Pub Date : 2022-11-11DOI: 10.30744/brjac.2179-3425.ar-59-2022
Vânia Teles, P. Vendramini, R. Augusti, L. Costa
Basil samples (Ocimum basilicum Lameaceae) were exposed to cadmium and analyzed on porous PTFE membrane, and TLC plate substrates by desorption electrospray ionization mass spectrometry imaging (DESI-MSI) for amino acids and sugars identification. The TLC plate was the best substrate for analysis of the basil leaves, with high-definition images, small extract scattering, low mass deviations, and excellent reliability in the spatial distribution of the analytes. DESI-MSI analysis identified 13 images of ions putatively annotated as amino acids and sugars with high accuracy (mass deviation between -1.97 to 1.42 ppm) in contaminated and non-contaminated leaves. In general, the amino acids and sugars (proline, histidine, glutamine, arginine, homoarginine, theanine, hexose sugars, and disaccharides) accumulated preferably in basil leaves as a defense mechanism against exposure to cadmium. Asparagine, tyrosine, glutamic acid, and phenylalanine were inhibited when exposed to the toxic element. The images obtained in this study demonstrated the spatial distribution and accumulation of amino acids and sugars in basil leaves as a response to cadmium contamination, confirming that DESI-MSI is a valuable and promising tool for metabolomics studies in plants exposed to toxic metals.
{"title":"Application of Mass Spectrometry Imaging in Evaluating the Spatial Distribution of Aminoacids and Sugars in Basil Leaves upon Long-Time Exposure to Cadmium","authors":"Vânia Teles, P. Vendramini, R. Augusti, L. Costa","doi":"10.30744/brjac.2179-3425.ar-59-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-59-2022","url":null,"abstract":"Basil samples (Ocimum basilicum Lameaceae) were exposed to cadmium and analyzed on porous PTFE membrane, and TLC plate substrates by desorption electrospray ionization mass spectrometry imaging (DESI-MSI) for amino acids and sugars identification. The TLC plate was the best substrate for analysis of the basil leaves, with high-definition images, small extract scattering, low mass deviations, and excellent reliability in the spatial distribution of the analytes. DESI-MSI analysis identified 13 images of ions putatively annotated as amino acids and sugars with high accuracy (mass deviation between -1.97 to 1.42 ppm) in contaminated and non-contaminated leaves. In general, the amino acids and sugars (proline, histidine, glutamine, arginine, homoarginine, theanine, hexose sugars, and disaccharides) accumulated preferably in basil leaves as a defense mechanism against exposure to cadmium. Asparagine, tyrosine, glutamic acid, and phenylalanine were inhibited when exposed to the toxic element. The images obtained in this study demonstrated the spatial distribution and accumulation of amino acids and sugars in basil leaves as a response to cadmium contamination, confirming that DESI-MSI is a valuable and promising tool for metabolomics studies in plants exposed to toxic metals.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45070376","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 : 2022-10-26DOI: 10.30744/brjac.2179-3425.ar-55-2022
C. Pereira, V. Neves, Graciela Hidrich, H. Faccin, D. Pozebon, V. Dressler
Rice is a food consumed worldwide and there is a grown concern about its nutritional value, as well as the concentration of contaminant elements. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was employed in the present work for determination and imaging of Mg, Mn, Cu, Co, Fe, Zn, As, Sr, Sb, Ba and Pb in grains of white, parboiled, and whole (brown) rice. The elements quantification was achieved by using external calibration whereas filter paper discs served as support for the reference solutions and matrix matching. Accuracy was ensured by analysing two certified reference materials (CRMs) pressed into pellets. Investigations were carried out to evaluate the distribution of the elements on the surface and external layers of the grains. For that purpose, the surface of rice grains fixed on a glass support was ablated line-by-line and the ablation repeated three times. The images generated from laser ablation revealed that the investigated elements were not homogeneously distributed in the analysed parts of the grains. Except for Pb, the investigated elements were detected in three layers of the rice grains, but it was observed that the elements concentrations decreased from the surface to more internal layers. Lead was detected only in the first layer of white and whole rice and in the first and second layers of parboiled rice.
