Pub Date : 2023-08-29DOI: 10.30744/brjac.2179-3425.ar-32-2023
Jean Paulo Coll, Michele da Cunha, Maria Alice Amaral, Maurício Padilha, G. da Silva, Daniel Arsand, P. S. Sanches Filho
The objective of this work was to optimize a chromatographic method, combining derivatization (silylation) with MSTFA (N-methyl-N-(trimethylsilyl)trifluoracetamide) and analysis by gas chromatography coupled to mass spectrometry (GC-MS), for the determination of hormones and UV filters selectively, evaluating the effect of derivatization on the chromatographic response. The method developed for the qualitative analysis (SCAN mode) allowed the identification of the analytes more accurately, with similarities of the spectra superior to 80%. The limits of detection and quantification ranged from 0.1 to 1.3 µg L-1 and 0.3 to 4.2 µg L-1 respectively. The quantitative method, combined silylation with chromatographic determination in SIM mode, proved to be precise (Relative standard deviation <7.2%) and exact (relative error <2.0%), with models without lack of fit, and with correlation coefficients linear values greater than 0.9, in accordance with the requirements and standards of the regulatory bodies.
{"title":"Evaluation of the Effect of Silylation in the Development of an Analytical Method for the Determination of UV Filters and Hormones by GC-MS","authors":"Jean Paulo Coll, Michele da Cunha, Maria Alice Amaral, Maurício Padilha, G. da Silva, Daniel Arsand, P. S. Sanches Filho","doi":"10.30744/brjac.2179-3425.ar-32-2023","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-32-2023","url":null,"abstract":"The objective of this work was to optimize a chromatographic method, combining derivatization (silylation) with MSTFA (N-methyl-N-(trimethylsilyl)trifluoracetamide) and analysis by gas chromatography coupled to mass spectrometry (GC-MS), for the determination of hormones and UV filters selectively, evaluating the effect of derivatization on the chromatographic response. The method developed for the qualitative analysis (SCAN mode) allowed the identification of the analytes more accurately, with similarities of the spectra superior to 80%. The limits of detection and quantification ranged from 0.1 to 1.3 µg L-1 and 0.3 to 4.2 µg L-1 respectively. The quantitative method, combined silylation with chromatographic determination in SIM mode, proved to be precise (Relative standard deviation <7.2%) and exact (relative error <2.0%), with models without lack of fit, and with correlation coefficients linear values greater than 0.9, in accordance with the requirements and standards of the regulatory bodies.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42425652","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 : 2023-08-25DOI: 10.30744/brjac.2179-3425.ar-44-2023
B. Freire, Michael Monteiro, Jonatas de Oliveira S. Silva, José Fernando de Macedo, E. Sussuchi
This work aims to develop a modified electrode with N-doped carbon dots (CPE/N-CD) for the voltammetric detection of 17α-ethinylestradiol (EE2) in solution. N-doped carbon dot nanoparticles (N-CD) were synthesized using citric acid and urea as the nitrogen source. The N-doped carbon dots were characterized by absorption and emission spectroscopy in the ultraviolet and visible regions, electronic absorption spectroscopy in the infrared region, and Raman Spectroscopy, which showed evidence of the formation of the material. Electrochemical analyses were conducted utilizing Differential Pulse Voltammetry (DPV). After optimization of electrochemical parameters, a calibration plot was produced for the sensor, demonstrating a linear range of 0.01 to 0.80 μmol L-1 (R2 = 0.9969). Additionally, the sensor exhibited a detection limit (LOD) of 0.59 nmol L-1 and a quantification limit (LOQ) of 2.00 nmol L-1. The studies on reproducibility and repeatability revealed RSDs of 1.63% and 3.61% respectively. The results obtained using CPE/N-CD indicate that the developed electrode exhibits excellent analytical performance, making it suitable for identifying and quantifying EE2 in solution.
