Brazilian Journal of Analytical Chemistry最新文献

{"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":" ","pages":""},"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}

{"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":" ","pages":""},"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}

{"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":" ","pages":""},"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}

{"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":" ","pages":""},"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}

{"title":"Evaluation of a Lignin Bio-alkyd Resin for the Selective Determination of Molybdenum in Biological, Pharmaceutical, Fertilizer and Water Samples","authors":"E. Moawed, Sara Ragab, A. El-Shobaky, Maha El Hagrasy","doi":"10.30744/brjac.2179-3425.ar-122-2021","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-122-2021","url":null,"abstract":"A lignin-based bio-alkyd resin (LA-Resin) was synthesized by the polycondensation reaction of lignin with a mixture of palmitic acid and glycerol. The LA-Resin was characterized using many techniques, including scanning electron microscope, FTIR, X-ray diffraction and thermal analysis. LA-Resin was proven to have graphitized structures with enhanced surface functional groups, showing a slightly basic character (pHZCP = 7.8). It has a relatively better cation exchange capacity (0.70 mmol g-1) in addition to the ability for physical adsorption. The performance of LA-Resin was assessed for the uptake of molybdenum (Mo), followed by spectrophotometric determination, applying both batch and column techniques. Elevated sorption percentages of Mo were observed in acidic medium H2SO4 (1.5 mol L-1) in the presence of ascorbic acid (0.050 mol L-1) and NH4SCN (0.10 mol L-1). The method was successfully applied to the separation and determination of Mo in mice liver, pharmaceuticals, water and fertilizer samples. Validation showed good recovery (96.6-99.6%), sensitivity (LOD, 0.9-4.0 μg L-1), repeatability (RSD% ≤1.5%) and linearity (R2 = 0.984), demonstrating a good quantitative performance of the method. Mo in all investigated samples regardless of different matrices were well-separated and detected, indicating that the method is sensitive enough to detect low concentrations of Mo even in small samples such as mice liver.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48656706","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}

{"title":"Comparative Study Between Two Zeolitic Imidazolate Frameworks as Adsorbents for Removal of Organoarsenic, As(III) and As(V) Species from Water","authors":"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","doi":"10.30744/brjac.2179-3425.ar-112-2021","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-112-2021","url":null,"abstract":"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.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41336557","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}

{"title":"Analytical and Bioanalytical Chemistry It is time we innovate","authors":"E. Carrilho","doi":"10.30744/brjac.2179-3425.point-of-view.ecarrilho.n35","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.point-of-view.ecarrilho.n35","url":null,"abstract":"It is time we innovate from the bottom up! From the analytical chemistry curriculum to the approach we take in teaching it. From the problems we are set to solve to the opportunities we create. Innovation and entrepreneurship are two words that are the “hype of the moment”, indeed! But this is for the greater good! Modern societies and highly developed countries invest heavily in education and science and have open economies, with little or no bureaucracy to start a business or create a company. Startups, spin-offs, investors, and profit are words that should be in the minds of young analytical and bioanalytical chemists. Profit, contrary to what our Judaic-Christian religious background has stamped in our subconscious, is not a bad word. It is not a sin!","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48524834","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}