{"title":"Imaging of Elements Distribution in Rice by Laser Ablation Inductively Coupled Plasma Mass Spectrometry","authors":"C. Pereira, V. Neves, Graciela Hidrich, H. Faccin, D. Pozebon, V. Dressler","doi":"10.30744/brjac.2179-3425.ar-55-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-55-2022","url":null,"abstract":"Rice is a food consumed worldwide and there is a grown concern about its nutritional value, as well as the concentration of contaminant elements. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was employed in the present work for determination and imaging of Mg, Mn, Cu, Co, Fe, Zn, As, Sr, Sb, Ba and Pb in grains of white, parboiled, and whole (brown) rice. The elements quantification was achieved by using external calibration whereas filter paper discs served as support for the reference solutions and matrix matching. Accuracy was ensured by analysing two certified reference materials (CRMs) pressed into pellets. Investigations were carried out to evaluate the distribution of the elements on the surface and external layers of the grains. For that purpose, the surface of rice grains fixed on a glass support was ablated line-by-line and the ablation repeated three times. The images generated from laser ablation revealed that the investigated elements were not homogeneously distributed in the analysed parts of the grains. Except for Pb, the investigated elements were detected in three layers of the rice grains, but it was observed that the elements concentrations decreased from the surface to more internal layers. Lead was detected only in the first layer of white and whole rice and in the first and second layers of parboiled rice.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45294032","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 : 2022-10-13DOI: 10.30744/brjac.2179-3425.ar-43-2022
M. Fernandes, A. Camelo, P. Vendramini, M. Brocchi, Ana Simionato
The inappropriate and excessive use of antibiotics for the treatment of bacterial infections has led to the increasing presence of resistant and multidrug-resistant bacteria both in hospital settings and in the community. Thus, understanding the metabolism of resistant bacteria is extremely important to combat them more efficiently. In this scenario, mass spectrometry imaging (MSI) is considered a promising technique for understanding the resistant characteristics of such bacteria and how they can potentially be treated. This process consists of the identification of different ions on the surface of the colonies and the identification of potential metabolites that characterize antibiotic resistance, upon comparison with susceptible bacteria of the same species. This work presents matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) study of colonies of Methicillin-resistant Staphylococcus aureus, as a proof of concept of the technique for obtaining images of bacteria colonies. Images of methicillin-resistant and susceptible colonies of Staphylococcus aureus were obtained by a sublimation process to apply the MALDI matrix on the samples followed by MALDI-MSI analysis. Seventeen (17) potential metabolites were identified and spatially localized, such as N,N-dihydroxy-L-valine, 2-(4-Methylphenyl)ethylamine, 3,4-Dihydroxy-L-phenylalanine, 2-Methyl-hexanoic acid, threonine, Arginine, Aureusimine and Glycyl-D-asparagine. Thus, this study reinforces the potential of MALDI-MSI for identification of metabolites synthesized by different strains of Staphylococcus aureus bacteria.
{"title":"Exploring Bacterial Resistant Metabolism by Matrix-Assisted Laser Desorption Ionization-Mass Spectrometry Imaging","authors":"M. Fernandes, A. Camelo, P. Vendramini, M. Brocchi, Ana Simionato","doi":"10.30744/brjac.2179-3425.ar-43-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-43-2022","url":null,"abstract":"The inappropriate and excessive use of antibiotics for the treatment of bacterial infections has led to the increasing presence of resistant and multidrug-resistant bacteria both in hospital settings and in the community. Thus, understanding the metabolism of resistant bacteria is extremely important to combat them more efficiently. In this scenario, mass spectrometry imaging (MSI) is considered a promising technique for understanding the resistant characteristics of such bacteria and how they can potentially be treated. This process consists of the identification of different ions on the surface of the colonies and the identification of potential metabolites that characterize antibiotic resistance, upon comparison with susceptible bacteria of the same species. This work presents matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) study of colonies of Methicillin-resistant Staphylococcus aureus, as a proof of concept of the technique for obtaining images of bacteria colonies. Images of methicillin-resistant and susceptible colonies of Staphylococcus aureus were obtained by a sublimation process to apply the MALDI matrix on the samples followed by MALDI-MSI analysis. Seventeen (17) potential metabolites were identified and spatially localized, such as N,N-dihydroxy-L-valine, 2-(4-Methylphenyl)ethylamine, 3,4-Dihydroxy-L-phenylalanine, 2-Methyl-hexanoic acid, threonine, Arginine, Aureusimine and Glycyl-D-asparagine. Thus, this study reinforces the potential of MALDI-MSI for identification of metabolites synthesized by different strains of Staphylococcus aureus bacteria.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44041954","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 : 2022-10-06DOI: 10.30744/brjac.2179-3425.ar-46-2022
Fabiana dos Santos, F. Monedeiro, Jesus Velho, Sergio de Souza, E. D. de Campos, B. D. de Martinis
Cocaine is an illicit drug commonly found by law enforcement in seizures around the world. This paper describes a rare case of cocaine trafficking in asphaltic material, possibly in the form of cocaine hydrochloride. The material was found and seized in barrels during an operation conducted by the Brazilian Federal Police. The sample was initially extracted and resulted negative for cocaine via Scott’s Test, but further screening by gas chromatography coupled with mass spectrometry (GC-MS) confirmed the presence of cocaine. Afterwards, samples were subjected to quantitative GC-MS analysis. The concentrations of cocaine ranged from 0.11 to 1.53 ng/10 mg in the extracts of precipitate material found in the barrels. Considering that extraction efficiency was around 57.44%, it is estimated that 1.07 – 15.34% of barrel’s sediment weight was constituted by cocaine.
