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1.
Foods ; 13(15)2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39123588

RESUMO

The cacao fruit is a rich source of polyphenols, including flavonoids and phenolic acids, which possess significant health benefits. The accurate identification and quantification of these bioactive compounds extracted from different parts of the cacao fruit, such as pods, beans, nibs, and cacao shells, require specific treatment conditions and analytical techniques. This review presents a comprehensive comparison of extraction processes and analytical techniques used to identify and quantify polyphenols from various parts of the cacao fruit. Additionally, it highlights the environmental impact of these methods, exploring the challenges and opportunities in selecting and utilizing extraction, analytical, and impact assessment techniques, while considering polyphenols' yield. The review aims to provide a thorough overview of the current knowledge that can guide future decisions for those seeking to obtain polyphenols from different parts of the cacao fruit.

2.
Arch Microbiol ; 206(4): 185, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38506928

RESUMO

This review provides a comprehensive overview of the key aspects of the natural metabolite production by endophytic fungi, which has attracted significant attention due to its diverse biological activities and wide range of applications. Synthesized by various fungal species, these metabolites encompass compounds with therapeutic, agricultural, and commercial significance. We delved into strategies and advancements aimed at optimizing fungal metabolite production. Fungal cultivation, especially by Aspergillus, Penicillium, and Fusarium, plays a pivotal role in metabolite biosynthesis, and researchers have explored both submerged and solid-state cultivation processes to harness the full potential of fungal species. Nutrient optimization, pH, and temperature control are critical factors in ensuring high yields of the targeted bioactive metabolites especially for scaling up processes. Analytical methods that includes High-Performance Liquid Chromatography (HPLC), Liquid Chromatography-Mass Spectrometry (LC-MS), Gas Chromatography-Mass Spectrometry (GC-MS), Nuclear Magnetic Resonance (NMR), and Mass Spectrometry (MS), are indispensable for the identification and quantification of the compounds. Moreover, genetic engineering and metabolic pathway manipulation have emerged as powerful tools to enhance metabolite production and develop novel fungal strains with increased yields. Regulation and control mechanisms at the genetic, epigenetic, and metabolic levels are explored to fine-tune the biosynthesis of fungal metabolites. Ongoing research aims to overcome the complexity of the steps involved to ensure the efficient production and utilization of fungal metabolites.


Assuntos
Fungos , Redes e Vias Metabólicas , Espectrometria de Massas , Fungos/genética , Fungos/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas
3.
Biomed Chromatogr ; 38(3): e5746, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37723598

RESUMO

The general population and workers are exposed to organophosphate insecticides, one of the leading chemical classes of pesticides used in rural and urban areas. This paper aims to conduct an integrative review of the most used analytical methods for identifying and quantifying dialkylphosphate-which are metabolites of organophosphate insecticides-in the urine of exposed workers, discussing their advantages, limitations and applicability. Searches utilized the PubMed, the Scientific Electronic Library Online and the Brazilian Digital Library of Theses and Dissertations databases between 2000 and 2021. Twenty-five studies were selected. The extraction methods most used were liquid-liquid extraction (LLE) (36%) and solid-phase extraction (SPE) (36%), with the SPE being more economical in terms of time and amount of solvents needed, and presenting the best percentage of recovery of analytes, when compared with LLE. Nineteen studies (76%) used the gas chromatography method of separation, and among these, 12 records (63%) indicated mass spectrometry used as a detection technology (analyzer). Studies demonstrate that dialkylphosphates are sensitive and representative exposure biomarkers for environmental and occupational organophosphate exposure.


Assuntos
Inseticidas , Praguicidas , Humanos , Inseticidas/análise , Cromatografia Gasosa-Espectrometria de Massas , Compostos Organofosforados/análise , Organofosfatos/urina
4.
Toxics ; 11(12)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38133348

RESUMO

We provide an extensive review of 17 independent and industry-funded studies targeting carbonyls in aerosol emissions of Heated Tobacco Products (HTPs), focusing on quality criteria based on the reproducibility of experiments, appropriate analytic methods, and puffing regimes. Most revised studies complied with these requirements, but some were unreproducible, while others failed to consider analytical variables that may have affected the results and/or produced unrealistic comparisons. We also provide a review of the literature on the physicochemical properties of heated tobacco and HTP aerosols, as well as the evaluation of HTPs by regulatory agencies, addressing various critiques of their relative safety profile. The outcomes from the revised studies and regulatory evaluations tend to agree with and converge to a general consensus that HTP aerosols expose users to significantly lower levels of toxicity than tobacco smoke.

