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1.
J Chromatogr A ; 1727: 464990, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38744188

RESUMEN

An approach for the controllable separation and concentration of nucleic acid using a circular nonuniform electric field was proposed and developed. Using six different lengths of DNA molecules as standard samples, the distribution of the gradient electric field was increased from the outer circular electrode to the inner rod-shaped electrode, contributing to the migration of DNA molecules at a velocity gradient towards the region with the strongest inner electric field. The DNA molecules were arranged in a distribution of concentric circles that aligned with the distribution of concentric equipotential lines. The concentration of DNA multiplied with the alternation of radius. As a result, this platform allowed simultaneous DNA separation, achieving a resolution range of 1.17-3.03 through an extended electrophoresis time, resulting in enhanced concentration factors of 1.08-6.27. Moreover, the manipulation of the relative height of the inner and outer electrodes enabled precise control over the distribution and the deflection degree of electric field lines, leading to accurate control over DNA deflection.


Asunto(s)
ADN , ADN/aislamiento & purificación , ADN/análisis , ADN/química , Electrodos , Electricidad , Electroforesis Capilar/métodos
2.
Anal Chim Acta ; 1295: 342288, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38355222

RESUMEN

BACKGROUND: Vitamins are micronutrients that are required for normal growth and development of living organisms. However, due to their various chemical properties (e.g., acid-base behavior, the presence of numerous forms) and fluctuating concentration levels within complex matrices, simultaneous analysis of multi-class vitamins, including their active forms, is a challenging task. The growing nutrient shortage in foods is concerning for food consumers, manufacturers, and quality control organizations. Hence, a simple, fast, and greener approach that can simultaneously analyze multi-class vitamins is required to aid food testing and clinical laboratories in evaluating vitamin content more rapidly and accurately. RESULTS: A green and rapid analytical method based on online two-dimensional microscale carbon fiber/activated carbon fiber fractionation-mass spectrometry (2DµCFs-MS) was developed and validated for simultaneous determination of vitamins (water- and fat-soluble vitamins and some analogs) in food supplements and fortified energy drinks. Vitamins have been successfully separated into three different fractions using the minimum toxic solvent (only 0.7 mL of organic solvent) in a single run within 6 min. The limit of detection (LOD) ranges from 0.1 to 10.4 ng/mL, and the limit of quantification (LOQ) ranges from 0.39 to 34.5 ng/mL. The method also showed adequate repeatability and intermediate precision, with RSD<10 % and R2 > 0.99 for most vitamins. The analytical method was evaluated in terms of greenness, with an analytical greenness (AGREE) score of 0.68. SIGNIFICANCE: The 2DµCFs-MS system was developed to separate and detect multi-class vitamins simultaneously, which can be used as a beneficial tool to investigate vitamin content for food labeling and determining the vitamins in biological fluids and other complex samples. The developed method can tackle the challenge of simultaneous and fast routine analysis of multi-class vitamins.


Asunto(s)
Vitaminas , Agua , Agua/química , Vitaminas/análisis , Vitaminas/química , Suplementos Dietéticos/análisis , Nutrientes , Solventes/análisis
3.
J Chromatogr A ; 1719: 464774, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38422707

RESUMEN

Ginseng is beneficial in the prevention of many diseases and provides benefits for proper growth and development owing to the presence of various useful bioactive substances of diverse chemical heterogeneity (e.g., triterpenoid saponins, polysaccharides, volatile oils, and amino acids). As a result, understanding the therapeutic advantages of ginseng requires an in-depth compositional evaluation employing a simple and rapid analytical technique. In this work, three types of surface-activated carbon fibers (ACFs) were prepared by gas-phase oxidation, strong acid treatment, and Plasma treatment to obtain CO2-ACFs, acidified-ACFs, and plasma-ACFs, respectively. Three prepared ACFs were compared in terms of their physicochemical characterization (i.e., surface roughness and functional groups). A separation system was built using a column with modified ACFs, followed by mass spectrometry detection to investigate and determine substances of different polarities. Among the three columns, CO2-ACFs showed the optimum separation effect. 13 strong polar compounds (12 amino acids and1 oligosaccharide) and 15 lesser polar compounds (ginsenosides) were separated and identified successfully within 4 min in the ginseng sample. The data obtained by CO2-ACFs-TOF-MS/MS and UHPLC-TOF-MS/MS were compared. Our approach was found to be faster (4 min vs. 36 min) and greener, requiring much less solvent (1 mL vs. 10.8 mL), and power (0.06 vs. 0.6 kWh). The developed methodology can provide a faster, eco-friendly, and more reliable tool for the high-throughput screening of complex natural matrices and the simultaneous evaluation of several compounds in diverse samples.