{"title":"Cocaine Trafficking in Asphalt Material: An Unusual Report of Cocaine in Seized Drugs","authors":"Fabiana dos Santos, F. Monedeiro, Jesus Velho, Sergio de Souza, E. D. de Campos, B. D. de Martinis","doi":"10.30744/brjac.2179-3425.ar-46-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-46-2022","url":null,"abstract":"Cocaine is an illicit drug commonly found by law enforcement in seizures around the world. This paper describes a rare case of cocaine trafficking in asphaltic material, possibly in the form of cocaine hydrochloride. The material was found and seized in barrels during an operation conducted by the Brazilian Federal Police. The sample was initially extracted and resulted negative for cocaine via Scott’s Test, but further screening by gas chromatography coupled with mass spectrometry (GC-MS) confirmed the presence of cocaine. Afterwards, samples were subjected to quantitative GC-MS analysis. The concentrations of cocaine ranged from 0.11 to 1.53 ng/10 mg in the extracts of precipitate material found in the barrels. Considering that extraction efficiency was around 57.44%, it is estimated that 1.07 – 15.34% of barrel’s sediment weight was constituted by cocaine.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47835484","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 : 2022-10-06DOI: 10.30744/brjac.2179-3425.rv-60-2022
C. D. de Paula
In this review, the use of mass spectrometry imaging (MSI) was addressed, focusing on the study of plant tissues, especially vegetables. The discussion about the taxonomy of plant tissues and organs is commonly based on immunohistochemistry and immunofluorescence essays. Although these techniques are quite appropriate for the structural study of tissues and organs, their low specificity limits their use to the identification of only a few compounds. Mass spectrometry (MS) hyphenated with chromatography techniques are capable to identifying a wide variety of compounds in plant tissue matrices, but these analyzes do not provide spatial information of the sample. MSI techniques stands out in this scenario due their capacity to provide information about both composition and spatial distribution of different biological matrices in the in the same approach. The potential of the MSI techniques to provide information about primary and secondary metabolites in plant tissue, as well as chemical responses associated with external stimuli, can be demonstrated through published works that employ different ionization sources such as SIMS, MALDI and DESI and their modifications.
{"title":"Mass Spectrometry Imaging for Vegetables: A Review","authors":"C. D. de Paula","doi":"10.30744/brjac.2179-3425.rv-60-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.rv-60-2022","url":null,"abstract":"In this review, the use of mass spectrometry imaging (MSI) was addressed, focusing on the study of plant tissues, especially vegetables. The discussion about the taxonomy of plant tissues and organs is commonly based on immunohistochemistry and immunofluorescence essays. Although these techniques are quite appropriate for the structural study of tissues and organs, their low specificity limits their use to the identification of only a few compounds. Mass spectrometry (MS) hyphenated with chromatography techniques are capable to identifying a wide variety of compounds in plant tissue matrices, but these analyzes do not provide spatial information of the sample. MSI techniques stands out in this scenario due their capacity to provide information about both composition and spatial distribution of different biological matrices in the in the same approach. The potential of the MSI techniques to provide information about primary and secondary metabolites in plant tissue, as well as chemical responses associated with external stimuli, can be demonstrated through published works that employ different ionization sources such as SIMS, MALDI and DESI and their modifications.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47840506","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 : 2022-10-05DOI: 10.30744/brjac.2179-3425.interview.srath
S. Rath
Susanne Rath is an associate professor in the Institute of Chemistry at the University of Campinas (Unicamp), where she coordinates the “Laboratório de Bioanalítica Paracelsus”. She graduated with a Bachelor's degree in Chemistry (1983) from the University of Brasília (UnB), a Master’s degree in Chemistry (1986) from Unicamp, and a Ph.D in Pharmaceutical Chemistry (1990) from the Johann Wolfgang Goethe Universität Frankfurt am Main, Germany. So far, she has published 110 articles and seven book chapters, had four patents granted, and she has presented over 230 papers at scientific conferences. She supervised 17 master's students, 20 doctorate students and 10 post-docs. In addition, she coordinated 23 research projects supported by Brazilian funding agencies. Prof. Dr. Rath’s primary research is focused on toxic compounds in food, residue depletion studies of veterinary drugs in food-producing animals, development and validation of analytical methods, application of bidimensional chromatography and mass spectrometry, environmental impact assessment of veterinary drugs, antimicrobial resistance and N-nitrosamines in food, cosmetics and drugs. Since 2007, Prof. Rath has been a member of the Joint Expert Committee on Food Additives (JECFA) of the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO). Since 2011, Prof. Rath has been a member of the Technical Group on Maximum Residue Limits for Veterinary Drugs in Food of the National Health Surveillance Agency (Anvisa) of the Ministry of Health of Brazil.