5.
Crit Rev Anal Chem ; : 1-9, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37990513

RESUMO

The drug rapamycin is a potent inhibitor of the mTOR complex, acting directly in the signaling cascade of this protein complex; interrupting cell proliferation, in addition to being an extremely efficient immunosuppressant. Currently this drug is being used in several types of cancer. Rapamycin has been a target of great interest within nanomedicine involving nanostructured systems for drug delivery aiming to increase the bioactivity and bioavailability of this drug. In addition, there is a constant search for analytical methods to identify and quantify this drug. Numerous high-performance liquid chromatography analytical techniques, mass spectrometry and immunoassay techniques have been employed efficiently in an attempt to develop increasingly sensitive analytical methods. Thus, this review sought to bring together current and relevant scientific works involving rapamycin and; besides analytical methods more used for quantification of this molecule.

6.
Curr Pharm Des ; 29(30): 2369-2376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37859323

RESUMO

BACKGROUND: Azithromycin (AZT) is an antimicrobial available in different pharmaceutical forms and many people can have access to this medicine. Therefore, the existence of adequate and reliable analytical methods for evaluating the quality of AZT and AZT-based products is essential. OBJECTIVE/METHODS: The purpose of this review is to discuss the analytical methods for evaluating AZT present in the literature and official compendia in the context of Green Analytical Chemistry (GAC). RESULTS: Among the methods found in the literature for evaluating AZT, the most used method is HPLC (62%) followed by TLC (14%) and the microbiological method by agar diffusion (14%). Even pharmacopoeias recommend the analysis of AZT by HPLC or agar diffusion. Acetonitrile and methanol account for 35% of the most used solvents in the analyses, followed by buffer. CONCLUSION: AZT lacks analytical methods in the context of GAC. Both physical-chemical and microbiological methods can contemplate the environmentally friendly way to analyze AZT and AZT-based products, depending only on the chosen conditions. Ethanol, purified water, acetic acid instead of methanol, acetonitrile, buffer, formic acid in the physical-chemical methods are excellent alternatives. However, in the microbiological method, turbidimetry is a great option instead of agar diffusion.


Assuntos
Anti-Infecciosos , Azitromicina , Humanos , Metanol , Ágar , Acetonitrilas
7.
Artigo em Inglês | MEDLINE | ID: mdl-37640447

RESUMO

Members within the Fusarium sambucinum species complex (FSAMSC) are able to produce mycotoxins, such as deoxynivalenol (DON), nivalenol (NIV), zearalenone (ZEN) and enniatins (ENNs) in food products. Consequently, alternative methods for assessing the levels of these mycotoxins are relevant for quick decision-making. In this context, qPCR based on key mycotoxin biosynthetic genes could aid in determining the toxigenic fungal biomass, and could therefore infer mycotoxin content. The aim of this study was to verify the use of qPCR as a technique for estimating DON, NIV, ENNs and ZEN, as well as Fusarium graminearum sensu lato (s.l.) and F. poae in barley grains. For this purpose, 53 barley samples were selected for mycobiota, mycotoxin and qPCR analyses. ENNs were the most frequent mycotoxins, followed by DON, ZEN and NIV. 83% of the samples were contaminated by F. graminearum s.l. and 51% by F. poae. Pearson correlation analysis showed significant correlations for TRI12/15-ADON with DON, ESYN1 with ENNs, TRI12/15-ADON and ZEB1 with F. graminearum s.l., as well as ESYN1 and TRI12/NIV with F. poae. Based on the results, qPCR could be useful for the assessment of Fusarium presence, and therefore, provide an estimation of its mycotoxins' levels from the same sample.