{"title":"Development of a Modified Electrode with N-doped Carbon Dots for Electrochemical Determination of 17α-ethinylestradiol","authors":"B. Freire, Michael Monteiro, Jonatas de Oliveira S. Silva, José Fernando de Macedo, E. Sussuchi","doi":"10.30744/brjac.2179-3425.ar-44-2023","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-44-2023","url":null,"abstract":"This work aims to develop a modified electrode with N-doped carbon dots (CPE/N-CD) for the voltammetric detection of 17α-ethinylestradiol (EE2) in solution. N-doped carbon dot nanoparticles (N-CD) were synthesized using citric acid and urea as the nitrogen source. The N-doped carbon dots were characterized by absorption and emission spectroscopy in the ultraviolet and visible regions, electronic absorption spectroscopy in the infrared region, and Raman Spectroscopy, which showed evidence of the formation of the material. Electrochemical analyses were conducted utilizing Differential Pulse Voltammetry (DPV). After optimization of electrochemical parameters, a calibration plot was produced for the sensor, demonstrating a linear range of 0.01 to 0.80 μmol L-1 (R2 = 0.9969). Additionally, the sensor exhibited a detection limit (LOD) of 0.59 nmol L-1 and a quantification limit (LOQ) of 2.00 nmol L-1. The studies on reproducibility and repeatability revealed RSDs of 1.63% and 3.61% respectively. The results obtained using CPE/N-CD indicate that the developed electrode exhibits excellent analytical performance, making it suitable for identifying and quantifying EE2 in solution.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49318629","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 : 2023-08-21DOI: 10.30744/brjac.2179-3425.ar-34-2023
Wilber Vilcapoma, Julio Pérez
Conventional methods used to quantify vitamin C require expensive equipment; however, the image analysis method has proven to be effective in quantifying various bioactive compounds and could be useful for small industries due to its low cost. In this sense, the objective was to evaluate the use of a Smartphone and image analysis in the quantification of vitamin C in golden berries juice. Calibration curves were elaborated with ascorbic acid standards (2.5-20 mg L-1) and the Folin-Ciocalteu chromophore reagent (10%). Fifteen color parameters (analytical responses) were obtained from images obtained with a Smartphone and the ImageJ program of the colored samples using four backlight colors, to which a principal component analysis was applied using the integrated development environment for R, RStudio. Subsequently, one-way ANOVA and mean comparisons by Tukey's method (α = 0.05) were applied to the best-scoring analytical response's. Ultimately, the quantification of vitamin C in golden berry juice was performed using the image analysis method, which exhibited superior linearity and sensitivity (R2 = 0.9941 and m = 4.91). A comparative assessment was conducted against a spectrophotometric method utilizing the t-Student test for independent samples (α = 0.05), demonstrating no statistically significant difference between the two methods (p > 0.05).
{"title":"Use of Smartphone and Image Analysis in the Quantification of Vitamin C in Golden Berry (Physalis peruviana L.) Juice","authors":"Wilber Vilcapoma, Julio Pérez","doi":"10.30744/brjac.2179-3425.ar-34-2023","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-34-2023","url":null,"abstract":"Conventional methods used to quantify vitamin C require expensive equipment; however, the image analysis method has proven to be effective in quantifying various bioactive compounds and could be useful for small industries due to its low cost. In this sense, the objective was to evaluate the use of a Smartphone and image analysis in the quantification of vitamin C in golden berries juice. Calibration curves were elaborated with ascorbic acid standards (2.5-20 mg L-1) and the Folin-Ciocalteu chromophore reagent (10%). Fifteen color parameters (analytical responses) were obtained from images obtained with a Smartphone and the ImageJ program of the colored samples using four backlight colors, to which a principal component analysis was applied using the integrated development environment for R, RStudio. Subsequently, one-way ANOVA and mean comparisons by Tukey's method (α = 0.05) were applied to the best-scoring analytical response's. Ultimately, the quantification of vitamin C in golden berry juice was performed using the image analysis method, which exhibited superior linearity and sensitivity (R2 = 0.9941 and m = 4.91). A comparative assessment was conducted against a spectrophotometric method utilizing the t-Student test for independent samples (α = 0.05), demonstrating no statistically significant difference between the two methods (p > 0.05).","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48842730","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}
Due to its better sensitivity and selectivity, liquid chromatography with tandem mass spectrometry is the preferred choice for the quantification and identification of biomarkers, parent molecules/ metabolites in human saliva, plasma and urine etc. All such quantification methods for melatonin in biological matrices have been summarized. Melatonin is considered as a potential biomarker for circadian rhythm disturbance related disorders such as cancer, depression, Insomnia, etc. Accurate quantification of melatonin is very challenging and critically depends upon the reproducibility and ruggedness of the analytical method. LC-MS/MS technique is considered as the preferred method of analysis for melatonin as compared to immunoassays. Most of bioanalytical melatonin quantification methods consist of, extraction from the biological matrix analyzing by LC-MS/MS. Our review shows that LC-MS/MS is a rugged and dependable instrument for the robust and precise quantitation of Melatonin. This review compiles key elements like extraction procedure, linearity range, and chromatographic conditions.