Susanne Rath是坎皮纳斯大学(Unicamp)化学研究所的副教授，负责协调“Laboratório de Bioanalítica Paracelsus”项目。她毕业于University of Brasília (UnB)的化学学士学位(1983年)，Unicamp的化学硕士学位(1986年)，以及德国法兰克福的Johann Wolfgang Goethe Universität的药物化学博士学位(1990年)。到目前为止，她已经发表了110篇文章和7本书章节，获得了4项专利，并在科学会议上发表了230多篇论文。硕士生17人，博士生20人，博士后10人。此外，她还协调了23个由巴西资助机构支持的研究项目。Rath教授的主要研究领域包括食品中的有毒化合物、兽药在食用动物体内的残留去除研究、分析方法的开发和验证、二维色谱和质谱的应用、兽药的环境影响评估、抗微生物药物耐药性和食品、化妆品和药物中的n -亚硝胺。自2007年以来，Rath教授一直是联合国粮食及农业组织(粮农组织)和世界卫生组织(世卫组织)食品添加剂联合专家委员会(JECFA)的成员。自2011年以来，Rath教授一直是巴西卫生部国家卫生监督局(Anvisa)食品中兽药最大残留限量技术小组的成员。
{"title":"Professor Susanne Rath, a researcher who has bravely faced challenges since childhood, kindly granted BrJAC an interview","authors":"S. Rath","doi":"10.30744/brjac.2179-3425.interview.srath","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.interview.srath","url":null,"abstract":"Susanne Rath is an associate professor in the Institute of Chemistry at the University of Campinas (Unicamp), where she coordinates the “Laboratório de Bioanalítica Paracelsus”. She graduated with a Bachelor's degree in Chemistry (1983) from the University of Brasília (UnB), a Master’s degree in Chemistry (1986) from Unicamp, and a Ph.D in Pharmaceutical Chemistry (1990) from the Johann Wolfgang Goethe Universität Frankfurt am Main, Germany. So far, she has published 110 articles and seven book chapters, had four patents granted, and she has presented over 230 papers at scientific conferences. She supervised 17 master's students, 20 doctorate students and 10 post-docs. In addition, she coordinated 23 research projects supported by Brazilian funding agencies. Prof. Dr. Rath’s primary research is focused on toxic compounds in food, residue depletion studies of veterinary drugs in food-producing animals, development and validation of analytical methods, application of bidimensional chromatography and mass spectrometry, environmental impact assessment of veterinary drugs, antimicrobial resistance and N-nitrosamines in food, cosmetics and drugs. Since 2007, Prof. Rath has been a member of the Joint Expert Committee on Food Additives (JECFA) of the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO). Since 2011, Prof. Rath has been a member of the Technical Group on Maximum Residue Limits for Veterinary Drugs in Food of the National Health Surveillance Agency (Anvisa) of the Ministry of Health of Brazil.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44148232","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 : 2022-10-05DOI: 10.30744/brjac.2179-3425.point-of-view-wktcoltro.n37
W. Coltro
In the last three decades, the scientific community has observed exponential growth in the development of microfluidic platforms and their use for applications in different fields. The noticeable advances are attributed to the advantages provided by miniaturization.1 In summary, the downscaling of analytical devices has offered attractive features, including reduced consumption of samples and reagents, short analysis time, and minimal waste generation. In addition, the possibility to perform multiplexed assays in portable devices without bulky instrumentation is another attractive feature that boosted the investigation of miniaturized devices with the capability to be tested directly in the point-of-care (POC). Due to the sample volume required to proceed with a chemical analysis on a microscale (typically in the µL range), a complete understanding of the fluid control and handle on channels defined in micrometric dimensions was necessary, giving rise to the science known as microfluidics.2 Many platforms including rigid and flexible materials can be explored for manufacturing microfluidic networks. Among all the substrates reported in the literature, the “paper” is by far the simplest and cheapest material currently employed for the development of microfluidic devices dedicated to analytical, bioanalytical, biomedical, environmental, food, and forensics applications.3 For many readers, the first question is why paper is used instead of other materials such as glass. Well, glass is a rigid material, and microchannel engraving requires cleanroom facilities, photolithographic patterning, developing steps, and thermal sealing. This standard protocol makes use of sophisticated instrumentation, and it is not readily available to most researchers. In this way, paper emerges as a simple and alternative material to be used for microfluidics. One of the major benefits of microfluidics refers to the sample-in-answer-out capability, which requires a fully automated fluid control to allow sample preparation, analytical separation, and detection stages. The fluid-controlled handling inside microchannels opens the possibility to integrate multiple analytical tasks in parallel into a high-throughput device. Considering these possibilities, it is worthwhile reflecting on how paper can be used to transport and handle a fluid. Paper is currently one of the most widely used raw materials in research laboratories. Its use has been explored for over a century. In 1949, a paper containing barriers made of paraffin was exploited to successfully demonstrate the elution of pigments within a channel based on the sample diffusion process.4 In 2007, paper was reinvented by the Whitesides group as a globally affordable substrate material for the development of miniaturized analytical platforms.5 Since this period, paper has become an increasingly popular platform for multipurpose applications. Probably, its broad use is associated with advantages over other conventional subs