Assuntos
Fusarium , Hordeum , Micotoxinas , Zearalenona , Micotoxinas/análise , Fusarium/genética , Zearalenona/análise , Reação em Cadeia da Polimerase/métodos , Grão Comestível/química
8.
Revista Científica ANMAT ; 408/2023. graf., tab
Artigo em Espanhol | BINACIS | ID: biblio-1510031

RESUMO

La determinación de proteínas totales es una técnica de rutina utilizada en la industria biofarmacéutica durante los procesos de purificación de derivados plasmáticos y/o producción de proteínas recombinantes; y la elección del método analítico es un paso crítico para la obtención de resultados confiables. En este trabajo se demostró la interferencia de heparina (Hep), un compuesto comúnmente utilizado como excipiente en la formulación de Concentrados de Factores de la Coagulación (CFC), en la determinación de proteínas por el método de Bradford, cuya interferencia no está descripta como tal en los insertos de los kits comerciales de Bradford ni en la Farmacopea Europea. Esta interferencia fue demostrada tanto en soluciones de Albúmina Sérica Bovina (BSA) fortificadas con Hep, como en muestras de CFC. Para una solución de BSA 40 mg %, la concentración límite de Hep que no interfiere en la determinación de proteínas totales fue de 1,6 UI/ml. Cabe destacar que, si se trabaja a un nivel menor de concentración de proteínas, una proteína diferente o mezclas complejas de proteínas, se debe evaluar el grado de interferencia para cada caso particular, pudiéndose utilizar los valores obtenidos en este trabajo como referencia. Alternativamente, se evaluó la neutralización de la Hep con Polybrene (Poly), previo a la determinación de proteínas por Bradford. En el caso de soluciones de BSA, el efecto interferente se revirtió logrando una correcta cuantificación de proteínas, mientras que en las muestras de CFC, la neutralización con Poly no fue efectiva. Por lo tanto, para considerar el uso de Poly, previo a la aplicación del método de Bradford, debe evaluarse cada caso particular según las características de la muestra proteica en estudio. Si esto no es posible, se recomienda la utilización de un método alternativo, por ejemplo, el colorimétrico que utiliza ácido bicinconínico.


Protein quantification in biological samples is a routine assay used in the biopharmaceutical industry during the purification procedures of plasma-derived products and/or recombinant proteins. Thus, choosing the method for this purpose is a critical step to obtaining reliable results. In this work, it was shown that Heparin (Hep), a compound commonly used as an excipient in the formulation step of Coagulation Factor Concentrates (CFC), interferes in protein quantification by the Bradford assay. This interference was proved both in solutions of Hep-fortified Bovine Serum Albumin (BSA) and in CFC samples. For a 40 mg % BSA solution, the Hep concentration which shows no interference in protein quantification is 1.6 IU/ml. It should be noted that a specific analysis must be carried out if working at a lower protein concentration, with a different protein, or with complex protein solutions, so the values obtained in this work can be used as a reference. Alternatively, Hep neutralization with Polybrene (Poly) was evaluated before protein determination by Bradford. In the case of BSA solutions, the interference was reversed and correct protein quantification was achieved, whereas in the CFC samples, the results were unsatisfactory. Until now, Hep interference in the Bradford assay has not been described in the scientific literature, nor listed in the inserts of the commercial kits for protein quantification by this method. It was concluded that for protein samples containing Hep, the choice of an alternative method, such as the one that uses bicinchoninic acid, is the most convenient option to obtain reliable results


Assuntos
Coagulação Sanguínea , Heparina , Proteínas , Métodos de Análise Laboratorial e de Campo
9.
Food Chem ; 429: 136974, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37499504

RESUMO

The intricate balance between the beneficial and harmful effects of selenium (Se) intake means that its quantification in food needs to be done correctly. Therefore, in this review, we systematized 105 articles to identify the most studied methodologies, analytical techniques, and food matrices. Among the analytical techniques employed, inductively coupled plasma mass spectrometry (ICP-MS) (n = 29) emerged as the most commonly used method. The most prevalent hydrolysis methodology to digest Se in food matrices involved the use of nitric acid combined with ultrasound, which improved both the yield and digestion time. Optimal recovery values were achieved when total Se quantification accounted for the sum of Se(IV) and Se(VI) (94.4-99.4%) and for SeCys (88-96.5%). These findings are relevant for advancing methodological approaches, and their results emphasize the importance of developing alternative, faster, and lower-cost protocols for Se quantification in foods and beverages.