{"title":"About this issue","authors":"L. Hantao","doi":"10.30744/brjac.2179-3425.editorial.lwhantao.n35","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.editorial.lwhantao.n35","url":null,"abstract":"Modern analytical chemistry comprises an amazing scope of techniques and methods used for the characterization of analytes in complex matrices. Despite the numerous formats and instrument configurations, the challenges faced by analysts in innovation-driven environments are, in essence, the same. Recent advances in separation science have imposed new requirements for sampling and sample preparation, which has ultimately altered the essence of contemporary sample preparation. Advances in column technology and multidimensional instrumentation has led to the achievement of unprecedented peak capacities. The evolution of hyphenated methods has enabled the generation of information-dense data tensors, which ultimately impact the fundamental role and formats available for data processing and interpretation (see Issue #32). This paradigm shift has created exciting opportunities for analytical chemistry. In this issue #35, we have carefully selected applications covering some of the most important steps of an analytical method, namely, sample preparation and method development using separation and spectroscopy to solve real world tasks. For instance, a review article covers the potential of combining restricted access materials with molecularly imprinted polymers for bioanalytical applications. This article is followed by a report on the extraction and characterization of Tamarind gum from an unusual source of biomass, which is an important step towards the circular economy. Next, applications of liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) and inductively coupled plasma mass spectrometry (ICP-MS) are also available for the interested reader. In this issue, we have also interviewed Dr. Gisele Tonietto about the dissemination of science, published a point of view with Dr. Emanuel Carrilho, and a letter from Dr. Cesar Tarley. Lastly, I would like to thank all the authors, reviewers, and editorial staff for putting this much effort and dedication into publishing this issue on time. This journal has grown beyond expectations, while accompanying the evolution of research and innovation in Brazil. It is our hope to continue pushing the boundaries of science by inviting interested authors from Latin American and the world. I look forward to publishing manuscripts that will also recognize and promote equality in science, highlighting role models for younger generations of researchers.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46369214","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}

{"title":"Chemical Imprinting Technology Applied to Analytical Chemistry: Current Status and Future Outlook in Brazil","authors":"C. Tarley","doi":"10.30744/brjac.2179-3425.letter.crtarley.n35","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.letter.crtarley.n35","url":null,"abstract":"Chemical imprinting technologies based on molecularly imprinted polymers (MIPs) and ion imprinted polymers (IIPs) have been widely applied in different fields of analytical chemistry since their discoveries in 19721 and 19762, respectively. MIPs and IIPs are considered biomimetic materials with tailor-made synthetic receptors and are, essentially, obtained by co-polymerization of functional and cross-linking monomers in the presence of a target analyte (a molecule for MIPs and an ion for IIPs). The great advantages of these materials over biological recognition systems include their relatively low cost, quick preparation, and, most importantly, their stability in different media. To date, these biomimetic materials have experienced a rapid development with wide applications in electrochemical sensors, luminescence sensors, separation science, sample preparation, and more specific sensor applications such as surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) sensors. In addition, they have been applied for analysis of samples of environmental, food, and forensic interests, as well as for disease diagnostics.3-8 Figure 1 depicts the increasing number of published papers per year over the past 20 years on the topic of MIPs and IIPs; as expected, most of these papers are devoted to the chemical imprinting of molecules.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49288157","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}

{"title":"Gisele Birman Tonietto, a Coordinator of Development Projects and a Dynamic Researcher also Dedicated to the Dissemination of Science, kindly spoke to BrJAC","authors":"G. Tonietto","doi":"10.30744/brjac.2179-3425.interview.gbtonietto","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.interview.gbtonietto","url":null,"abstract":"Prof. Dr. Gisele Birman Tonietto is a professor in the Department of Chemistry at the Pontifical Catholic University of Rio de Janeiro and Coordinator of Development Projects at the Analytical Center of the same university. Prof. Tonietto holds a degree in Industrial Chemistry from the Fluminense Federal University (1989), a master's degree in Chemistry from the Pontifical Catholic University of Rio de Janeiro (1995), and a Ph.D. in Chemistry from the Pontifical Catholic University of Rio de Janeiro (2006). Her research focuses on analytical chemistry, working mainly on ion chromatography, microwaves, arsenic and selenium speciation, and isotopic analysis of carbon, hydrogen and oxygen. Prof. Tonietto is also dedicated to the dissemination of science, developing digital content and promoting interviews, round tables, and training in various areas of chemistry. She received the University Merit Diploma from PUC-Rio in 2021 and is a member of the Technical Chamber of Oil and Gas of the Regional Council of Chemistry of Rio de Janeiro.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41607712","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}