{"title":"Paper-based microfluidics: What can we expect?","authors":"W. Coltro","doi":"10.30744/brjac.2179-3425.point-of-view-wktcoltro.n37","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.point-of-view-wktcoltro.n37","url":null,"abstract":"In the last three decades, the scientific community has observed exponential growth in the development of microfluidic platforms and their use for applications in different fields. The noticeable advances are attributed to the advantages provided by miniaturization.1 In summary, the downscaling of analytical devices has offered attractive features, including reduced consumption of samples and reagents, short analysis time, and minimal waste generation. In addition, the possibility to perform multiplexed assays in portable devices without bulky instrumentation is another attractive feature that boosted the investigation of miniaturized devices with the capability to be tested directly in the point-of-care (POC). Due to the sample volume required to proceed with a chemical analysis on a microscale (typically in the µL range), a complete understanding of the fluid control and handle on channels defined in micrometric dimensions was necessary, giving rise to the science known as microfluidics.2 Many platforms including rigid and flexible materials can be explored for manufacturing microfluidic networks. Among all the substrates reported in the literature, the “paper” is by far the simplest and cheapest material currently employed for the development of microfluidic devices dedicated to analytical, bioanalytical, biomedical, environmental, food, and forensics applications.3 For many readers, the first question is why paper is used instead of other materials such as glass. Well, glass is a rigid material, and microchannel engraving requires cleanroom facilities, photolithographic patterning, developing steps, and thermal sealing. This standard protocol makes use of sophisticated instrumentation, and it is not readily available to most researchers. In this way, paper emerges as a simple and alternative material to be used for microfluidics. One of the major benefits of microfluidics refers to the sample-in-answer-out capability, which requires a fully automated fluid control to allow sample preparation, analytical separation, and detection stages. The fluid-controlled handling inside microchannels opens the possibility to integrate multiple analytical tasks in parallel into a high-throughput device. Considering these possibilities, it is worthwhile reflecting on how paper can be used to transport and handle a fluid. Paper is currently one of the most widely used raw materials in research laboratories. Its use has been explored for over a century. In 1949, a paper containing barriers made of paraffin was exploited to successfully demonstrate the elution of pigments within a channel based on the sample diffusion process.4 In 2007, paper was reinvented by the Whitesides group as a globally affordable substrate material for the development of miniaturized analytical platforms.5 Since this period, paper has become an increasingly popular platform for multipurpose applications. Probably, its broad use is associated with advantages over other conventional subs","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49113364","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 : 2022-10-05DOI: 10.30744/brjac.2179-3425.inmemoriam.carol-collins
C. Bottoli
Professor Carol Collins graduated in Chemistry from Bates College (1952) and obtained her PhD in Organic Physical Chemistry from Iowa State University of Science and Technology (1958), when she was introduced to the recently developed gas–liquid chromatography. She conducted postdoctoral research at the University of Wisconsin and later worked on radiochemistry and nuclear medicine at the Brookhaven National Laboratory and the Western New York Nuclear Research Center in Louvain (Belgium) and Southwest Asia. Professor Collins came to the State University of Campinas (Unicamp) with her husband, Kenneth Collins, in July 1974, during the university’s first decade, and played a leading role in consolidation of the Institute of Chemistry at Unicamp and in the growth of chemistry and analytical chemistry in Brazil. Her first line of research in Brazil was radioanalytical chemistry, later focusing on chromatographic techniques, initially applied to the products of radiochemical reactions and radiation chemistry. Subsequently, her attention was directed to the preparation of stationary phases for liquid chromatography. She gained remarkable achievement in the area of chromatography that allowed her to publish two books that are very popular in Brazil: "Introduction to Chromatographic Methods" (1987) and "Fundamentals of Chromatography" (2006). Her