Assuntos
Análise de Alimentos , Selênio/química , Bebidas/análise , Limite de Detecção
10.
Curr Pharm Des ; 29(15): 1166-1172, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37190804

RESUMO

Moxifloxacin (MOX) is a fourth-generation fluoroquinolone used in the form of tablets, infusion solutions and ophthalmic solutions. It does not have a physical-chemical or microbiological analytical method described in an official compendium. However, the literature shows some analysis methods for pharmaceuticals and biological matrices. In this context, the objective is to show the analytical methods present in the literature for the investigation of MOX by physical-chemical and microbiological techniques, as well as discussing them according to the requirements of current pharmaceutical analyses and green analytical chemistry. Among the physical-chemical methods present in the literature for MOX evaluation, 33% are HPLC, 21% are UV-Vis and 17% are capillary electrophoresis. On the other hand, among the microbiological methods, all of them are based on diffusion in agar. There is still scope in the literature to incorporate new and improved analytical methods for MOX evaluation, which adopt the concepts of green and sustainable analytical chemistry, either by using less (or not using) toxic organic solvents, reducing waste generation or even reducing the analysis time according to the intended objectives.


Assuntos
Técnicas Microbiológicas , Humanos , Moxifloxacina , Cromatografia Líquida de Alta Pressão
11.
Int J Biol Macromol ; 242(Pt 1): 124586, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37105249

RESUMO

Composite hydrogels containing nanofillers are extensively applied in the sorption of different compounds from aqueous solutions; however, this ability is poorly exploited in the extraction and pre-concentration of analytes from complex matrices. As a contribution to this field, this study reports the synthesis of a composite hydrogel of alginate-g-poly(acrylamide) matrix filled with functionalized multi-walled carbon nanotubes (ALG-g-PAAM/MWCNT-f). This composite served as a solid-phase extractor (SPE) for the separation of Pb2+ and Cd2+ ions from a digested corn cereal sample before their analytical determination. After composite characterization, a series of experiments using low dosages of ALG-g-PAAM/MWCNT-f demonstrated that the composite has a higher sorption capacity for Pb2+ (5.1 mg/g) and Cd2+ (3.9 mg/g) under favorable experimental conditions. As demonstrated, the presence of the MWCNT-f benefited the SPE performance of the composite. The sorption of both cations followed the pseudo-first order kinetics, while the experimental data were well-fitted by the Freundlich isotherm. Also, ALG-g-PAAM/MWCNT-f showed selectivity for Pb2+, and it is reusable up to 10 times without losing sorption performance. After sorption and extraction, both metals were completely recovered, facilitating their quantification by the MIP OES technique. In short, ALG-g-PAAM/MWCNT-f was an effective SPE for the separation and extraction of Pb2+ and Cd2+, which can be beneficial for food control and safety.


Assuntos
Hidrogéis , Nanotubos de Carbono , Zea mays , Grão Comestível , Cádmio , Alginatos , Chumbo , Cinética , Extração em Fase Sólida/métodos , Adsorção
12.
ABCS health sci ; 48: e023210, 14 fev. 2023. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1438253

RESUMO

INTRODUCTION: Phase angle (PhA) is a Bioelectrical impedance analysis (BIA) parameter representing an indicator of cellular health and has been suggested as a biomarker of nutritional status. OBJECTIVE: To evaluate the association between PhA and nutritional parameters in older adults. METHODS: A cross-sectional study was conducted with community-dwelling older adults. Body mass index (BMI), arm muscle circumference (AMC), calf circumference (CC), body fat percentage (BF%), appendicular skeletal muscle mass (ASMM), serum albumin, mini-nutritional assessment (MNA), and PhA were assessed. Kolmogorov­Smirnov test, Spearman's correlation coefficient, chi-square test, and Poisson regression models were performed. RESULTS: 144 participants were included in the study, and most of them were female, aged ≥80 years, and underweight. Most older adults with lower PhA were women, aged range 80­89 years, and with reduced ASMM (p<0.05). PhA presented a significant correlation with age (r=­0.417; p<0.001), ASMM (r=0.427; p<0.001), AMC (r=0.195; p=0.019) and BF% (r=­0.223; p=0.007). Older adults with lower PhA present reduced ASMM (PR: 1.25; 95%CI: 1.04­1.50), and hypoalbuminemia (PR: 1.50; 95%CI: 1.11­2.03). CONCLUSION: PhA is related to commonly nutritional indicators used in clinical practice and could be an important biomarker of muscle mass reserves in community-living older adults of both sexes.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Avaliação Nutricional , Estado Nutricional , Saúde do Idoso , Impedância Elétrica , Estudos Transversais
13.
Crit Rev Anal Chem ; 53(2): 384-395, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34396844