{"title":"A Brief Assessment of the Bioanalytical Methods by using LC-MS/MS for the Quantitation of Melatonin: A Potential Biomarker for Sleep-Related Disorders","authors":"Gorav Monga, Sravani Yerram, Shailaja Koppula, Rakesh Kumar, Sandeep Kumar","doi":"10.30744/brjac.2179-3425.rv-143-2022","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.rv-143-2022","url":null,"abstract":"Due to its better sensitivity and selectivity, liquid chromatography with tandem mass spectrometry is the preferred choice for the quantification and identification of biomarkers, parent molecules/ metabolites in human saliva, plasma and urine etc. All such quantification methods for melatonin in biological matrices have been summarized. Melatonin is considered as a potential biomarker for circadian rhythm disturbance related disorders such as cancer, depression, Insomnia, etc. Accurate quantification of melatonin is very challenging and critically depends upon the reproducibility and ruggedness of the analytical method. LC-MS/MS technique is considered as the preferred method of analysis for melatonin as compared to immunoassays. Most of bioanalytical melatonin quantification methods consist of, extraction from the biological matrix analyzing by LC-MS/MS. Our review shows that LC-MS/MS is a rugged and dependable instrument for the robust and precise quantitation of Melatonin. This review compiles key elements like extraction procedure, linearity range, and chromatographic conditions.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44470906","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 : 2023-07-28DOI: 10.30744/brjac.2179-3425.tn-22-2023
Flávio Bezerra, Y. Sade, Jailton Damasceno, Renata Silva
Warfarin (WAR), brodifacoum (BDF) and bromadiolone (BDL) are compounds present in rodenticides, highly toxic to rats, humans and other animals. These compounds can be detected in complex matrices, such as stomach contents, by liquid chromatography techniques (HPLC) with mass spectrometry (MS) or fluorescence detection (FLD). However, no validated method showed determination of uncertainty in the quantification of these compounds. In this study, we compare the validation parameters of two analytical methods, HPLC FLD and ultra high performance liquid chromatography (UHPLC – MS), with uncertainty estimation for the three cited compounds. The results showed that UHPLC-MS outperformed HPLC FLD, however both methods were considered adequate for detection of WAR, BDF or BDL in samples of simulated human stomach contents, especially in cases of suspected contamination.
