Determination of enterostatin in human cerebrospinal fluid by capillary electrophoresis with laser induced fluorescence detection.
A capillary electrophoresis (CE) method with laser induced fluorescence (LIF) detection is described for quantification of enterostatin (Val-Pro-Asp-Pro-Arg), a pentapeptide involved in appetite regulation and insulin secretion. Enterostatin and two other pentapeptides belonging to the enterostatin family (i.e. Ala-Pro-Gly-Pro-Arg and Val-Pro-Gly-Pro-Arg) were well separated from each other. The peptides were fluorescently tagged with naphthalene-2,3- dicarboxaldehyde (NDA) and separated by micellar electrokinetic chromatography (MEKC) in the presence of methanol as an organic modifier. Coupled with LIF detection, the method had a detection limit of 4.8 x 10(-6) M for enterostatin. The relative standard deviation was to be 4.0% from five determinations of enterostatin at 37.2 microM in a human cerebrospinal fluid (CSF) sample. Twenty-three human CSF samples were analyzed. The level of enterostatin ranged from 24 microM to 51 microM with a mean (+/- SEM) value of 41.7 +/- 2.0 microM.
Zhao
S
S
Department of Chemistry, Jackson State University, MS 39217, USA.
Prasad
C
C
Robertson
H J
HJ
Liu
Y M
YM
D000595:Amino Acid Sequence; D002845:Chromatography / Q000379:methods; D003089:Colipases / Q000134:cerebrospinal fluid* / Q000302:isolation & purification; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods; D004792:Enzyme Precursors; D006801:Humans; D007202:Indicators and Reagents; D008823:Micelles; D009281:Naphthalenes; D009842:Oligopeptides / Q000737:chemistry / Q000302:isolation & purification; D011498:Protein Precursors / Q000134:cerebrospinal fluid* / Q000302:isolation & purification; D013050:Spectrometry, Fluorescence / Q000379:methods
D003089:Colipases; D004792:Enzyme Precursors; D007202:Indicators and Reagents; D008823:Micelles; D009281:Naphthalenes; D009842:Oligopeptides; D011498:Protein Precursors; C027717:2,3-naphthalenedicarboxaldehyde; C037107:procolipase