RESUMO

Veterinary medicinal products (VMPs) are used for the prevention and treatment of diseases in animals. The safety and efficacy of these products must be proven by quality control tests. Special attention should be paid to veterinary antimicrobials medicines (VAMs), as changes in their potency can compromise pharmacotherapeutic treatment and contribute to microbial resistance. The aim of this work was to review the analytical methods available for assessing the quality of VAMs, to analyze regulatory issues and quality control programs. The review was performed on selected papers in the PubMed, ScienceDirect, Scopus and Virtual Health Library databases, between 2005 and 2020. After applying exclusion criteria, 19 studies were obtained. Of the analytical studies, the majority (61.54%) used the HPLC technique. In addition, methods by CE (15.39%) and by SPM, FIA and microbiological assay (7.69% each) were found. In studies of monitoring of VAMs available on the market, changes in tylosin, spiramycin, ampicillin, tetracyclines and penicillins were observed. This is worrying, as these quality deviations can contribute to the development of resistant microorganisms. Although international efforts have been implemented at the regulatory level to ensure the quality of VAMs, it was realized with this study that there is much to evolve in the development of new analytical methods and in monitoring the quality of VAMs. With this, it is expected that this study will instigate scientists in the analytical, regulatory, microbiological and veterinary fields to develop new research so that the demands necessary to guarantee the quality of VAMs are increasingly met.


Assuntos
Anti-Infecciosos , Drogas Veterinárias , Animais , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Tilosina , Controle de Qualidade
14.
Crit Rev Anal Chem ; 53(3): 689-717, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34510987

RESUMO

Cocoa currently faces differentiation processes toward niches of specialty products, leading to greater competitiveness for producers who must compete with products differentiated by their integral quality regarding their organoleptic characteristics, such as fine-flavor cocoa and their functional characteristics. Quality is influenced by the genetic variety of the cultivars on the one hand, and the correct postharvest processing operations of cocoa seeds, on the other. During the transformation operations, the native chemical compounds of the seeds, especially proteins, carbohydrates, and polyphenols, are transformed and generate other compounds called flavor precursors, which are responsible for defining the product quality. In this sense, the analysis of the most relevant chemical compounds in cocoa is essential to guarantee higher overall quality. Similarly, understanding the fundamental aspects that affect fine-flavor cocoa production is crucial for improving transformation processes. Therefore, reliable and robust analytical techniques are required to detect and quantify these chemical compounds. This review highlights the main techniques used to analyze essential cocoa metabolites and derived products throughout all postharvest transformation stages: from cocoa seeds to chocolate bar, offering an overview of the sample preparation methods and the analytical and imaging methodologies often employed to characterize qualifying cocoa products.


Assuntos
Cacau , Chocolate , Chocolate/análise , Cacau/química , Cacau/genética , Sementes/química
15.
Rev. bras. zootec ; 52: e20220155, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1436807

