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1.
J Chromatogr A ; 1716: 464653, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38232638

RESUMO

The comprehensive study of compound variations in released smoke during the combustion process is a great challenge in many scientific fields related to analytical chemistry like traditional Chinese medicine, environment analysis, food analysis, etc. In this work, we propose a new comprehensive strategy for efficiently and high-thoroughly characterizing compounds in the online released complex smokes: (i) A smoke capture device was designed for efficiently collecting chemical constituents to perform gas chromatography-mass spectrometry (GC-MS) based untargeted analysis. (ii) An advanced data analysis tool, AntDAS-GCMS, was used for automatically extracting compounds in the original acquired GC-MS data files. Additionally, a GC-MS data analysis guided instrumental parameter optimizing strategy was proposed for the optimization of parameters in the smoke capture device. The developed strategy was demonstrated by the study of compound variations in the smoke of traditional Chinese medicine, Artemisia argyi Levl. et Vant. The results indicated that more than 590 components showed significant differences among released smokes of various moxa velvet ratios. Finally, about 88 compounds were identified, of which phenolic compounds were the most abundant, followed by aromatics, alkenes, alcohols and furans. In conclusion, we may provide a novel approach to the studies of compounds in online released smoke.


Assuntos
Artemisia , Artemisia/química , Medicina Tradicional Chinesa , Fumaça , Cromatografia Gasosa-Espectrometria de Massas/métodos
2.
Electrophoresis ; 39(17): 2218-2227, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29869395

RESUMO

A rapid, simple, and efficient sample extraction method based on micro-matrix-solid-phase dispersion (micro-MSPD) was applied to the extraction of polyphenols from pomegranate peel. Five target analytes were determined by ultra-HPLC coupled with Q-TOF/MS. Carbon molecular sieve (CMS) was firstly used as dispersant to improve extraction efficiency in micro-MSPD. The major micro-MSPD parameters, such as type of dispersant, amount of dispersant, grinding time, and the type and the volume of elution solvents, were studied and optimized. Under optimized conditions, 26 mg of pomegranate peel was dispersed with 32.5 mg of CMS, the grinding time was selected as 90 s, the dispersed sample was eluted with 100 µL of methanol. Results showed that the proposed method was of good linearity for concentrations of analytes against their peak areas (coefficient of determination r2 > 0.990), the LOD was as low as 3.2 ng/mL, and the spiking recoveries were between 88.1 and 106%. Satisfactory results were obtained for the extraction of gallic acid, punicalagin A, punicalagin B, catechin, and ellagic acid from pomegranate peel sample, which demonstrated nice reliability and high sensitivity of this approach.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Lythraceae/química , Espectrometria de Massas/métodos , Polifenóis/isolamento & purificação , Extração em Fase Sólida/métodos , Carbono/química , Limite de Detecção , Modelos Lineares , Extratos Vegetais/química , Polifenóis/análise , Polifenóis/química , Reprodutibilidade dos Testes
3.
J Chromatogr A ; 1509: 50-59, 2017 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-28645755

RESUMO

Zwitterionic surfactant, used as extractant in microwave-assisted extraction (MAE) was investigated for the first time to extract organic and inorganic iodines from kelp samples. Optimized conditions for the MAE were 200W of microwave irradiation power, 100°C of extraction temperature, 10min of microwave irradiation time, 1g of sample, and 20mL of solvent volume. Ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) was used for the quantitative and qualitative analyses of the iodines. Under the optimum experimental conditions, KI, MIT and DIT were identified in kelp samples, the limits of detection of these analytes were ranged between 3.39 and 6.31ng/mL. The recoveries for spiked samples obtained from different areas were all higher than 92.48%. Compared with the ultrasound-assisted extraction, the proposed method is faster and more effective. Thus, the combination of zwitterionic surfactant-MAE and UHPLC-Q-TOF/MS made up a simple, rapid and effective approach for extraction and determination of iodine compounds in complex seaweed materials.


Assuntos
Fracionamento Químico/métodos , Iodo/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Alga Marinha/química , Tensoativos/química , Verduras/química , Fracionamento Químico/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Iodo/química , Espectrometria de Massas/métodos , Micelas , Micro-Ondas , Extratos Vegetais/química
4.
J Chromatogr A ; 1499: 132-139, 2017 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-28390669

RESUMO

An environmentally friendly ionic liquid-in-water (IL/W) microemulsion was established and applied as mobile phase in microemulsion liquid chromatography (MELC) with ultraviolet (UV) detection or electrochemical detector (ECD) for analysis of phenolic compounds in real samples. The optimal condition of the method was using the best composition of microemulsion (0.2% w/v [HMIM]PF6, 1.0% w/v SDS, 3.0% w/v n-butanol, 95.8% v/v water, pH 2.5) with UV detection. The validation results indicated that the method provided high degree of sensitivity, precision and accuracy with the low limit of detections ranged from 17.9-238ng/mL, satisfactory mean recovery values in the range of 80.1-105% and good linearity (r2>0.9994). Additionally, this method exhibited high selectivity and resolution for the analytes and was more eco-friendly compared with traditional MELC method. Consequently, the established IL/W MELC method was successfully applied to simultaneously separate and determine target compounds in Danshen sample and its preparation.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Hidroxibenzoatos/análise , Líquidos Iônicos/química , Salvia miltiorrhiza/química , Cromatografia Líquida de Alta Pressão/instrumentação , Eletroquímica/instrumentação , Eletroquímica/métodos , Emulsões/química , Fenantrolinas/análise , Espectrofotometria Ultravioleta/instrumentação , Espectrofotometria Ultravioleta/métodos , Água/química
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