Asunto(s)
Ginsenósidos , Panax , Ginsenósidos/análisis , Espectrometría de Masas en Tándem/métodos , Carbón Orgánico , Fibra de Carbono , Dióxido de Carbono/análisis , Extractos Vegetales/química , Aminoácidos , Panax/química , Cromatografía Líquida de Alta Presión/métodos
4.
Anal Chim Acta ; 1287: 342110, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38182347

RESUMEN

BACKGROUND: Liposomal formulations have traditionally been considered the most therapeutically effective drug delivery systems (DDS). However, their pharmacokinetics study and efficacy assessment are still challenging given size heterogeneity and unknown forms in vivo. The pharmacodynamic evaluation that solely analyzes total drug concentration is unfit for the liposomal formulation study. Hence, it is crucial to develop effective strategies for the separation and analysis of different forms of liposomal formulations in order to contribute to the study of pharmacokinetic profiles associated with both liposome-incorporated and non-liposomal drugs. (84) RESULTS: A laboratory-built circular nonuniform electric field gel electrophoresis (CNEFGE) system was developed in this study for simultaneous separation and analysis of various forms of doxorubicin hydrochloride (DOX•HCl) liposomes. Liposomes were effectively fractionized based on their size and higher concentration in situ in the concentration zone, obtaining liposome recovery >95 % and a 3.04 concentration factor. It was found that the technique could be used to evaluate not only the size distribution of liposomes but also the drug loading capacity related to size. The charge-to-size-based separation mechanism has also allowed the simultaneous separation of liposome-entrapped drugs, protein-bound drugs, and free drugs in various forms, and the technique has been successfully employed in serum. Moreover, the quantification analysis of liposomes incubated with serum for 72 h showed that the proportion of the ratio of DOX•HCl in liposome-entrapped drugs, protein-bound drugs, and free drugs is approximately 97:2:1. (143) SIGNIFICANCE: Using the separation principle of gel electrophoresis and the electrification characteristics of drug carriers, this study developed and implemented an efficient approach for the simultaneous separation and concentration of multiple forms of drug liposomes in vivo. This approach offers a wide range of applications in the pharmacokinetics, efficacy, and safety evaluation of drug carriers and liposomes. (56).


Asunto(s)
Portadores de Fármacos , Liposomas , Sistemas de Liberación de Medicamentos , Doxorrubicina , Electroforesis
5.
Anal Chim Acta ; 1283: 341907, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37977798

RESUMEN

BACKGROUND: As a vital energy source, light is one of the most significant environmental signals for plants' growth and development. The crosstalk amongst phytohormones regulated by light exhibits quantitative dynamic changes, but methodologies to analyze their distribution during plant growth are still limited. Rapid, highly sensitive, low-invasive detection and simultaneous assessment of the levels of multiple classes of phytohormones have important phytology applications, however the existing sample pretreatment strategies remain intricate, laborious, and far from being developed for in vivo high-sensitivity testing. (81) RESULTS: We applied a nanoconfined liquid phase nanoextraction (NLPNE) technique based on acidified carbon nanofibers (ACNFs) in combination with LC-ESI-MS/MS for highly sensitive analysis of acidic phytohormones' photoregulation and dynamic distribution. In this system, the mass transfer ability of analytes entering the nanoconfined space is significantly improved given the nanoconfined effect. In particular, the accelerated and strong adsorption of alkaline compounds to the ACNFs surface provide minimum interference for acidic compounds (photosensitive phytohormones), which facilitates their simple, fast, and selective quantification with improved sensitivity. The ACNFs-NLPNE strategy achieved quantitative enrichment of multi-class phytohormones in less than 5 min, and detection limits down to 0.49 fg mL-1. Moreover, we monitored the phytohormone changes under red and blue monochromatic light with relative standard deviations <13.4 %. The results further indicated that short-time red light regulation promoted Lepidium sativum L. growth while blue light inhibited it. (141) SIGNIFICANCE: A nanoconfinement effect-based sample pretreatment platform was developed for monitoring photoregulation phytohormones dynamic distribution with higher sensitivity and stability. Our findings highlighted the importance of the NLPNE approach in providing an accurate plant crosstalk information at the molecular level, which opens a promising avenue for investigating internal hormonal responses to external stimuli. (52).