{"title":"Validation and Uncertainty Calculation of Rodenticide Analysis Methods in a Simulated Gastric Content Matrix – Uncertainty of Rodenticide Analysis Methods","authors":"Flávio Bezerra, Y. Sade, Jailton Damasceno, Renata Silva","doi":"10.30744/brjac.2179-3425.tn-22-2023","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.tn-22-2023","url":null,"abstract":"Warfarin (WAR), brodifacoum (BDF) and bromadiolone (BDL) are compounds present in rodenticides, highly toxic to rats, humans and other animals. These compounds can be detected in complex matrices, such as stomach contents, by liquid chromatography techniques (HPLC) with mass spectrometry (MS) or fluorescence detection (FLD). However, no validated method showed determination of uncertainty in the quantification of these compounds. In this study, we compare the validation parameters of two analytical methods, HPLC FLD and ultra high performance liquid chromatography (UHPLC – MS), with uncertainty estimation for the three cited compounds. The results showed that UHPLC-MS outperformed HPLC FLD, however both methods were considered adequate for detection of WAR, BDF or BDL in samples of simulated human stomach contents, especially in cases of suspected contamination.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41473869","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 : 2023-07-21DOI: 10.30744/brjac.2179-3425.ar-38-2023
Natália Viola, Brian Ferreira, L. Souza, M. Veiga
This study proposes a matrix separation procedure based on micellar-mediated extraction (cloud point extraction - CPE) for determining As, Cd, Pb, and Se (potential contaminants) in nickel alloy and steel samples. Structural characterization and qualitative analysis of Ni alloy were conducted on the nickel alloy using scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM-EDS). After sample decomposition, ammonium o,o-diethyl dithiophosphate (DDTP) was used to complex the analytes and Triton X-114 as a non-ionic surfactant in CPE for matrix separation and extraction. Methanol acidified with 0.1 mol L-1 HNO3 was added to the surfactant-rich phase before the analytes determination by graphite furnace atomic absorption spectrometry (GF AAS). Parameters such as pH, complexing agent and surfactant concentrations, acid medium, complexation time, and type of diluent were evaluated. The obtained results indicated that the ratio DDTP:As was 3:1, DDTP:Cd and DDTP:Pb was 2:1, and DDTP:Se was 1:1. The enrichment factors were 6, 8, 14, and 13, and limits of detection were 1.5, 0.06, 0.31 and 0.27 µg g-1 for As, Cd, Pb, and Se, respectively. The method was applied for As, Cd, Pb, and Se determination in Inconel 625 nickel alloy and standard reference materials (AISI 4340 Steel - SRM® 361, AISI 94B17 Steel - SRM® 362, Chromium-Vanadium Steel - SRM® 363, and Nickel Alloy UNS - SRM® 864). Analyte recoveries lay above 88%, and relative standard deviations were lower than 5%. Application of cloud point extraction for matrix separation allowed the determination of low concentrations of As, Cd, Pb, and Se, constituting an environmentally friendly method.
{"title":"Systematic Study for Determining As, Pb, Cd, and Se in Steel and Nickel Alloy Samples by GF AAS: Circumventing Matrix Interference with Extraction Based on Micellar Separation","authors":"Natália Viola, Brian Ferreira, L. Souza, M. Veiga","doi":"10.30744/brjac.2179-3425.ar-38-2023","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-38-2023","url":null,"abstract":"This study proposes a matrix separation procedure based on micellar-mediated extraction (cloud point extraction - CPE) for determining As, Cd, Pb, and Se (potential contaminants) in nickel alloy and steel samples. Structural characterization and qualitative analysis of Ni alloy were conducted on the nickel alloy using scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM-EDS). After sample decomposition, ammonium o,o-diethyl dithiophosphate (DDTP) was used to complex the analytes and Triton X-114 as a non-ionic surfactant in CPE for matrix separation and extraction. Methanol acidified with 0.1 mol L-1 HNO3 was added to the surfactant-rich phase before the analytes determination by graphite furnace atomic absorption spectrometry (GF AAS). Parameters such as pH, complexing agent and surfactant concentrations, acid medium, complexation time, and type of diluent were evaluated. The obtained results indicated that the ratio DDTP:As was 3:1, DDTP:Cd and DDTP:Pb was 2:1, and DDTP:Se was 1:1. The enrichment factors were 6, 8, 14, and 13, and limits of detection were 1.5, 0.06, 0.31 and 0.27 µg g-1 for As, Cd, Pb, and Se, respectively. The method was applied for As, Cd, Pb, and Se determination in Inconel 625 nickel alloy and standard reference materials (AISI 4340 Steel - SRM® 361, AISI 94B17 Steel - SRM® 362, Chromium-Vanadium Steel - SRM® 363, and Nickel Alloy UNS - SRM® 864). Analyte recoveries lay above 88%, and relative standard deviations were lower than 5%. Application of cloud point extraction for matrix separation allowed the determination of low concentrations of As, Cd, Pb, and Se, constituting an environmentally friendly method.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45407081","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 : 2023-07-10DOI: 10.30744/brjac.2179-3425.interview.jszpunar