RESUMO

The objective was to compare deoxynivalenol (DON) concentrations in feed ingredients and commercial swine diets measured by enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC). Seventy feed ingredient samples consisted of corn, corn dried distillers grains with solubles, corn gluten feed, corn gluten meal, palm kernel expellers, rice bran, soy hulls, soybean meal, and wheat. Commercial swine diet samples (n = 92) were collected from 23 swine farms of varying regions in Korea and different growth stages of pigs. The DON concentration of all samples was determined in duplicate. Statistical comparisons were performed to compare the analytical methods (ELISA vs. HPLC), diet phases, and regions. The DON concentrations in most ingredients and all diets determined by ELISA method were greater than those determined by HPLC. The DON concentrations determined by the ELISA method were less than 1 mg/kg in all ingredients except corn dried distillers grains with solubles and corn gluten feed, and those determined by the HPLC were less than 0.5 mg/kg in all ingredients. The DON concentrations in complete diets did not vary by region or growth stages of pigs. The DON concentrations in most feed ingredients and commercial swine diets determined by ELISA method are greater than those determined by HPLC, but does not vary by regions in Republic of Korea or pig growth stages.


Assuntos
Animais , Suínos , Ensaio de Imunoadsorção Enzimática , Dieta/veterinária , Ração Animal , Micotoxinas
16.
Food Res Int ; 157: 111366, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35761626

RESUMO

More than 5.8 million tonnes of oil have been spilled into the oceans. Some oil disasters marked history, causing multiple social and economic consequences in addition to catastrophic environmental impacts. Recently, Brazil and Mauritius faced oil disasters that have severely impacted seafood sanitary credibility. One of the components of the oil composition are the polycyclic aromatic hydrocarbons (PAH), which are the main contamination markers of petrogenic origin. There is enough evidence to correlate the intake of food contaminated with PAH with increased risks of developing cancer. The set PAH4, composed of benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, and chrysene, and the set PAH8, composed of benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[ghi]perylene, chrysene, dibenzo[a,h]anthracene, and indeno[1,2,3-cd]pyrene are recognized as markers of food chemical contamination. After oil disasters in the oceans, the risk to the health of seafood consumers tends to be of special concern, Countries like the European Union set maximum levels for benzo[a]pyrene (5 µg kg-1) and PAH4 (30 µg kg-1) in bivalve mollusks. Levels of concern established by countries that have faced oil disasters are given special attention in this review. Laboratory analysis of PAH in food samples is very challenging because it deals with quite different kinds of matrices. Furthermore, analytical results are usually related to the closure or reopening of cultivated areas and fishing points. Therefore, the progress of the analytical methods for PAH in seafood is covered in detail. Chemical laboratory measurements provide essential data to assess the potential risks to human health due to consumption of seafood contaminated with PAH. The main human health risk assessment approaches in a seafood contamination scenario with PAH are reviewed and discussed, providing an insightful and guiding tool to each step of the risk assessment framework.


Assuntos
Desastres , Poluição por Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Antracenos/análise , Benzo(a)pireno , Crisenos/análise , Inocuidade dos Alimentos , Humanos , Poluição por Petróleo/efeitos adversos , Poluição por Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
17.
Curr Pharm Des ; 28(18): 1501-1512, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35579160

RESUMO

5-Fluorouracil (5-FU) is an antimetabolite drug used for over 70 years as first-line chemotherapy to treat various types of cancer, such as head, neck, breast, and colorectal cancer. 5-FU acts mainly by inhibiting thymidylate synthase, thereby interfering with deoxyribonucleic acid (DNA) replication or by 5-FU incorporating into DNA, causing damage to the sequence of nucleotides. Being analogous to uracil, 5-FU enters cells using the same transport mechanism, where a is converted into active metabolites such as fluorouridine triphosphate (FUTP), fluorodeoxyuridine monophosphate (FdUMP), and fluorodeoxyuridine triphosphate (FdUTP). Currently, there are several nano delivery systems being developed and evaluated at the preclinical level to overcome existing limitations to 5-FU chemotherapy, including liposomes, polymeric nanoparticles, polymeric micelles, nanoemulsions, mesoporous silica nanoparticles, and solid lipid nanoparticles. Therefore, it is essential to choose and develop suitable analytical methods for the quantification of 5-FU and its metabolites (5- fluorouridine and 5-fluoro-2-deoxyuridine) in pharmaceutical and biological samples. Among the analytical techniques, chromatographic methods are commonly the most used for the quantification of 5-FU from different matrices. However, other analytical methods have also been developed for the determination of 5-FU, such as electrochemical methods, a sensitive, selective, and precise technique, in addition to having a reduced cost. Here, we first review the physicochemical properties, mechanism of action, and advances in 5-FU nanodelivery systems. Next, we summarize the current progress of other chromatographic methods described to determine 5- FU. Lastly, we discuss the advantages of electrochemical methods for the identification and quantification of 5- FU and its metabolites in pharmaceutical and biological samples.


