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1.
Front Immunol ; 12: 813082, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34956244

RESUMEN

Siglecs, a family of receptor-like lectins, recognize glycoproteins and/or glycolipids containing sialic acid in the extracellular space and transduce intracellular signaling. Recently, researchers uncovered significant contributions of Siglecs in cancer immunity, renewing interest in this family of proteins. Previous extensive studies have defined how Siglecs recognize glycan epitopes (glycotopes). Nevertheless, the biological role of these glycotopes has not been fully evaluated. Recent studies using live cells have begun unraveling the constituents of Siglec ligands. These studies demonstrated that glycoprotein scaffolds (counter-receptors) displaying glycotopes are sometimes just as important as the glycotope itself. These new insights may guide future efforts to develop therapeutic agents to target the Siglec - ligand axis.


Asunto(s)
Técnicas de Química Analítica/métodos , Técnicas de Química Analítica/tendencias , Cromatografía de Afinidad/métodos , Cromatografía de Afinidad/tendencias , Ligandos , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico , Animales , Humanos
2.
J Chromatogr A ; 1654: 462444, 2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-34380070

RESUMEN

This review article compares and contrasts sample preparation techniques coupled with high-performance liquid chromatography (HPLC) and describes applications developed in biomedical, forensics, and environmental/industrial hygiene in the last two decades. The proper sample preparation technique can offer valued data for a targeted application when coupled to HPLC and a suitable detector. Improvements in sample preparation techniques in the last two decades have resulted in efficient extraction, cleanup, and preconcentration in a single step, thus providing a pathway to tackle complex matrix applications. Applications such as biological therapeutics, proteomics, lipidomics, metabolomics, environmental/industrial hygiene, forensics, glycan cleanup, etc., have been significantly enhanced due to improved sample preparation techniques. This review looks at the early sample preparation techniques. Further, it describes eight sample preparation technique coupled to HPLC that has gained prominence in the last two decades. They are (1) solid-phase extraction (SPE), (2) liquid-liquid extraction (LLE), (3) gel permeation chromatography (GPC), (4) Quick Easy Cheap Effective Rugged, Safe (QuEChERS), (5) solid-phase microextraction (SPME), (6) ultrasonic-assisted solvent extraction (UASE), and (7) microwave-assisted solvent extraction (MWASE). SPE, LLE, GPC, QuEChERS, and SPME can be used offline and online with HPLC. UASE and MWASE can be used offline with HPLC but have also been combined with the online automated techniques of SPE, LLE, GPC, or QuEChERS for targeted analysis. Three application areas of biomedical, forensics, and environmental/industrial hygiene are reviewed for the eight sample preparation techniques. Three hundred and twenty references on the eight sample preparation techniques published over the last two decades (2001-2021) are provided. Other older references were included to illustrate the historical development of sample preparation techniques.


Asunto(s)
Técnicas de Química Analítica , Cromatografía Líquida de Alta Presión , Técnicas de Química Analítica/tendencias , Extracción Líquido-Líquido , Microextracción en Fase Sólida , Manejo de Especímenes
4.
J Chromatogr A ; 1651: 462307, 2021 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-34161837

RESUMEN

The difficulty of traditional Chinese medicine (TCM) researches lies in the complexity of components, metabolites, and bioactivities. For a long time, there has been a lack of connections among the three parts, which is not conducive to the systematic elucidation of TCM effectiveness. To overcome this problem, a classification-based methodology for simplifying TCM researches was refined from literature in the past 10 years (2011-2020). The theoretical basis of this methodology is set theory, and its core concept is classification. Its starting point is that "although TCM may contain hundreds of compounds, the vast majority of these compounds are structurally similar". The methodology is composed by research strategies for components, metabolites and bioactivities of TCM, which are the three main parts of the review. Technical route, key steps and difficulty are introduced in each part. Two perspectives are highlighted in this review: set theory is a theoretical basis for all strategies from a conceptual perspective, and liquid chromatography-mass spectrometry (LC-MS) is a common tool for all strategies from a technical perspective. The significance of these strategies is to simplify complex TCM researches, integrate isolated TCM researches, and build a bridge between traditional medicines and modern medicines. Potential research hotspots in the future, such as discovery of bioactive ingredients from TCM metabolites, are also discussed. The classification-based methodology is a summary of research experience in the past 10 years. We believe it will definitely provide support and reference for the following TCM researches.