J. Szpunar
Joanna Szpunar graduated from the Warsaw University of Technology in 1986 and obtained her Ph.D. (1992) and D.Sc. (Habilitation) (2000) from the University of Warsaw. Since 1997, she works at the National Research Council of France (CNRS). In 2007, she obtained in Poland the title of professor of chemistry. She has broad experience in the field of mass spectrometry-based bio-inorganic speciation analysis and metallomics with a focus on the identification and quantification of trace element species in biological systems and in the chemistry of metal-biomolecule interactions. She is the co-author of a book and approximately 250 scientific publications in peer-reviewed international journals. Joanna Szpunar is a fellow of the Royal Society of Chemistry (UK) and has been, for many years, a member of the boards of Journal of Analytical Atomic Spectrometry' and Metallomics. She regularly gives invited lectures at international analytical chemistry meetings and was the chairperson of the European Winter Conference on Plasma Spectrochemistry (Kraków, Poland) in 2013. The investigations carried out under her supervision and/or with her active participation resulted in the identification of a number of molecular targets of metals in biological systems, as well as contribute to selenometabolomics and selenoproteomics studies in bacteria and plants. In recent years, her interests were broadened to the environmental fate of metal-containing nanoparticles and nanoplastics. She has supervised 12 Ph.D. theses and several post-doctoral fellows. Joanna Szpunar is the laureate of the 2013 Jerzy Fijalkowski Award of the Committee of Analytical Chemistry of the Polish Academy of Sciences and the 2017 European Award for Plasma Spectrochemistry. In recent years, Joanna Szpunar has been involved in collaboration with analytical chemists in Brazil, hosting graduate students from the University of Campinas and the Federal University of Pelotas in the laboratory at the Institute of Analytical Sciences (IPREM) in Pau afiliated with the CNRS, lecturing at the Federal University of Santa Maria and co-supervising a Ph.D. student with work carried out at the University of Pau and the Federal University of Pelotas.
{"title":"Joanna Szpunar, a great chemical researcher internationally recognized, kindly spoke to BrJAC","authors":"J. Szpunar","doi":"10.30744/brjac.2179-3425.interview.jszpunar","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.interview.jszpunar","url":null,"abstract":"Joanna Szpunar graduated from the Warsaw University of Technology in 1986 and obtained her Ph.D. (1992) and D.Sc. (Habilitation) (2000) from the University of Warsaw. Since 1997, she works at the National Research Council of France (CNRS). In 2007, she obtained in Poland the title of professor of chemistry. She has broad experience in the field of mass spectrometry-based bio-inorganic speciation analysis and metallomics with a focus on the identification and quantification of trace element species in biological systems and in the chemistry of metal-biomolecule interactions. She is the co-author of a book and approximately 250 scientific publications in peer-reviewed international journals. Joanna Szpunar is a fellow of the Royal Society of Chemistry (UK) and has been, for many years, a member of the boards of Journal of Analytical Atomic Spectrometry' and Metallomics. She regularly gives invited lectures at international analytical chemistry meetings and was the chairperson of the European Winter Conference on Plasma Spectrochemistry (Kraków, Poland) in 2013. The investigations carried out under her supervision and/or with her active participation resulted in the identification of a number of molecular targets of metals in biological systems, as well as contribute to selenometabolomics and selenoproteomics studies in bacteria and plants. In recent years, her interests were broadened to the environmental fate of metal-containing nanoparticles and