scientific and technological contributions have been recognized through several awards, including the “Marie Curie Award” from the American Association of University Women and the “Simão Mathias Medal” from the Brazilian Chemical Society (SBQ). She also received honors in recognition of the contributions of Unicamp's 40th anniversary, SBQ's 30th anniversary, a tribute from the Journal of the Brazilian Chemical Society, the National Meeting of Analytical Chemistry, the School of Separations and the Brazilian Symposium on Chromatography and Related Techniques (SIMCRO) Medal. For her outstanding performance and leadership in the creation and consolidation of the Analytical Chemistry Division of the Brazilian Chemical Society, her name was recognized in the Carol Collins Medal given to each National Meeting of Analytical Chemistry since the 2018 edition. Professor Collins was also a full member of the Brazilian Academy of Sciences and the Academy of Sciences of São Paulo, and received the title of Professor Emerita of Unicamp on 14 May 2012, in addition to being Emeritus Researcher at the National Council for Scientific and Technological Development (CNPq). Apart from her scientific competence, some characteristics shaped her personality and made her very popular among her colleagues and students: her vast gourmet knowledge, keen taste for caipirinha and coffee, infallible memory, great love for her work and for Brazil, dedication to science, analytical chemistry/chromatography, kindness as a person and her incessant search for justice. She was always receptive to clarifying the doubts of students, teachers and inte
Carol Collins教授1952年毕业于贝茨学院化学专业，1958年在爱荷华州立科技大学获得有机物理化学博士学位，当时她接触了最近发展起来的气液色谱法。她在威斯康星大学进行博士后研究，后来在布鲁克海文国家实验室和位于比利时鲁汶和西南亚的西纽约核研究中心从事放射化学和核医学工作。1974年7月，在坎皮纳斯州立大学(Unicamp)成立的第一个十年期间，柯林斯教授与丈夫肯尼斯·柯林斯(Kenneth Collins)来到坎皮纳斯州立大学(Unicamp)，并在坎皮纳斯州立大学化学研究所的整合以及巴西化学和分析化学的发展中发挥了主导作用。她在巴西的第一个研究方向是放射分析化学，后来专注于色谱技术，最初应用于放射化学反应和辐射化学的产物。随后，她的注意力转向了液相色谱固定相的制备。她在色谱学领域取得了显著成就，出版了两本在巴西非常受欢迎的书:《色谱方法入门》(1987年)和《色谱学基础》(2006年)。她的科学和技术贡献获得了多个奖项的认可，包括美国大学妇女协会的“玛丽居里奖”和巴西化学学会(SBQ)的“sim o Mathias奖章”。她还获得了Unicamp成立40周年、SBQ成立30周年、巴西化学学会杂志、全国分析化学会议、分离学院和巴西色谱及相关技术研讨会(SIMCRO)奖章等荣誉。由于她在巴西化学会分析化学部门的创建和巩固方面的杰出表现和领导作用，自2018年以来，她的名字被授予每个国家分析化学会议的卡罗尔·柯林斯奖章。Collins教授还是巴西科学院和圣保罗科学院的正式成员，并于2012年5月14日获得Unicamp的荣誉教授头衔，此外他还是国家科学和技术发展委员会(CNPq)的荣誉研究员。除了她的科学能力之外，她的一些特点塑造了她的个性，并使她在同事和学生中非常受欢迎:她丰富的美食知识，对凯皮林纳酒和咖啡的敏锐品味，准确的记忆力，对她的工作和巴西的热爱，对科学的奉献，分析化学/色谱，为人善良，以及对正义的不断追求。她总是乐于澄清学生、老师和有关各方的疑问，她做得非常愉快，这是一个喜欢教授和传播知识的人的特点。柯林斯教授对人力资源培训、Unicamp化学研究所的巩固和发展以及巴西和国外分析化学/色谱部门的贡献是不可估量的。她辉煌的人生轨迹将留下难以估量的巨大遗产，她将永远留在那些有幸与她生活在一起的人的记忆中。
{"title":"In Memoriam - BrJAC mourns the death of Prof. Dr. Carol Hollingworth Collins and recognizes her great contribution to the Analytical Chemistry in Brazil","authors":"C. Bottoli","doi":"10.30744/brjac.2179-3425.inmemoriam.carol-collins","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.inmemoriam.carol-collins","url":null,"abstract":"Professor Carol Collins graduated in Chemistry from Bates College (1952) and obtained her PhD in Organic Physical Chemistry from Iowa State University of Science and Technology (1958), when she was introduced to the recently developed gas–liquid chromatography. She conducted postdoctoral research at the University of Wisconsin and later worked on radiochemistry and nuclear medicine at the Brookhaven National Laboratory and the Western New York Nuclear Research Center in Louvain (Belgium) and Southwest Asia. Professor Collins came to the State University of Campinas (Unicamp) with her husband, Kenneth Collins, in July 1974, during the university’s first decade, and played a leading role in consolidation of the Institute of Chemistry at Unicamp and in the growth of chemistry and analytical chemistry in Brazil. Her first line of research in Brazil was radioanalytical chemistry, later focusing on chromatographic techniques, initially applied to the products of radiochemical reactions and radiation chemistry. Subsequently, her attention was directed to the preparation of stationary phases for liquid chromatography. She gained remarkable achievement in the area of chromatography that allowed her to publish two books that are very popular in Brazil: \"Introduction to Chromatographic Methods\" (1987) and \"Fundamentals of Chromatography\" (2006). Her scientific and technological contributions have been recognized through several awards, including the “Marie Curie Award” from the American Association of University Women and the “Simão Mathias Medal” from the Brazilian Chemical Society (SBQ). She also received honors in recognition of the contributions of Unicamp's 40th anniversary, SBQ's 30th anniversary, a tribute from the Journal of the Brazilian Chemical Society, the National Meeting of Analytical Chemistry, the School of Separations and the Brazilian Symposium on Chromatography and Related Techniques (SIMCRO) Medal. For her outstanding performance and leadership in the creation and consolidation of the Analytical Chemistry Division of the Brazilian Chemical Society, her name was recognized in the Carol Collins Medal given to each National Meeting of Analytical Chemistry