Asunto(s)
Técnicas de Química Analítica/métodos , Cromatografía Liquida , Medicamentos Herbarios Chinos/química , Espectrometría de Masas , Medicina Tradicional China/tendencias , Técnicas de Química Analítica/tendencias , Humanos , Proyectos de Investigación
5.
Food Funct ; 12(8): 3433-3442, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33900344

RESUMEN

Cocoa flavanols (CF) are a group of dietary bioactives that have been studied for their potential health benefits for over two decades. In this time, multiple methods for CF testing have evolved, introducing the potential for differences in reported CF content. The reliable characterization of CF content in food and test materials used in clinical studies is critical to comparisons of research studies over time, as well as critical to enabling the systematic reviews and meta-analyses required to support dietary recommendations of bioactives. In this work, we compared two analytical methods that have been widely applied to characterize materials used in clinical research and a method newly recognized by AOAC as the official method for CF analysis. Differences in accuracy of -36% to +20% were observed when comparing CF contents determined with these methods, supporting the notion that CF values determined across methods are not directly comparable. To address differences, a linear regression model was developed to predict CF values. This approach was cross-validated and directly applied to the conversion of CF values published in key scientific papers on the benefits of CF. This work provides a valid tool to compare CF values reported across these different methods and enables comparisons and interpretation of studies investigating the bioactivity of CF.


Asunto(s)
Cacao/química , Técnicas de Química Analítica/normas , Técnicas de Química Analítica/tendencias , Flavonoles/análisis , Biflavonoides/análisis , Catequina/análisis , Técnicas de Química Analítica/métodos , Fitoquímicos/análisis , Proantocianidinas/análisis , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
6.
Biochem Soc Trans ; 48(6): 2457-2466, 2020 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-33336686

RESUMEN

Ion Mobility (IM) coupled to mass spectrometry (MS) is a useful tool for separating species of interest out of small quantities of heterogenous mixtures via a combination of m/z and molecular shape. While tandem MS instruments are common, instruments which employ tandem IM are less so with the first commercial IM-MS instrument capable of multiple IM selection rounds being released in 2019. Here we explore the history of tandem IM instruments, recent developments, the applications to biological systems and expected future directions.


Asunto(s)
Espectrometría de Movilidad Iónica/instrumentación , Espectrometría de Movilidad Iónica/métodos , Espectrometría de Masas en Tándem/instrumentación , Espectrometría de Masas en Tándem/métodos , Biofisica/historia , Biofisica/tendencias , Técnicas de Química Analítica/historia , Técnicas de Química Analítica/tendencias , Diseño de Equipo , Historia del Siglo XX , Historia del Siglo XXI , Espectrometría de Movilidad Iónica/tendencias , Iones , Espectrometría de Masas en Tándem/tendencias
7.
J Pharm Biomed Anal ; 191: 113597, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-32927419

RESUMEN

The multiple pathological effects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and its total novelty, mean that currently a lot of diagnostic and therapeutic tools, established and tentative alike, are needed to treat patients in a timely, effective way. In order to make these tools more reliable, faster and more feasible, biological fluid microsampling techniques could provide many advantages. In this review, the most important microsampling techniques are considered (dried matrix spots, volumetric absorptive microsampling, microfluidics and capillary microsampling, solid phase microextraction) and their respective advantages and disadvantages laid out. Moreover, currently available microsampling applications of interest for SARS-CoV-2 therapy are described, in order to make them as much widely known as possible, hopefully providing useful information to researchers and clinicians alike.