Assuntos
Fluoruracila , Lipossomos , DNA , Fluoruracila/farmacologia , Humanos , Nanopartículas
18.
Toxicol Mech Methods ; 32(9): 637-649, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35387549

RESUMO

Compilation studies related to toxicological aspects and also biological monitoring and analysis methods for specific fungicides and, mainly, those that belong to the class of the dithiocarbamates (DTCs) have not been carried out at least in the last ten years. DTCs - dimethyldithiocarbamates, ethylenebisditiocarbamates, propylenebisditiocarbamates - are organosulfur compounds that form complexes due to the presence of different chemical elements, which bind strongly and inhibit enzymes that are essential to the functioning of the organism, causing a serious proven adverse effect on biological systems, such as alteration of thyroid hormones, teratogenesis and neurotoxicity. It is still evident, as shown by world data, that the growing consumption of fungicides has increasingly exposed the population in general and, in particular, workers who deal with these substances. There is a scarcity of studies in the literature discussing the toxicological and analytical aspects that are important for understanding the real effects of DTCs and monitoring human exposure to them. Therefore, the aim of this work was to expose, in a comprehensive way and through a narrative review, gaps in research related to the fungicides of the DTCs class, their metabolites, as well as the toxicological and analytical aspects involved. The review is divided into two parts: (1) Toxicological aspects, including toxicokinetics, toxicodynamics and toxidromes; and (2) Analytical Toxicology, which comprises biomarkers, sample preparation and identification/quantification methods.


Assuntos
Fungicidas Industriais , Fungicidas Industriais/toxicidade , Humanos , Toxicocinética
19.
Polymers (Basel) ; 14(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35267784

RESUMO

Lignin is one of the most studied and analyzed materials due to its importance in cell structure and in lignocellulosic biomass. Because lignin exhibits autofluorescence, methods have been developed that allow it to be analyzed and characterized directly in plant tissue and in samples of lignocellulose fibers. Compared to destructive and costly analytical techniques, fluorescence microscopy presents suitable alternatives for the analysis of lignin autofluorescence. Therefore, this review article analyzes the different methods that exist and that have focused specifically on the study of lignin because with the revised methods, lignin is characterized efficiently and in a short time. The existing qualitative methods are Epifluorescence and Confocal Laser Scanning Microscopy; however, other semi-qualitative methods have been developed that allow fluorescence measurements and to quantify the differences in the structural composition of lignin. The methods are fluorescence lifetime spectroscopy, two-photon microscopy, Föster resonance energy transfer, fluorescence recovery after photobleaching, total internal reflection fluorescence, and stimulated emission depletion. With these methods, it is possible to analyze the transport and polymerization of lignin monomers, distribution of lignin of the syringyl or guaiacyl type in the tissues of various plant species, and changes in the degradation of wood by pulping and biopulping treatments as well as identify the purity of cellulose nanofibers though lignocellulosic biomass.

20.
Artigo em Inglês | MEDLINE | ID: mdl-35262454

RESUMO

Polycyclic aromatic hydrocarbons (PAHs), the main component of petroleum, are a concern due to their environmental persistence, long-range transport, and potential toxic effects on animal, human health, and the environment. PAHs are considered persistent compounds and can be bioaccumulated in sediments and aquatic biota. Determining PAHs in animals and environmental samples consists of three steps: extraction, clean-up or purification, and analytical determination. The matrix complexity and the diversity of environmental contaminants, such as PAHs resulted in the development of numerous analytical techniques and protocols for the extraction of these components and analysis in several samples. This systematic review article seeks to relate the extraction and preparation methods of complex samples from aquatic animals and the two main detection techniques of PAHs. For the elaboration of the research, 67 articles published between 2011 and 2021 were sought, which specifically contemplated the isolation of aquatic extracts and detection and quantification techniques of PAHs.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Animais , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Policíclicos Aromáticos/análise
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