Desorption/ionization of biomolecules from aqueous solutions at atmospheric pressure using an infrared laser at 3 microm.
A new atmospheric pressure (AP) infrared (IR) matrix-assisted laser desorption/ionization (MALDI) ion source was developed and interfaced with a Thermo Finnigan LCQ ion trap mass spectrometer. The source utilized a miniature all-solid-state optical parametric oscillator (OPO)-based IR laser system tunable in the lambda = 1.5-4 microm spectral range and a nitrogen ultraviolet (UV) laser (lambda = 337 nm) for use in comparative studies. The system demonstrated comparable performance at 3 microm and 337 nm wavelengths if UV matrices were used. However, AP IR-MALDI using a 3 microm wavelength showed good performance with a much broader choice of matrices including glycerol and liquid water. AP IR-MALDI mass spectra of peptides in the mass range up to 2000 Da were obtained directly from aqueous solutions at atmospheric conditions for the first time. A potential use of the new AP IR-MALDI ion source includes direct MS analysis of biological cells and tissues in a normal atmospheric environment as well as on-line coupling of mass spectrometers with liquid separation techniques.
Laiko
Victor V
VV
MassTech Inc, Burtonsville, Maryland 20866, USA.
Taranenko
Nelli I
NI
Berkout
Vadym D
VD
Yakshin
Mikhail A
MA
Prasad
Coorg R
CR
Lee
H Sang
HS
Doroshenko
Vladimir M
VM
D000399:Air Pressure; D007259:Infrared Rays; D007834:Lasers; D010455:Peptides / Q000737:chemistry; D012996:Solutions / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D014867:Water / Q000737:chemistry
D010455:Peptides; D012996:Solutions; D014867:Water