Capillary electrochromatography/nanoelectrospray mass spectrometry for attomole characterization of peptides.
The successful coupling of capillary electrochromatography (CEC) to an ion trap mass spectrometer via a nanoelectrospray interface (nESI) is described. Using a conductively coated tip butted to the end of a CEC column, it was possible to obtain a stable spray without any sheath liquid being employed. Selected small peptides were separated with CEC columns (100 microm i.d./25 cm long) packed with 3 microm Hypersil C8 or C18 bonded silica particles with an eluent composed of ammonium acetate/acetonitrile. Peptide mixtures of desmopressin, peptide A, oxytocin, carbetocin and [Met(5)]-enkephalin were detected in the mid-attomole range, which is the lowest amount analyzed using CEC combined with MS detection. It was also observed that sensitivity can be compromised at higher separation voltages. We demonstrate that CEC/nESI-MS, at the current stage of development, represents one of the most sensitive systems for peptide analysis.
Gucek
M
M
TNO Pharma, Division Analysis and Microbiology, Utrechtseweg 48, NL-3700 AJ Zeist, The Netherlands. marjan.gucek@uni-lj.si
Gaspari
M
M
Walhagen
K
K
Vreeken
R J
RJ
Verheij
E R
ER
van der Greef
J
J
D000595:Amino Acid Sequence; D002845:Chromatography / Q000379:methods*; D003894:Deamino Arginine Vasopressin / Q000737:chemistry / Q000302:isolation & purification; D004744:Enkephalin, Methionine / Q000737:chemistry / Q000302:isolation & purification; D013058:Mass Spectrometry / Q000379:methods*; D015688:Oncogene Protein pp60(v-src) / Q000737:chemistry / Q000302:isolation & purification; D010121:Oxytocin / Q000031:analogs & derivatives / Q000737:chemistry / Q000302:isolation & purification; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification; D010455:Peptides / Q000302:isolation & purification*; D011786:Quality Control; D012680:Sensitivity and Specificity
D010446:Peptide Fragments; D010455:Peptides; C098708:peptide A; D010121:Oxytocin; D004744:Enkephalin, Methionine; C020731:carbetocin; D015688:Oncogene Protein pp60(v-src); D003894:Deamino Arginine Vasopressin