Dual-micro-ESI source for precise mass determination on a quadrupole time-of-flight mass spectrometer for genomic and proteomic applications.
A universal dual-electrospray (ESI) source is demonstrated on a quadrupole orthogonal-accelerated time-of-flight mass spectrometer (Q-ToF-MS) for both genomic and proteomic applications. This facile source modification enables internal calibration for consistent mass measurements by a mainstream MS platform and requires no mixing of analyte and calibrant prior to ion formation. In this report, the dual-sprayer is demonstrated in the negative-ion mode for internal calibration of polymerase chain reaction (PCR) amplicons generated from synthetic and genomic templates as well as a proteolytic digest of a naturally phosphorylated protein. For all PCR amplicons, experimentally determined average mass measurements are well within the instrument specifications of better than 0.01%. For the proteolytic fragments of the phosphoprotein, average mass errors of the isotopically resolved peptides are better than 10 ppm.
Flora
Jason W
JW
Department of Chemistry, Virginia Commonwealth University, 1001 West Main Street, Richmond, VA 23284, USA.
Null
Allison P
AP
Muddiman
David C
DC
D000595:Amino Acid Sequence; D002138:Calibration; D002364:Caseins / Q000737:chemistry / Q000378:metabolism; D023281:Genomics / Q000379:methods*; D007477:Ions; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000737:chemistry / Q000378:metabolism; D016133:Polymerase Chain Reaction; D020543:Proteome; D012680:Sensitivity and Specificity; D020539:Sequence Analysis, Protein; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation* / Q000379:methods*; D014357:Trypsin / Q000378:metabolism
D002364:Caseins; D007477:Ions; D010750:Phosphoproteins; D020543:Proteome; D014357:Trypsin