nanoplastics. She has supervised 12 Ph.D. theses and several post-doctoral fellows. Joanna Szpunar is the laureate of the 2013 Jerzy Fijalkowski Award of the Committee of Analytical Chemistry of the Polish Academy of Sciences and the 2017 European Award for Plasma Spectrochemistry. In recent years, Joanna Szpunar has been involved in collaboration with analytical chemists in Brazil, hosting graduate students from the University of Campinas and the Federal University of Pelotas in the laboratory at the Institute of Analytical Sciences (IPREM) in Pau afiliated with the CNRS, lecturing at the Federal University of Santa Maria and co-supervising a Ph.D. student with work carried out at the University of Pau and the Federal University of Pelotas.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41611986","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 : 2023-07-10DOI: 10.30744/brjac.2179-3425.editorial.women.chem.n40
M. D. da Veiga, M. D. G. Korn
Women's participation in science has been an increasingly relevant and discussed topic in recent decades. Throughout history, women have faced numerous barriers and challenges to enter and stand out in this field of knowledge. However, despite the difficulties, women have contributed significantly to scientific advancement in all areas. In Brazil, the discussion about the participation of women in science has been highlighted in national events around analytical chemistry and academia. Thus, some changes have been implemented to minimize the differences discussed herein. Today we see more and more women engaged in science, holding prominent positions as researchers, professors, and leaders in their fields. They exist in many scientific disciplines, including physics, chemistry, biology, mathematics, engineering, and technology. In addition, women have also been involved in emerging and interdisciplinary areas such as computer science, artificial intelligence, and biotechnology. It is crucial to promote gender equality in chemistry by providing an inclusive environment and encouraging the active participation of women. This can be achieved by implementing policies that promote equal opportunities, encouraging female role models and mentors, supporting women chemists' training and professional development, and valuing and recognizing their contributions. Women's participation in chemistry is essential to scientific advancement in this field. We bring unique perspectives, creativity, and skills to address chemical challenges and contribute to a more comprehensive understanding of chemical processes and their practical applications. Gender diversity in chemistry drives innovation and promotes a more prosperous and inclusive scientific environment. It is essential to provide equal opportunities, support, and encouragement for women to enter and thrive in academic careers in the exact sciences, thus strengthening female representation in this field and boosting scientific excellence. In this context, the BrJAC journal worked on organizing an issue dedicated to women researchers in the field of (bio)analytical chemistry. The central idea is to celebrate those female researchers who have worked hard and dedicatedly in analytical chemistry. The interview was with Dr. Joanna Szpunar from the National Research Council of France (CNRS). She talked about her career and experience as a prominent researcher in the spectroanalytical chemistry field. The point of view was with Dr. Maria Valnice Boldrin Zanoni from UNESP, who excels in electroanalytical chemistry and shares a new perspective on artificial photosynthesis technology. The Letter written by Dr. Quezia Cass from UFSCar presented us with text on separation techniques highlighting affinity selection mass spectrometry. The issue will also feature three reviews, eight articles, and three technical notes, all led by women in (bio)analytical chemistry. It is imperative to thank all the reviewers who particip