Asunto(s)
Técnicas de Química Analítica/tendencias , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Recolección de Muestras de Sangre , COVID-19 , Infecciones por Coronavirus/terapia , Pruebas con Sangre Seca , Humanos , Pandemias , Neumonía Viral/terapia , Microextracción en Fase Sólida , Espectrometría de Masas en Tándem
8.
Sheng Wu Gong Cheng Xue Bao ; 36(7): 1261-1268, 2020 Jul 25.
Artículo en Chino | MEDLINE | ID: mdl-32748583

RESUMEN

The phenomenon of phase separation of intracellular biological macromolecules is an emerging research field that has received great attention in recent years. As an aggregation and compartment mechanism of cell biochemical reactions, it widely exists in nature and participates in important physiological processes such as gene transcription and regulation, as well as influences organism's response to external stimuli. Disequilibrium of phase separation may lead to the occurrence of some major diseases. Researchers in cross-cutting fields are trying to examine dementia and other related diseases from a new perspective of phase separation, exploring its molecular mechanism and the potential possibility of intervention and treatment. This review intends to introduce the latest research progress in this field, summarize the major research directions, biochemical basis, its relationship with disease occurrence, and giving a future perspective of key problems to focus on.


Asunto(s)
Citoplasma , Sustancias Macromoleculares , Investigación , Animales , Técnicas de Química Analítica/tendencias , Citoplasma/química , Citoplasma/metabolismo , Humanos , Sustancias Macromoleculares/aislamiento & purificación , Investigación/tendencias
9.
Molecules ; 25(16)2020 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-32764423

RESUMEN

Modern analytical chemistry plays a vital role in pharmaceutical sciences [...].


Asunto(s)
Técnicas de Química Analítica/tendencias , Química Farmacéutica/tendencias , Diseño de Fármacos , Descubrimiento de Drogas , Preparaciones Farmacéuticas , Humanos
10.
Biotechnol J ; 15(8): e1900274, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32333634

RESUMEN

While packed bed chromatography, known as conventional chromatography, has been serving the biopharmaceutical industry for decades as the bioseparation method of choice, alternative approaches are likely to take an increasing leading role in the next few years. The high number of new biological drugs under development, and the need to make biopharmaceuticals widely accessible, has been driving the academia and industry in the quest of anything but conventional chromatography approaches. In this perspective paper, these alternative approaches are discussed in view of current and future challenges in the downstream processing field.


Asunto(s)
Técnicas de Química Analítica , Técnicas de Química Analítica/métodos , Técnicas de Química Analítica/tendencias , Química Farmacéutica/métodos , Química Farmacéutica/tendencias , Cromatografía
11.
Anal Chim Acta ; 1083: 19-40, 2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31493808

RESUMEN

Several analytical approaches have been developed for the determination of emerging pollutants (EPs), including pharmaceuticals and personal care products (PPCPs) in environmental matrices. This paper reviews the sample preparation and instrumental methods proposed in the last few years (2012-2018) to assess PPCPs in sewage sludge. Three main steps are examined: extraction, clean-up and analysis. Sample preparation is critical as target compounds are normally found at low concentrations in complex matrices. Most procedures include sewage sludge pretreatment mostly through ultrasound-assisted extraction (UAE) although other novel techniques such as QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) or MSPD (matrix solid-phase dispersion) have been also employed. In one report, no differences in extraction efficiency were detected among the most commonly used extraction techniques such as ultrasound, microwave and pressurized liquid. Clean-up usually involves a conventional method such as solid phase extraction (SPE). This step is needed to appreciably reduce matrix suppression, and is followed by an instrumental analysis using techniques of preference such as gas chromatography (GC) or liquid chromatography (LC), mostly coupled to mass spectrometry (MS). A fully automated on-line system that includes extraction, chromatographic separation, and mass spectrometry in one-stage is here presented as a novel way of determining PPCPs in sewage sludge. This review also discusses the advantages and limitations of the different techniques used. Miniaturizing analytical techniques and the use of novel solid and liquid phase materials are emerging as efficient options that fulfill the principles of so-called "green chemistry".


