Document Detail


Positively charged sol-gel coatings for on-line preconcentration of amino acids in capillary electrophoresis.
MedLine Citation:
PMID:  14697054     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
A novel on-line method is presented for the extraction and preconcentration of amino acids using a sol-gel-coated column coupled to a conventional UV/visible detector. The presented approach does not require any additional modification of the commercially available standard CE instrument. Extraction, stacking, and focusing techniques were used in the preconcentration procedures. Sol-gel coatings were created by using N-octadecyldimethyl[3-(trimethoxysilyl)propyl]ammonium chloride (C18-TMS) in the coating sol solutions. Due to the presence of a positively charged quaternary ammonium moiety in C18-TMS, the resulting sol-gel coating carried a positive charge. For extraction, the pH of the samples was properly adjusted to impart a net negative charge to amino acids. A long plug of the sample was then passed through the sol-gel-coated capillary to facilitate extraction via electrostatic interaction between the positively charged sol-gel coating and the negatively charged amino acid molecules. Focusing of the extracted amino acids was accomplished through desorption of the extracted amino acid molecules carried out by local pH change. Two different methods are described. Both methods showed excellent extraction and preconcentration effects. Preconcentration results obtained on sol-gel-coated columns were compared with the CZE analysis performed on bare fused-silica columns with traditional sample injections. The described procedure provided a 150,000-fold enrichment effect for alanine. The two methods provided acceptable repeatability in terms of both peak height and migration time.
Authors:
Wen Li; David Fries; Abdel Alli; Abdul Malik
Related Documents :
16345704 - Purification and some properties of diplococcin from streptococcus cremoris 346.
14342224 - Amino acid composition and c-terminal residues of algal biliproteins.
6852354 - Evidence for a biologically active, carrier-bound form of non-suppressible insulin-like...
8281264 - Effect of urea concentration on the base-specific separation of oligodeoxynucleotides i...
9599954 - An experimental study on evaluation of chemical antagonists induced snake venom neutral...
977214 - Effects of l-lysine administration on certain aspects of ascorbic acid metabolism.
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  Analytical chemistry     Volume:  76     ISSN:  0003-2700     ISO Abbreviation:  Anal. Chem.     Publication Date:  2004 Jan 
Date Detail:
Created Date:  2003-12-30     Completed Date:  2004-10-25     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0370536     Medline TA:  Anal Chem     Country:  United States    
Other Details:
Languages:  eng     Pagination:  218-27     Citation Subset:  IM    
Affiliation:
Department of Chemistry, University of South Florida, 4202 East Fowler Avenue, Tampa, Florida 33620, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Amino Acids / analysis*,  chemistry
Electrochemistry
Electrophoresis, Capillary / methods
Phase Transition*
Chemical
Reg. No./Substance:
0/Amino Acids

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  The nature of phosphorylated chrysin-protein interactions involved in noncovalent complex formation ...
Next Document:  Two-step liquid-liquid-liquid microextraction of nonsteroidal antiinflammatory drugs in wastewater.