{"title":"Women in (Bio)Analytical Chemistry: Moving Towards Equity and Inclusion","authors":"M. D. da Veiga, M. D. G. Korn","doi":"10.30744/brjac.2179-3425.editorial.women.chem.n40","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.editorial.women.chem.n40","url":null,"abstract":"Women's participation in science has been an increasingly relevant and discussed topic in recent decades. Throughout history, women have faced numerous barriers and challenges to enter and stand out in this field of knowledge. However, despite the difficulties, women have contributed significantly to scientific advancement in all areas. In Brazil, the discussion about the participation of women in science has been highlighted in national events around analytical chemistry and academia. Thus, some changes have been implemented to minimize the differences discussed herein. Today we see more and more women engaged in science, holding prominent positions as researchers, professors, and leaders in their fields. They exist in many scientific disciplines, including physics, chemistry, biology, mathematics, engineering, and technology. In addition, women have also been involved in emerging and interdisciplinary areas such as computer science, artificial intelligence, and biotechnology. It is crucial to promote gender equality in chemistry by providing an inclusive environment and encouraging the active participation of women. This can be achieved by implementing policies that promote equal opportunities, encouraging female role models and mentors, supporting women chemists' training and professional development, and valuing and recognizing their contributions. Women's participation in chemistry is essential to scientific advancement in this field. We bring unique perspectives, creativity, and skills to address chemical challenges and contribute to a more comprehensive understanding of chemical processes and their practical applications. Gender diversity in chemistry drives innovation and promotes a more prosperous and inclusive scientific environment. It is essential to provide equal opportunities, support, and encouragement for women to enter and thrive in academic careers in the exact sciences, thus strengthening female representation in this field and boosting scientific excellence. In this context, the BrJAC journal worked on organizing an issue dedicated to women researchers in the field of (bio)analytical chemistry. The central idea is to celebrate those female researchers who have worked hard and dedicatedly in analytical chemistry. The interview was with Dr. Joanna Szpunar from the National Research Council of France (CNRS). She talked about her career and experience as a prominent researcher in the spectroanalytical chemistry field. The point of view was with Dr. Maria Valnice Boldrin Zanoni from UNESP, who excels in electroanalytical chemistry and shares a new perspective on artificial photosynthesis technology. The Letter written by Dr. Quezia Cass from UFSCar presented us with text on separation techniques highlighting affinity selection mass spectrometry. The issue will also feature three reviews, eight articles, and three technical notes, all led by women in (bio)analytical chemistry. It is imperative to thank all the reviewers who particip","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46597649","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 : 2023-07-03DOI: 10.30744/brjac.2179-3425.tn-31-2023
Maria Alice Amaral, M. Fusinato, Michele da Cunha, Jean Paulo Coll, João Henrique Lacerda, P. S. Sanches Filho
Emerging contaminants (EC) can be harmful to human health and the environment, as many of these compounds are persistent, bioaccumulative, toxic and are not regulated. Drugs are part of this group, including hormones (estrone, β-estradiol) and sunscreens (oxybenzone and octocrylene) used in this study. The adsorption capacity of biochar generated from the pyrolysis of rice husks from the region of Pelotas-RS-Brazil was evaluated in this study. The objective was to characterize the biochar and evaluate its adsorbent potential in the removal of hormones and sunscreens. The characterization of biochar was carried out through surface area (BET), Zero charge point (ZPC), X-ray diffraction (XFR), fixed carbon, volatile, and ash. The effectiveness in removing ECs was evaluated by stirring rice husk pyrolysis biochar (RHPB) (0.2 g and 0.5 g) in synthetic aqueous solutions fortified with 10.0 µg L-1 of the analytes at 25 °C for 1 hour at 150 rpm. The RHPB was filtered off and the analytes were desorbed with acetone and dichloromethane (DCM) under ultrasound for 30 min. The extract was concentrated, derivatized by silylation, and analyzed by gas chromatography coupled to mass spectrometry (GC-MS). Biochar showed promising removal results, reaching values of 60.1% removal for β-estradiol, 59.4% for estrone, 44.6% for octocrylene and 37.4% for oxybenzone.
新出现的污染物(EC)可能对人类健康和环境有害，因为其中许多化合物具有持久性、生物蓄积性、毒性且不受管制。药物是这一组的一部分，包括激素(雌酮，β-雌二醇)和防晒霜(氧苯酮和八烯)在这项研究中使用。本研究对Pelotas-RS-Brazil地区稻壳热解产生的生物炭的吸附能力进行了评价。目的是表征生物炭并评估其在去除激素和防晒霜方面的吸附潜力。通过比表面积(BET)、零电荷点(ZPC)、x射线衍射(XFR)、固定碳、挥发分和灰分等指标对生物炭进行表征。稻壳热解生物炭(RHPB) (0.2 g和0.5 g)在添加10.0 μ g L-1分析物的合成水溶液中搅拌，在25°C、150 rpm下搅拌1小时，以评估其去除ECs的效果。过滤掉RHPB，超声下丙酮和二氯甲烷(DCM)解吸30 min，提取液浓缩，硅基化衍生，气相色谱-质谱联用(GC-MS)分析。生物炭对β-雌二醇的去除率为60.1%，对雌酮的去除率为59.4%，对八烯的去除率为44.6%，对氧苯酮的去除率为37.4%。