Asunto(s)
Técnicas de Química Analítica/métodos , Cosméticos/análisis , Preparaciones Farmacéuticas/análisis , Aguas del Alcantarillado/análisis , Contaminantes Químicos del Agua/análisis , Fraccionamiento Químico/métodos , Técnicas de Química Analítica/tendencias
13.
Chem Rev ; 119(13): 7996-8027, 2019 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-31070892

RESUMEN

The Internet of Things (IoT) is a megatrend that cuts across all scientific and engineering disciplines and establishes an integrating technical evolution to improve production efficiencies and daily human life. Linked machines and sensors use decision-making routines to work toward a common product or solution. Expanding this technical revolution into the value chain of complex areas such as agriculture, food production, and healthcare requires the implementation and connection of sophisticated (bio)analytical methods. Today, wearable sensors, monitors, and point-of-care diagnostic tests are part of our daily lives and improve patients' medical progression or athletes' monitoring capabilities that are already beyond imagination. Also, early contributions toward sensor networks and finally the IT revolution with wireless data collection and transmission via Bluetooth or smartphones have set the foundation to connect remote sensors and distributed analytical chemical services with centralized laboratories, cloud storage, and cloud computing. Here, we critically review those biosensor and chemosensor technologies and concepts used in an IoT setting or considered IoT-ready that were published in the period 2013-2018, while also pointing to those foundational concepts and ideas that arose over the last two decades. We focus on these sensors due to their unique ability to be remotely stationed and that easily function in networks and have made the greatest progress toward IoT integration. Finally, we highlight requirements and existing and future challenges and provide possible solutions important toward the vision of a seamless integration into a global analytical concept, which includes many more analytical techniques than sensors and includes foremost next-generation sequencing and separation principles coupled with MS detection.


Asunto(s)
Técnicas Biosensibles/tendencias , Técnicas de Química Analítica/tendencias , Internet de las Cosas/tendencias , Animales , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Técnicas de Química Analítica/instrumentación , Técnicas de Química Analítica/métodos , Humanos , Sistemas de Atención de Punto/tendencias
14.
J Chromatogr A ; 1606: 360245, 2019 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-31122728

RESUMEN

In this review, recent advances in the analysis of water-soluble vitamins (WSVs) have been reported considering the advantages and disadvantages of various extraction, separation and detection techniques, commonly used for their quantification. Acid hydrolysis, enzyme treatment, SPE based methods and some other extraction methods have been discussed. Particular attention has been devoted to the analytical techniques based on liquid chromatography and electrophoresis. Furthermore, suitability and selectivity of hydrophilic interaction liquid chromatography (HILIC) for WSVs has been discussed in detail. Problems related to these techniques and their possible solutions have also been considered. Special focus has been given to the applications of liquid chromatography (since 2014-2019) for the simultaneous analysis of WSVs and their homologous in complex food samples.


Asunto(s)
Técnicas de Química Analítica/métodos , Técnicas de Química Analítica/tendencias , Vitaminas/análisis , Agua/química , Electroforesis Capilar , Interacciones Hidrofóbicas e Hidrofílicas , Solubilidad , Vitaminas/química
15.
An Acad Bras Cienc ; 91(suppl 1): e20180294, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31017188

RESUMEN

Green Analytical Chemistry (GAC) is a research field that seeks for more sustainable analytical approaches to minimize the toxicity and amounts of wastes without hindering the analytical performance. This is a trend in Analytical Chemistry worldwide and because of the diversity of innovations on this subject, Brazil stands out as the third in the list of the main contributors to GAC, with ca. 11.2% of the published articles. Significant innovations and interesting applications in several fields have been presented and Brazil is continuously moving from Chemistry to Green Chemistry also in the Analytical Chemistry field. Selected contributions for sample preparation, spectro- and electroanalysis, separation techniques, chemometrics, and also procedures for point-of-care measurements are critically reviewed.


