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1.
J Sep Sci ; 39(14): 2678-88, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27229265

RESUMO

Iron nanoparticles were prepared by a green method following functionalization using 1-butyl-3-methylimidazolium bromide. 1-Butyl-3-methylimidazole iron nanoparticles were characterized using FTIR spectroscopy, energy dispersive X-ray fluorescence, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The nanoparticles were used in solid-phase membrane micro-tip extraction to separate vitamin B complex from plasma before high-performance liquid chromatography. The optimum conditions obtained were sorbent (15 mg), agitation time (30 min), pH (9.0), desorbing solvent [water (5 mL) + methanol (5 mL) + sodium hydroxide (0.1 N) + acetic acid (d = 1.05 kg/L, pH 5.5), desorbing volume (10 mL) and desorption time (30 min). The percentage recoveries of all the eight vitamin B complex were from 60 to 83%. A high-performance liquid chromatography method was developed using a PhE column (250 × 4.6 mm, 5.0 µm) and water/acetonitrile (95:5, v/v; pH 4.0 with 0.1% formic acid) mobile phase. The flow rate was 1.0 mL/min with detection at 270 and 210 nm. The values of the capacity, separation and resolution factor were 0.57-39.47, 1.12-6.00 and 1.84-26.26, respectively. The developed sample preparation and chromatographic methods were fast, selective, inexpensive, economic and reproducible. The developed method can be applied for analyzing these drugs in biological and environmental matrices.


Assuntos
Ferro/química , Nanopartículas Metálicas/química , Microextração em Fase Sólida , Complexo Vitamínico B/sangue , Cromatografia Líquida de Alta Pressão , Humanos
2.
J Chromatogr Sci ; 51(8): 807-18, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23619556

RESUMO

ß-Adrenergic blockers represent a very important class of drugs that are used worldwide for treating various cardiac diseases. The present article describes the state-of-the art of analyses of ß-adrenergic blockers using high-performance liquid chromatography (HPLC). Sample preparation techniques such as liquid-liquid extraction, solid-phase extraction and solid-phase microextraction have been discussed, which are essential prior to HPLC analysis. Additionally, applications of liquid chromatography coupled with tandem mass spectrometry are included. HPLC methods have been reported to include 0.6-26 min as the run times and 0.01 ng/mL to 25 µg/mL as detection limits. The most commonly used columns were C18 with various buffers as the mobile phases, along with various organic modifiers. The optimization of HPLC conditions has been discussed. It has been observed that the reported methods are quite satisfactory for the analyses of ß-adrenergic blockers in biological samples. Future perspectives in the hyphenation of solid-phase microextraction-nano-liquid chromatography-tandem mass spectrometry have also been highlighted to achieve detections at nanogram and picogram levels. The present article is very useful for academicians, scientists, drug and pharmaceutical personnel and government regulatory authorities.


Assuntos
Antagonistas Adrenérgicos beta/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Antagonistas Adrenérgicos beta/sangue , Antagonistas Adrenérgicos beta/química , Antagonistas Adrenérgicos beta/urina , Humanos , Limite de Detecção , Extração Líquido-Líquido , Reprodutibilidade dos Testes , Extração em Fase Sólida
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