{"title":"Evaluation of the Adsorbent Potential of Biochar obtained by Pyrolysis to Remove Emerging Contaminants","authors":"Maria Alice Amaral, M. Fusinato, Michele da Cunha, Jean Paulo Coll, João Henrique Lacerda, P. S. Sanches Filho","doi":"10.30744/brjac.2179-3425.tn-31-2023","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.tn-31-2023","url":null,"abstract":"Emerging contaminants (EC) can be harmful to human health and the environment, as many of these compounds are persistent, bioaccumulative, toxic and are not regulated. Drugs are part of this group, including hormones (estrone, β-estradiol) and sunscreens (oxybenzone and octocrylene) used in this study. The adsorption capacity of biochar generated from the pyrolysis of rice husks from the region of Pelotas-RS-Brazil was evaluated in this study. The objective was to characterize the biochar and evaluate its adsorbent potential in the removal of hormones and sunscreens. The characterization of biochar was carried out through surface area (BET), Zero charge point (ZPC), X-ray diffraction (XFR), fixed carbon, volatile, and ash. The effectiveness in removing ECs was evaluated by stirring rice husk pyrolysis biochar (RHPB) (0.2 g and 0.5 g) in synthetic aqueous solutions fortified with 10.0 µg L-1 of the analytes at 25 °C for 1 hour at 150 rpm. The RHPB was filtered off and the analytes were desorbed with acetone and dichloromethane (DCM) under ultrasound for 30 min. The extract was concentrated, derivatized by silylation, and analyzed by gas chromatography coupled to mass spectrometry (GC-MS). Biochar showed promising removal results, reaching values of 60.1% removal for β-estradiol, 59.4% for estrone, 44.6% for octocrylene and 37.4% for oxybenzone.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42267295","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 : 2023-07-03DOI: 10.30744/brjac.2179-3425.ar-16-2023
Úrsula Méndez-Mejía, M. Tenorio, M. Jiménez-Reyes, Rosa Rodríguez-Tomp
This study focused on the examination of six rock pictorial panels and a solitary figure from four archaeological sites in the Sierra de las Cacachilas (Sector A) in the Region del Cabo, Baja California Sur, Mexico. Scanning Electron Microscopy-energy dispersive X-ray spectroscopy was utilized to analyze tiny samples of the pictorial layers, patina, rocky supports, and natural pigments. The concentrations of C, Mg, Al, Si, P, S, K, Ca, Cr, Ti, Mn, and Fe were subjected to statistical methods and the samples were divided into various clusters. Iron and calcium compounds appear to be the primary constituents of the pictorial layers. The red pigment spectra obtained through Fourier-transform infrared spectroscopy revealed the presence of inorganic compounds and the likelihood of a flora-based composite as the binding agent. The minerals identified through X-ray diffraction in the rocky supports were determined to be intrusive igneous rocks. These findings are significant for the conservation and preservation of the artwork in the Sierra de las Cacachilas.
{"title":"Ancient Rock Paintings at Region del Cabo-BCS, Mexico: An Analytical Study","authors":"Úrsula Méndez-Mejía, M. Tenorio, M. Jiménez-Reyes, Rosa Rodríguez-Tomp","doi":"10.30744/brjac.2179-3425.ar-16-2023","DOIUrl":"https://doi.org/10.30744/brjac.2179-3425.ar-16-2023","url":null,"abstract":"This study focused on the examination of six rock pictorial panels and a solitary figure from four archaeological sites in the Sierra de las Cacachilas (Sector A) in the Region del Cabo, Baja California Sur, Mexico. Scanning Electron Microscopy-energy dispersive X-ray spectroscopy was utilized to analyze tiny samples of the pictorial layers, patina, rocky supports, and natural pigments. The concentrations of C, Mg, Al, Si, P, S, K, Ca, Cr, Ti, Mn, and Fe were subjected to statistical methods and the samples were divided into various clusters. Iron and calcium compounds appear to be the primary constituents of the pictorial layers. The red pigment spectra obtained through Fourier-transform infrared spectroscopy revealed the presence of inorganic compounds and the likelihood of a flora-based composite as the binding agent. The minerals identified through X-ray diffraction in the rocky supports were determined to be intrusive igneous rocks. These findings are significant for the conservation and preservation of the artwork in the Sierra de las Cacachilas.","PeriodicalId":9115,"journal":{"name":"Brazilian Journal of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49095932","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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