Asunto(s)
Técnicas de Química Analítica/tendencias , Tecnología Química Verde/tendencias , Investigación/tendencias , Brasil , Técnicas de Química Analítica/métodos , Tecnología Química Verde/métodos , Humanos , Microextracción en Fase Líquida/métodos , Microextracción en Fase Líquida/tendencias , Microextracción en Fase Sólida/métodos , Microextracción en Fase Sólida/tendencias , Solventes , Análisis Espectral/métodos , Análisis Espectral/tendencias
17.
J Ethnopharmacol ; 236: 443-465, 2019 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-30802611

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Panax notoginseng (Burk.) F. H. Chen, also called Sanqi, is a widely used traditional Chinese medicine, which has long history used as herbal medicines. It is currently an important medicinal material in China, holding the first place in the sale volume of the whole patent medicines market in China, and the market size of the single species has exceeded 10 billion yuan. In addition, P. notoginseng is an important constituent part of many famous Chinese patent medicines, such as Compound Danshen Dripping Pills and Yunnan Baiyao. P. notoginseng saponins (PNSs), which are the major active components of P. notoginseng, are a kind of chemical mixture containing different dammarane-type saponins. Many studies show that PNSs have been extensively used in medical research or applications, such as atherosclerosis, diabetes, acute lung injury, cancer, and cardiovascular diseases. In addition, various PNS preparations, such as injections and capsules, have been made commercially available and are widely applied in clinical practice. AIM OF THE REVIEW: Since the safety and efficacy of compounds are related to their qualitative and quantitative analyses, this review briefly summarizes the analytic approaches for PNSs and their biological effects developed in the last decade. METHODOLOGY: This review conducted a systematic search in electronic databases, such as Pubmed, Google Scholar, SciFinder, ISI Web of Science, and CNKI, since 2009. The information provided in this review is based on peer-reviewed papers and patents in either English or Chinese. RESULTS: At present, the chromatographic technique remains the most extensively used approach for the identification or quantitation of PNSs, coupled with different detectors, among which the difference mainly lies in their sensitivity and specificity for analyzing various compounds. It is well-known that PNSs have traditionally strong activity on cardiovascular diseases, such as atherosclerosis, intracerebral hemorrhage, or brain injury. The recent studies showed that PNSs also responded to osteoporosis, cancers, diabetes, and drug toxicity. However, some other studies also showed that some PNSs injections and special PNS components might lead to some biological toxicity under certain dosages. CONCLUSION: This review may be used as a basis for further research in the field of quantitative and qualitative analyses, and is expected to provide updated and valuable insights into the potential medicinal applications of PNSs.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Panax notoginseng/química , Control de Calidad , Saponinas/farmacología , Técnicas de Química Analítica/métodos , Técnicas de Química Analítica/tendencias , Química Farmacéutica/métodos , Química Farmacéutica/tendencias , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/normas , Medicina Tradicional China , Saponinas/análisis , Saponinas/normas
18.
J Chromatogr A ; 1587: 2-13, 2019 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-30651205

RESUMEN

This review discusses recent advances in both theory and experiment regarding multi-way chromatographic calibration. The focus is directed towards the chemometric processing of multi-way data arrays in which one or more instrumental modes describe the elution time behavior across liquid or gas chromatographic columns, and the remaining ones are of spectroscopic nature, e.g. UV-vis absorption, fluorescence emission (either as vectors or matrices) or mass spectrometry. Successful multi-way data decomposition into profiles for the contributing components allows one to perform quantitative analysis of complex samples. Quantitative applications usually make appropriate use of the second-order advantage which is inherent to multi-way data processing, and reduce the complexity of the data to a virtual univariate calibration which is typical of classical analytical chemistry. A number of recent experimental works will be discussed to illustrate the above concepts.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/tendencias , Calibración , Técnicas de Química Analítica/tendencias , Cromatografía de Gases y Espectrometría de Masas/normas
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