since the 2018 edition. Professor Collins was also a full member of the Brazilian Academy of Sciences and the Academy of Sciences of São Paulo, and received the title of Professor Emerita of Unicamp on 14 May 2012, in addition to being Emeritus Researcher at the National Council for Scientific and Technological Development (CNPq). Apart from her scientific competence, some characteristics shaped her personality and made her very popular among her colleagues and students: her vast gourmet knowledge, keen taste for caipirinha and coffee, infallible memory, great love for her work and for Brazil, dedication to science, analytical chemistry/chromatography, kindness as a person and her incessant search for justice. She was always receptive to clarifying the doubts of students, teachers and inte","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48791165","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 : 2022-10-05DOI: 10.30744/brjac.2179-3425.letter-fabiolaverbi.n37
F. Pereira
The application of chemometric tools in analytical chemistry or other areas of chemistry has become essential. This is mainly due to the large amount and nature of the generated data1,2 and the need to extract useful information from these and optimize steps throughout a process. It allows the quick decision-making visualization of interactions among variables, such as synergism or antagonism between parameters, during the development of a method,3 as shown in Figure 1. Classical chemometric techniques have been disseminated and can be divided according to the study approach, among which exploratory data analysis stands out. Principal component analysis (PCA) is one of the most accessible and well-established ways to perform an initial exploration and extract relevant information from a given dataset and has been used quite successfully in various spectroscopic techniques.4 Principal component analysis consists of projecting the data in a smaller dimension, enabling the detection of anomalous samples (outliers), the selection of essential variables in a given system, and unsupervised classification.1,2,4 Another branch of chemometrics involves the design of experiments (DoE). The primary purpose of the factorial design is to study the influence or effect of a given variable and its interactions in a specific system.5-9 Multivariate calibration is another aspect of chemometrics, where several variables are used to calibrate one (or more) property or the concentration of a given chemical analyte.10,11 Since the first publications of chemometric tools, numerous variations of these techniques, proposals for data fusion strategies, and applications using hyphenated instrumental techniques have been proposed.12-14 Industrial quality control and development (R&D) laboratories require an approach addressing adequate quality by design (QbD). The QbD strategies consider four steps that include an analytical target profile (ATP), a risk assessment, a design space (DS), and control strategy and validation based on figures of merit, for instance.9 Principal component analysis is the most widely multivariate technique used for data analysis. Jolliffe wrote a review reporting his wonderful experience with PCA in the last 50 years.15 Indeed, PCA is an invaluable method for data, and I agree with it. PCA is the algorithm of choice for numerous chemometric techniques.16 Other computational languages, such as Python, are currently experiencing a rise in popularity in the field of chemistry. The R language has also become more popular than it was ten years ago. The scripts, functions, or codes are easily written with fewer lines and specific commands that minimize steps and help speed up calculations. The dissemination of free software has also become popular, and the sharing of codes through publications, social media, communities, or websites has become relatively easy. From my point of view, chemometrics is no longer faced as a giant monster or a way to become sc
{"title":"Chemometrics reveals not-so-obvious analytical information","authors":"F. Pereira","doi":"10.30744/brjac.2179-3425.letter-fabiolaverbi.n37","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.letter-fabiolaverbi.n37","url":null,"abstract":"The application of chemometric tools in analytical chemistry or other areas of chemistry has become essential. This is mainly due to the large amount and nature of the generated data1,2 and the need to extract useful information from these and optimize steps throughout a process. It allows the quick decision-making visualization of interactions among variables, such as synergism or antagonism between parameters, during the development of a method,3 as shown in Figure 1. Classical chemometric techniques have been disseminated and can be divided according to the study approach, among which exploratory data analysis stands out. Principal component analysis (PCA) is one of the most accessible and well-established ways to perform an initial exploration and extract relevant information from a given dataset and has been used quite successfully in various spectroscopic techniques.4 Principal component analysis consists