Asunto(s)
Reguladores del Crecimiento de las Plantas , Espectrometría de Masas en Tándem , Reguladores del Crecimiento de las Plantas/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía Liquida/métodos , Plantas , Luz , Ácidos , Cromatografía Líquida de Alta Presión/métodos
6.
Environ Sci Pollut Res Int ; 29(5): 7079-7088, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34467484

RESUMEN

Due to their wide distribution and availability, plant leaves can be considered interesting candidates as biomonitoring substrates for the evaluation of atmospheric pollution. In addition, some species can also retain historical information, for example, related to environmental pollution, due to their leaf class age. In this study, the content of polycyclic aromatic hydrocarbons (PAHs) in Abies holophylla and Pinus tabuliformis needle samples in the function of their class age has been investigated to obtain information regarding the degradation constant for each PAH under investigation (α values ranging from 0.173 to 1.870) and to evaluate the possibility to correlate the presence of PAHs in needles with some important pollution environmental factors. Considering air pollutant variables registered in Jilin Province, interesting correlations (at 95% confidence level) have been found between coal consumption per year and anthracene contents in needles, while fluorene, phenanthrene, and anthracene results correlated with coal consumption. Furthermore, it has been demonstrated that the total PAH concentration in needles, for both species, increased with their age (from 804 to 3604 ng g-1 dry weight), showing a general tendency to accumulate these substances through years. PAH degradation rates increased instead with molecular complexity. This study could be considered a first trial to obtain historical environmental information by pine needles biomonitoring.


Asunto(s)
Abies , Pinus , Hidrocarburos Policíclicos Aromáticos , China , Monitoreo del Ambiente , Hojas de la Planta/química , Hidrocarburos Policíclicos Aromáticos/análisis
7.
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
8.
J Comb Chem ; 6(1): 126-34, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-14714996

RESUMEN

A general methodology has been established for rapid generation and screening of combinatorial glycopeptide library and subsequent mass spectrometric sequencing to identify the mimetics of Galalpha(1,3)Gal epitopes. Using this approach, several active glycopeptide sequences were recognized and found to inhibit the binding of human natural anti-Gal antibodies with comparable IC(50)s to synthetic Galalpha(1,3)Gal oligosaccharides. The most active glycopeptides detected from the library included Gal-Tyr-Trp-Arg-Tyr, Gal-Thr-Trp-Arg-Tyr, and Gal-Arg-Trp-Arg-Tyr. These glycopeptides showed higher affinities to anti-Gal antibodies than known Galalpha(1,3)Gal peptide mimetics, such as DAHWESWL and SSLRGF. Our results suggest that, by combining a peptide sequence (the "functional" mimic part) with a terminal alpha-linked galactose moiety (the "structural" mimic part), the resulting glycopeptide could be a very good Galalpha(1,3)Gal mimetic. Analysis of these active glycopeptides provided first-hand information regarding the binding site of anti-Gal antibodies to facilitate the structurally based design of more potent and stable inhibitors.


Asunto(s)
Epítopos/química , Galactosa/química , Glicopéptidos/síntesis química , Animales , Secuencia de Carbohidratos , Técnicas Químicas Combinatorias , Cristalografía por Rayos X , Ensayo de Inmunoadsorción Enzimática , Glicopéptidos/química , Humanos , Inmunoglobulina A/química , Inmunoglobulina G/química , Inmunoglobulina M/química , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Oligosacáridos/química , Biblioteca de Péptidos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
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