Premium
Transient isotachophoresis in on‐line solid phase extraction capillary electrophoresis time‐of‐flight‐mass spectrometry for peptide analysis in human plasma
Author(s) -
MedinaCasanellas Silvia,
Benavente Fernando,
Barbosa José,
SanzNebot Victoria
Publication year - 2011
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.201100017
Subject(s) - chromatography , isotachophoresis , capillary electrophoresis , chemistry , repeatability , mass spectrometry , time of flight mass spectrometry , detection limit , solid phase extraction , extraction (chemistry) , analytical chemistry (journal) , electrolyte , ion , organic chemistry , electrode , ionization
In this study, we evaluated the combination of transient isotachophoresis with on‐line solid‐phase extraction capillary electrophoresis time‐of‐flight mass spectrometry (SPE‐tITP‐CE‐TOF‐MS) to improve sensitivity of peptide analysis, using several opioid peptides as model compounds. First, standard solutions were analyzed in order to establish the tITP‐CE methodology using UV and TOF‐MS detection. The volume and composition of the leading and terminating electrolytes (i.e. LE and TE) for an efficient tITP were investigated to obtain optimum detection sensitivity and electrophoretic separation. In the best cases, LODs in tITP‐CE‐TOF‐MS were tenfold better than those obtained in CE‐TOF‐MS (i.e. 5 versus 50 ng/mL). Afterwards, the tITP‐CE‐TOF‐MS methodology was adapted to perform SPE‐tITP‐CE‐TOF‐MS. Repeatability, linearity and LODs were investigated and compared to the values obtained by SPE‐CE‐TOF‐MS. Furthermore, human plasma samples fortified with the opioid peptides were analyzed in order to show the potential of SPE‐tITP‐CE‐TOF‐MS for peptide analysis in biological fluids. The LODs attained in standard solutions and plasma samples for some of the studied peptides (i.e. 0.01 and 0.1 ng/mL, respectively) were tenfold better than those obtained in SPE‐CE‐TOF‐MS, proving the enhanced sensitivity that could be achieved when both on‐line preconcentration approaches were combined together.