of projecting the data in a smaller dimension, enabling the detection of anomalous samples (outliers), the selection of essential variables in a given system, and unsupervised classification.1,2,4 Another branch of chemometrics involves the design of experiments (DoE). The primary purpose of the factorial design is to study the influence or effect of a given variable and its interactions in a specific system.5-9 Multivariate calibration is another aspect of chemometrics, where several variables are used to calibrate one (or more) property or the concentration of a given chemical analyte.10,11 Since the first publications of chemometric tools, numerous variations of these techniques, proposals for data fusion strategies, and applications using hyphenated instrumental techniques have been proposed.12-14 Industrial quality control and development (R&D) laboratories require an approach addressing adequate quality by design (QbD). The QbD strategies consider four steps that include an analytical target profile (ATP), a risk assessment, a design space (DS), and control strategy and validation based on figures of merit, for instance.9 Principal component analysis is the most widely multivariate technique used for data analysis. Jolliffe wrote a review reporting his wonderful experience with PCA in the last 50 years.15 Indeed, PCA is an invaluable method for data, and I agree with it. PCA is the algorithm of choice for numerous chemometric techniques.16 Other computational languages, such as Python, are currently experiencing a rise in popularity in the field of chemistry. The R language has also become more popular than it was ten years ago. The scripts, functions, or codes are easily written with fewer lines and specific commands that minimize steps and help speed up calculations. The dissemination of free software has also become popular, and the sharing of codes through publications, social media, communities, or websites has become relatively easy. From my point of view, chemometrics is no longer faced as a giant monster or a way to become sc","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46525004","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 : 2022-09-26DOI: 10.30744/brjac.2179-3425.ar-50-2022
khadeejah alyasiri, F. Al-Zubaidi, Layla Mohammed
A new, sensitive, and accurate spectrophotometric method for determining lead (II) ion in vegetables samples, using laboratory prepared reagent (6-MBTAMP) is developed. The reagent and pb+2 complex characterization included infrared spectroscopy, ultraviolet-visible spectrophotometry, elemental analysis (CHN), energy dispersive X-ray spectroscopy (EDX), and nuclear magnetic resonance spectroscopy (1HNMR & 13CNMR) techniques. The method depends on the reaction of lead (II) with the 6-MBTAMP reagent in a neutral medium to form a green-red complex which showed a maximum absorbance at 670 nm. The optimum conditions such as pH of the medium, reagent volume, reagent concentration, and time effect were also investigated carefully. Limit of detection (LOD), limit of quantification (LOQ) and Sandell’s sensitivity were calculated to be 0.181 mg L-1, 0.604 mg L-1 and 0.03 µg cm-2 respectively. The proposed method obeyed Beer’s law at range of 0.6-10 mg L-1 and the recovery percentage of the vegetable samples ranged from 71% to 106.6%. The suggested spectrophotometric technique is proved to be simple, fast and sensitive for determination of Pb (II) ion in vegetables samples.
{"title":"A New Spectrophotometric Method to Determinate Lead (II) Ion in Vegetables with 2-[(6-Methoxy-2-benzothiazolyl) azo]-4-methoxy phenol as a New Reagent","authors":"khadeejah alyasiri, F. Al-Zubaidi, Layla Mohammed","doi":"10.30744/brjac.2179-3425.ar-50-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-50-2022","url":null,"abstract":"A new, sensitive, and accurate spectrophotometric method for determining lead (II) ion in vegetables samples, using laboratory prepared reagent (6-MBTAMP) is developed. The reagent and pb+2 complex characterization included infrared spectroscopy, ultraviolet-visible spectrophotometry, elemental analysis (CHN), energy dispersive X-ray spectroscopy (EDX), and nuclear magnetic resonance spectroscopy (1HNMR & 13CNMR) techniques. The method depends on the reaction of lead (II) with the 6-MBTAMP reagent in a neutral medium to form a green-red complex which showed a maximum absorbance at 670 nm. The optimum conditions such as pH of the medium, reagent volume, reagent concentration, and time effect were also investigated carefully. Limit of detection (LOD), limit of quantification (LOQ) and Sandell’s sensitivity were calculated to be 0.181 mg L-1, 0.604 mg L-1 and 0.03 µg cm-2 respectively. The proposed method obeyed Beer’s law at range of 0.6-10 mg L-1 and the recovery percentage of the vegetable samples ranged from 71% to 106.6%. The suggested spectrophotometric technique is proved to be simple, fast and sensitive for determination of Pb (II) ion in vegetables samples.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42759317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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