the solutions during all the dilution steps and was evaluated by the coefficient of variation associated to instrumental precision (0.3 – 0.7%), method intermediate precision (1.9 – 3.1%) and also by the typical mass fraction provided as uncertainty (0.04 – 0.20 cg g-1), reaching the pressing need to distinguish the content of the rare earth elements in less than 1 cg g-1. The accuracy of the method was assessed by spiked and recovery test (96-104% for spikes equal to or greater than 0.50 cg g-1) and also by the use of different analytical methods, involving the participation of other laboratories, obtaining an acceptable degree of agreement (85 – 107%).","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45803258","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 : 2022-05-04DOI: 10.30744/brjac.2179-3425.ar-112-2021
Khalil Ahmad, Habib-ur-Rehman Shah, Muhammad Ahmad, Muhammad Ahmed, K. Naseem, Nagina Riaz, Ali Muhammad, A. Ayub, M. Ahmad, Z. Ahmad, Alisha Munwar, Abdul Rauf, Riaz Hussain, Muhammad Ashfaq
Water-stable zeolitic imidazolate frameworks (ZIF) with zinc and cobalt cations were synthesized to explore the effect of metal ions on arsenic adsorption. At room temperature (25 2 ºC) and pH 7.8, maximum adsorption capacities of arsenic (As5+) on the surface of ZIF-8 and ZIF-67 were 87.03 and 86.70 mg g-1 respectively, with encouraging results up to 95% reusability of the adsorbents. The results of this study revealed that electrostatic attraction and ion exchange were the major mechanisms responsible for better efficiencies for adsorptive removal of arsenic. The evidence for the adsorption of arsenic contaminants was confirmed by FTIR analyses. The pseudo second order and Langmuir models were best suited to explain the adsorption of arsenic species on the surface of the as-synthesized metal-organic frameworks (MOFs). Based on the results, it was possible to conclude that the metal atoms in the synthesized MOFs had a minor impact on adsorption, since these MOFs presented identical results in the removal of arsenic species. This observation can be explained by the presence of a similar organic linker (2-methyl imidazole), which points to almost the same geometry and sponginess. However, there was a slight difference in the adamsite (organo-arsenic) removal achieved by the MOFs with different metal atoms.
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